SYM53C896 [ETC]
BUS CONTROLLER ; 总线控制器\n
| 型号： | SYM53C896 |
| 厂家： | 
ETC |
| 描述： | BUS CONTROLLER
|
| 文件： | 总360页 (文件大小：3023K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
®
Symbios SYM53C896
PCI to Dual Channel Ultra2
SCSI Multifunction Controller
Technical Manual
January 2000
Version 3.0
®
Order Number S14015.A
This document contains proprietary information of LSI Logic Corporation. The
information contained herein is not to be used by or disclosed to third parties
without the express written permission of an officer of LSI Logic Corporation.
LSI Logic products are not intended for use in life-support appliances, devices,
or systems. Use of any LSI Logic product in such applications without written
consent of the appropriate LSI Logic officer is prohibited.
Document DB14-000083-01, Second Edition (January 2000)
This document describes Version 3.0 of LSI Logic Corporation’s Symbios®
SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller and will
remain the official reference source for all revisions/releases of this product until
rescinded by an update.
To receive product literature, visit us at http://www.lsilogic.com.
LSI Logic Corporation reserves the right to make changes to any products herein
at any time without notice. LSI Logic does not assume any responsibility or
liability arising out of the application or use of any product described herein,
except as expressly agreed to in writing by LSI Logic; nor does the purchase or
use of a product from LSI Logic convey a license under any patent rights,
copyrights, trademark rights, or any other of the intellectual property rights of LSI
Logic or third parties.
Ultra SCSI is the term used by the SCSI Trade Association (STA) to describe
Fast-20 SCSI, as documented in the SCSI-3 Fast-20 Parallel Interface standard,
X3.277-199X.
Ultra2 SCSI is the term used by the SCSI Trade Association (STA) to describe
Fast-40 SCSI, as documented in the SCSI Parallel Interface–2 standard, (SPI–2)
X3T10/1142D.
Copyright © 1997–2000 by LSI Logic Corporation. All rights reserved.
TRADEMARK ACKNOWLEDGMENT
The LSI Logic logo design, Symbios, TolerANT, SCRIPTS, and LVD Link are
registered trademarks or trademarks of LSI Logic Corporation. All other brand
and product names may be trademarks of their respective companies.
ii
Contents
Chapter 1
Introduction
1.1
General Description
1.1.1 New Features in the SYM53C896
1-1
1-3
1-4
1-4
1-5
1-6
1-6
1-7
1-8
1-8
1-8
1-9
1-10
1.2
1.3
1.4
1.5
Benefits of Ultra2 SCSI
Benefits of LVD Link
®
TolerANT Technology
SYM53C896 Benefits Summary
1.5.1
1.5.2
1.5.3
1.5.4
1.5.5
1.5.6
1.5.7
SCSI Performance
PCI Performance
Integration
Ease of Use
Flexibility
Reliability
Testability
Chapter 2
Functional Description
2.1
PCI Functional Description
2-2
2-3
2.1.1
2.1.2
2.1.3
2.1.4
PCI Addressing
PCI Bus Commands and Functions Supported
Internal Arbiter
2-4
2-10
2-10
2-18
2-18
2-19
2-20
2-20
2-21
2-22
2-23
PCI Cache Mode
2.2
SCSI Functional Description
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.2.6
2.2.7
SCRIPTS Processor
Internal SCRIPTS RAM
64-Bit Addressing in SCRIPTS
Hardware Control of SCSI Activity LED
Designing an Ultra2 SCSI System
Prefetching SCRIPTS Instructions
Opcode Fetch Burst Capability
Contents
iii
2.2.8
2.2.9
Load/Store Instructions
2-24
2-24
2-25
2-25
2-28
2-32
2-38
2-39
2-41
2-48
2-51
2-55
2-57
2-57
2-58
2-58
2-59
2-59
2-60
2-60
JTAG Boundary Scan Testing
2.2.10 SCSI Loopback Mode
2.2.11 Parity Options
2.2.12 DMA FIFO
2.2.13 SCSI Bus Interface
2.2.14 Select/Reselect During Selection/Reselection
2.2.15 Synchronous Operation
2.2.16 Interrupt Handling
2.2.17 Interrupt Routing
2.2.18 Chained Block Moves
Parallel ROM Interface
2.3
2.4
Serial EEPROM Interface
2.4.1
2.4.2
Default Download Mode
No Download Mode
2.5
Power Management
2.5.1
2.5.2
2.5.3
2.5.4
Power State D0
Power State D1
Power State D2
Power State D3
Chapter 3
Signal Descriptions
3.1
3.2
Internal Pull-ups on SYM53C896 Signals
PCI Bus Interface Signals
3-4
3-5
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.2.6
3.2.7
3.2.8
System Signals
3-5
Address and Data Signals
Interface Control Signals
Arbitration Signals
3-6
3-7
3-8
Error Reporting Signals
Interrupt Signals
3-9
3-10
3-11
3-12
3-13
3-13
3-16
3-19
3-20
SCSI Function A GPIO Signals
SCSI Function B GPIO Signals
3.3
SCSI Bus Interface Signals
3.3.1
3.3.2
SCSI Function A Signals
SCSI Function B Signals
3.4
3.5
ROM Flash and Memory Interface Signals
Test Interface Signals
iv
Contents
3.6
3.7
Power and Ground Signals
MAD Bus Programming
3-21
3-23
Chapter 4
Chapter 5
Registers
4.1
4.2
4.3
4.4
PCI Configuration Registers
4-1
4-20
SCSI Registers
64-Bit SCRIPTS Selectors
Phase Mismatch Jump Registers
4-106
4-109
SCSI SCRIPTS Instruction Set
5.1
SCSI SCRIPTS
5-1
5-3
5.1.1
Sample Operation
5.2
Block Move Instructions
5-4
5.2.1
5.2.2
5.2.3
First Dword
5-5
Second Dword
Third Dword
5-14
5-14
5-15
5-15
5-22
5-23
5-23
5-24
5-24
5-24
5-27
5-27
5-33
5-33
5-34
5-35
5-35
5-36
5-36
5-37
5-38
5-39
5.3
5.4
I/O Instructions
5.3.1
5.3.2
First Dword
Second Dword
Read/Write Instructions
5.4.1
5.4.2
5.4.3
5.4.4
First Dword
Second Dword
Read-Modify-Write Cycles
Move To/From SFBR Cycles
5.5
5.6
Transfer Control Instructions
5.5.1
5.5.2
5.5.3
First Dword
Second Dword
Third Dword
Memory Move Instructions
5.6.1
5.6.2
5.6.3
5.6.4
First Dword
Read/Write System Memory from a SCRIPTS
Second Dword
Third Dword
5.7
Load/Store Instructions
5.7.1
5.7.2
First Dword
Second Dword
Contents
v
Chapter 6
Specifications
6.1
6.2
6.3
6.4
DC Characteristics
6-1
6-7
TolerANT Technology Electrical Characteristics
AC Characteristics
6-11
6-13
6-15
6-22
6-38
6-58
PCI and External Memory Interface Timing Diagrams
6.4.1
6.4.2
6.4.3
Target Timing
Initiator Timing
External Memory Timing
6.5
SCSI Timing Diagrams
Appendix A
Appendix B
Register Summary
External Memory Interface Diagram Examples
Index
Customer Feedback
Figures
1.1
1.2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.1
5.1
5.2
5.3
5.4
Typical SYM53C896 System Application
Typical SYM53C896 Board Application
SYM53C896 Block Diagram
1-2
1-3
2-2
Parity Checking/Generation
2-28
2-29
2-32
2-36
2-38
2-41
2-50
2-54
3-2
DMA FIFO Sections
SYM53C896 Host Interface SCSI Data Paths
8-Bit HVD Wiring Diagram for Ultra SCSI
Regulated Termination for Ultra2 SCSI
Determining the Synchronous Transfer Rate
Interrupt Routing Hardware Using the SYM53C896
Block Move and Chained Block Move Instructions
SYM53C896 Functional Signal Grouping
SCRIPTS Overview
5-4
Block Move Instruction - First Dword
Block Move Instruction - Second Dword
Block Move Instruction - Third Dword
5-5
5-14
5-14
vi
Contents
5.5
5.6
5.7
5.8
5.9
First 32-Bit Word of the I/O Instruction
Second 32-Bit Word of the I/O Instruction
Read/Write Instruction - First Dword
Read/Write Instruction - Second Dword
Transfer Control Instructions - First Dword
5-15
5-22
5-23
5-24
5-27
5-33
5-33
5-35
5-36
5-36
5-38
5-39
6-2
5.10 Transfer Control Instructions - Second Dword
5.11 Transfer Control Instructions - Third Dword
5.12 Memory Move Instructions - First Dword
5.13 Memory Move Instructions - Second Dword
5.14 Memory Move Instructions - Third Dword
5.15 Load/Store Instruction - First Dword
5.16 Load/Store Instructions - Second Dword
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
LVD Driver
LVD Receiver
6-3
Rise and Fall Time Test Condition
SCSI Input Filtering
6-8
6-8
Hysteresis of SCSI Receivers
Input Current as a Function of Input Voltage
Output Current as a Function of Output Voltage
External Clock
6-9
6-9
6-10
6-11
6-12
6-12
6-15
6-16
6-17
6-18
6-19
6-21
6-23
6-25
6-27
6-29
6-31
6-33
6-35
6-37
6-39
6-42
Reset Input
6.10 Interrupt Output
6.11 PCI Configuration Register Read
6.12 PCI Configuration Register Write
6.13 Operating Registers/SCRIPTS RAM Read, 32-Bit
6.14 Operating Register/SCRIPTS RAM Read, 64-Bit
6.15 Operating Register/SCRIPTS RAM Write, 32-Bit
6.16 Operating Register/SCRIPTS RAM Write, 64-Bit
6.17 Nonburst Opcode Fetch, 32-Bit Address and Data
6.18 Burst Opcode Fetch, 32-Bit Address and Data
6.19 Back-to-Back Read, 32-Bit Address and Data
6.20 Back-to-Back Write, 32-Bit Address and Data
6.21 Burst Read, 32-Bit Address and Data
6.22 Burst Read, 64-Bit Address and Data
6.23 Burst Write, 32-Bit Address and Data
6.24 Burst Write, 64-Bit Address and Data
6.25 External Memory Read
6.26 External Memory Write
Contents
vii
6.27 Normal/Fast Memory (≥ 128 Kbytes) Single Byte
Access Read Cycle
6-44
6-46
6-48
6.28 Normal/Fast Memory (≥ 128 Kbytes) Single Byte
Access Write Cycle
6.29 Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte
Access Read Cycle
6.30 Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte
Access Write Cycle
6-50
6-52
6-54
6-56
6-57
6-58
6-58
6-59
6-59
6-63
6-66
6-67
B-1
6.31 Slow Memory (≥ 128 Kbytes) Read Cycle
6.32 Slow Memory (≥ 128 Kbytes) Write Cycle
6.33 ≤ 64 Kbytes ROM Read Cycle
6.34 ≤ 64 Kbytes ROM Write Cycle
6.35 Initiator Asynchronous Send
6.36 Initiator Asynchronous Receive
6.37 Target Asynchronous Send
6.38 Target Asynchronous Receive
6.39 Initiator and Target Synchronous Transfer
6.40 SYM53C896 329 BGA (Bottom View)
6.41 SYM53C896 329 BGA Mechanical Drawing
B.1
B.2
B.3
16 Kbyte Interface with 200 ns Memory
64 Kbyte Interface with 150 ns Memory
128, 256, 512 Kbyte or 1 Mbyte Interface with
150 ns Memory
B-2
B-3
B-4
B.4
512 Kbyte Interface with 150 ns Memory
Tables
2.1
PCI Bus Commands and Encoding Types for the
SYM53C896
2-4
2-13
2-26
2-27
2-27
2-34
2-56
2-58
2-59
3-4
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.1
3.2
PCI Cache Mode Alignment
Bits Used for Parity Control and Generation
SCSI Parity Control
SCSI Parity Errors and Interrupts
HVD Signals
Parallel ROM Support
Mode A Serial EEPROM Data Format
Power States
SYM53C896 Internal Pull-ups and Pull-downs
System Signals
3-5
viii
Contents
3.3
3.4
3.5
3.6
3.7
3.8
3.9
Address and Data Signals
Interface Control Signals
Arbitration Signals
3-6
3-7
3-8
Error Reporting Signals
Interrupt Signals
3-9
3-10
3-11
3-12
3-13
3-14
3-15
3-16
3-18
3-19
3-20
3-21
3-24
4-2
SCSI Function A GPIO Signals
SCSI Function B GPIO Signals
3.10 SCSI Bus Interface Signals
3.11 SCSI Function A Signals
3.12 SCSI Function A_SCTRL Signals
3.13 SCSI Function B Signals
3.14 SCSI Function B_SCRTL Signals
3.15 ROM Flash and Memory Interface Signals
3.16 Test Interface Signals
3.17 Power and Ground Signals
3.18 Decode of MAD[3:1] Pins
4.1
4.2
4.3
PCI Configuration Register Map
SCSI Register Map
4-21
Examples of Synchronous Transfer Periods and Rates for
SCSI-1
4-35
4.4
Example Transfer Periods and Rates for Fast SCSI-2,
Ultra and Ultra2
4-35
4-37
4-48
5-25
6-1
4.5
4.6
5.1
6.1
6.2
6.3
Maximum Synchronous Offset
SCSI Synchronous Data FIFO Word Count
Read/Write Instructions
Absolute Maximum Stress Ratings
Operating Conditions
6-2
LVD Driver SCSI Signals—SD[15:0], SDP[1:0], SREQ/,
SREQ2/, SACK/, SACK2/, SMSG/, SIO/, SCD/, SATN/,
SBSY/, SSEL/, SRST/
6-2
6.4
LVD Receiver SCSI Signals—SD[15:0], SDP[1:0], SREQ/,
SREQ2/, SACK/, SACK2/, SMSG/, SIO/, SCD/, SATN/,
SBSY/, SSEL/, SRST/
6-3
6-3
6-3
6.5
6.6
6.7
A and B DIFFSENS SCSI Signals
Input Capacitance
Bidirectional Signals—GPIO0_FETCH/, GPIO1_MASTER/,
1
6-4
GPIO2, GPIO3, GPIO4, MAD[7:0]
1
6.8
Output Signals—MAS/[1:0], MCE/, MOE/_TESTOUT ,
Contents
ix
MWE/, TDO
6-4
6.9
Bidirectional Signals—AD[63:0], C_BE[7:0]/, FRAME/,
IRDY/, TRDY/, DEVSEL/, STOP/, PERR/, PAR, PAR64,
REQ64/, ACK64/
6-5
6-5
6.10 Input Signals—CLK, GNT/, IDSEL, INT_DIR, RST/, SCLK,
TCK, TDI, TEST_HSC, TEST_RST/, TMS
6.11 Output Signals—INTA, INTB, ALT_INTA, ALT_INTB,
REQ/
6-6
6-6
6.12 Output Signal—SERR/
6.13 TolerANT Technology Electrical Characteristics for SE
SCSI Signals
6-7
6-11
6-12
6-12
6-15
6-16
6-17
6-18
6-19
6-20
6-22
6-24
6-26
6-28
6-30
6-32
6-34
6-36
6-38
6-41
6.14 External Clock
6.15 Reset Input
6.16 Interrupt Output
6.17 PCI Configuration Register Read
6.18 PCI Configuration Register Write
6.19 Operating Register/SCRIPTS RAM Read, 32-Bit
6.20 Operating Register/SCRIPTS RAM Read, 64-Bit
6.21 Operating Register/SCRIPTS RAM Write, 32-Bit
6.22 Operating Register/SCRIPTS RAM Write, 64-Bit
6.23 Nonburst Opcode Fetch, 32-Bit Address and Data
6.24 Burst Opcode Fetch, 32-Bit Address and Data
6.25 Back-to-Back Read, 32-Bit Address and Data
6.26 Back-to-Back Write, 32-Bit Address and Data
6.27 Burst Read, 32-Bit Address and Data
6.28 Burst Read, 64-Bit Address and Data
6.29 Burst Write, 32-Bit Address and Data
6.30 Burst Write, 64-Bit Address and Data
6.31 External Memory Read
6.32 External Memory Write
6.33 Normal/Fast Memory (≥ 128 Kbytes) Single Byte
Access Read Cycle
6-44
6.34 Normal/Fast Memory (≥ 128 Kbytes) Single Byte
Access Write Cycle
6-46
6-52
6-54
6-56
6-57
6.35 Slow Memory (≥ 128 Kbytes) Read Cycle
6.36 Slow Memory (≥ 128 Kbytes) Write Cycle
6.37 ≤ 64 Kbytes ROM Read Cycle
6.38 ≤ 64 Kbytes ROM Write Cycle
x
Contents
6.39 Initiator Asynchronous Send
6-58
6-58
6-59
6-59
6-60
6-60
6.40 Initiator Asynchronous Receive
6.41 Target Asynchronous Send
6.42 Target Asynchronous Receive
6.43 SCSI-1 Transfers (SE 5.0 Mbytes)
6.44 SCSI-1 Transfers (Differential 4.17 Mbytes)
6.45 SCSI-2 Fast Transfers 10.0 Mbytes (8-bit transfers) or
20.0 Mbytes (16-bit transfers) 40 MHz Clock
6.46 SCSI-2 Fast Transfers 10.0 Mbytes (8-bit transfers) or
20.0 Mbytes (16-bit transfers) 50 MHz Clock
6.47 Ultra SCSI SE Transfers 20.0 Mbytes (8-bit transfers) or
40.0 Mbytes (16-bit transfers) Quadrupled 40 MHz Clock
6.48 Ultra SCSI HVD Transfers 20.0 Mbytes (8-bit transfers)
or 40.0 Mbytes (16-bit transfers) 80 MHz Clock
6.49 Ultra2 SCSI Transfers 40.0 Mbyte (8-bit transfers) or
80.0 Mbyte (16-bit transfers) Quadrupled 40 MHz Clock
6.50 Signal Names and BGA Position
6-61
6-61
6-62
6-62
6-63
6-64
6-65
A-1
6.51 Signal Names By BGA Position
A.1
SYM53C896 Register Map
Contents
xi
xii
Contents
Preface
This book is the primary reference and technical manual for LSI Logic
®
Corporation’s Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI
Multifunction Controller. It contains a complete functional description for
the product and includes complete physical and electrical specifications.
Audience
This document was prepared for system designers and programmers
who are using this device to design an Ultra2 SCSI port for PCI-based
personal computers, workstations, servers or embedded applications.
Organization
This document has the following chapters and appendixes:
•
•
Chapter 1, Introduction, describes the general information about the
SYM53C896.
Chapter 2, Functional Description, describes the main functional
areas of the chip in more detail, including the interfaces to the SCSI
bus and external memory.
•
•
•
•
•
Chapter 3, Signal Descriptions, contains the pin diagram and signal
descriptions.
Chapter 4, Registers, describes each bit in the operating registers,
and is organized by register address.
Chapter 5, SCSI SCRIPTS Instruction Set, defines all of the SCSI
SCRIPTS instructions that are supported by the SYM53C896.
Chapter 6, Specifications, contains the electrical characteristics and
AC timing diagrams.
Appendix A, Register Summary, is a register summary.
Preface
xiii
•
Appendix B, External Memory Interface Diagram Examples,
contains several example interface drawings for connecting the
SYM53C896 to external ROMs.
Related Publications
For background please contact:
ANSI
11 West 42nd Street
New York, NY 10036
(212) 642-4900
Ask for document number X3.131-199X (SCSI-2)
Global Engineering Documents
15 Inverness Way East
Englewood, CO 80112
(800) 854-7179 or (303) 397-7956 (outside U.S.) FAX (303) 397-2740
Ask for document number X3.131-1994 (SCSI-2) or X3.253
(SCSI-3 Parallel Interface)
ENDL Publications
14426 Black Walnut Court
Saratoga, CA 95070
(408) 867-6642
Document names: SCSI Bench Reference, SCSI Encyclopedia,
SCSI Tutor
Prentice Hall
113 Sylvan Avenue
Englewood Cliffs, NJ 07632
(800) 947-7700
Ask for document number ISBN 0-13-796855-8, SCSI: Understanding
the Small Computer System Interface
LSI Logic (Storage Components) Electronic Bulletin Board
(719) 533-7235
®
Ask for document Symbios PCI to SCSI I/O Processors Programming
Guide, Order Number J25972I
xiv
Preface
SCSI Electronic Bulletin Board
(719) 533-7950
LSI Logic World Wide Web Home Page
www.lsil.com
LSI Logic Internet Anonymous FTP Site
ftp.symbios.com (204.131.200.1)
Directory: /pub/symchips/scsi
PCI Special Interest Group
2575 N. E. Katherine
Hillsboro, OR 97214
(800) 433-5177; (503) 693-6232 (International); FAX (503) 693-8344
Conventions Used in This Manual
The word assert means to drive a signal true or active. The word
deassert means to drive a signal false or inactive.
Hexadecimal numbers are indicated by the prefix “0x” —for example,
0x32CF. Binary numbers are indicated by the prefix “0b” —for example,
0b0011.0010.1100.1111.
Revision Record
Revision
Date
Remarks
0.5
7/97
Advanced Information Data - contains Signal Descriptions, Registers, and
Mechanical Drawings.
0.6
10/22/97
First Draft - Added: Introduction, Functional Description, SCSI SCRIPTS
Instruction Set, Electrical Characteristics, Register Summary, and External
Memory Interface Diagram Examples.
1.0
2.0
3/11/98
1/18/99
Changes throughout to reflect manual review process and preproduction
chip revisions.
Miscellaneous changes/corrections to reflect product qualification. A table
showing SYM53C896 internal pull-up and pull-downs has been added to
Chapter 3.
Preface
xv
Revision
Date
Remarks
2.1
3.0
4/12/99
11/99
Miscellaneous cosmetic/format changes from Symbios to LSI Logic.
Final version.
xvi
Preface
Chapter 1
Introduction
This chapter provides a general overview of the SYM53C896 PCI to Dual
Channel Ultra2 SCSI Multifunction Controller. The chapter contains the
following sections:
•
•
•
•
•
Section 1.1, “General Description”
Section 1.2, “Benefits of Ultra2 SCSI”
Section 1.3, “Benefits of LVD Link”
®
Section 1.4, “TolerANT Technology”
Section 1.5, “SYM53C896 Benefits Summary”
1.1 General Description
The SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction
Controller brings Ultra2 SCSI performance to host adapter, workstation,
and general computer designs, making it easy to add a high-performance
SCSI bus to any PCI system. It supports Ultra2 SCSI transfer rates and
allows increased SCSI connectivity and cable length with Low Voltage
Differential (LVD) signaling for SCSI devices.
The SYM53C896 has a local memory bus for local storage of the
device’s BIOS ROM in flash memory or standard EPROMs. The
SYM53C896 supports programming of local flash memory for updates to
BIOS. The chip is packaged in a 329 Ball Grid Array (BGA) package.
System diagrams showing the connections of the SYM53C896 with an
external ROM or flash memory are shown in Appendix B, “External
Memory Interface Diagram Examples”.
LVD Link™ technology is the LSI Logic implementation of LVD. LVD Link
transceivers allow the SYM53C896 to perform either Single-Ended (SE)
or LVD transfers, and support external High Voltage Differential (HVD)
transceivers. The SYM53C896 integrates a high-performance SCSI core,
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
1-1
a 64-bit PCI bus master DMA core, and the LSI Logic SCSI SCRIPTS™
processor to meet the flexibility requirements of SCSI-3 and Ultra2 SCSI
standards. It is designed to implement multithreaded I/O algorithms with
a minimum of processor intervention, solving the protocol overhead
problems of previous intelligent and nonintelligent adapter designs.
Figure 1.1 illustrates a typical SYM53C896 system and Figure 1.2
illustrates a typical SYM53C896 board application.
Figure 1.1 Typical SYM53C896 System Application
Fixed Disk, Optical Disk,
Printer, Tape, and Other
Peripherals
SCSI Bus
SCSI Bus
SYM53C896 PCI
to Wide Ultra2 SCSI
Function A
PCI Bus
Interface
Controller
and
SYM53C896 PCI
to Wide Ultra2 SCSI
Function B
Fixed Disk, Optical Disk,
Printer, Tape, and Other
Peripherals
PCI Graphic Accelerator
PCI Fast Ethernet
Memory
Controller
Central
Processing
Unit
Memory
(CPU)
Typical PCI Computer
System Architecture
1-2
Introduction
Figure 1.2 Typical SYM53C896 Board Application
SCSI Data,
Parity, and
Control Signals
Memory Control
Block
Function A
68 Pin
Wide SCSI
Connector
Memory
Address/Data
Bus
Flash EEPROM
SYM53C896
64 Bit PCI
Serial EEPROM
Function A
A_GPIO/[1:0]
B_GPIO/[1:0]
to
SCSI Data,
Parity, and
Control Signals
Dual Channel SCSI
Controller
Function B
68 Pin
Serial EEPROM
Function B
Wide SCSI
Connector
PCI Interface
PCI Address, Data, Parity and Control Signals
1.1.1 New Features in the SYM53C896
The SYM53C896 is functionally similar to the SYM53C876 PCI to Dual
Channel SCSI Multifunction Controller, with added support for Ultra2
SCSI. Some software enhancements, and the use of LVD, are needed to
enable the chip to transfer data at Ultra2 SCSI transfer rates.
•
•
64-bit PCI Interface.
Able to handle SCSI phase mismatches in SCRIPTS without
interrupting the CPU.
•
•
•
•
•
Two wide Ultra2 SCSI channels in a single package.
Separate 8 Kbyte internal SCRIPTS RAMs.
JTAG boundary scanning.
RAID ready alternative interrupt signaling.
PC99 Power Management - including automatic download of
Subsystem Vendor ID and Subsystem ID, and PCI power
management levels D0, D1, D2, and D3.
General Description
1-3
•
•
Improved PCI Caching design - improves PCI bus efficiency.
Load/Store data transferred to or from SCRIPTS RAM internal to
chip.
•
•
Hardware control of SCSI activity LED.
Optional 944 byte DMA FIFO supports large block transfers at Ultra2
SCSI speeds. The default FIFO size of 112 bytes is also supported.
•
32-bit ISTAT registers (Interrupt Status Zero (ISTAT0), Interrupt Status
One (ISTAT1), Mailbox Zero (MBOX0), Mailbox One (MBOX1)).
1.2 Benefits of Ultra2 SCSI
Ultra2 SCSI is an extension of the SPI-2 draft standard that allows faster
synchronous SCSI transfer rates and defines a new physical layer, LVD
SCSI, that provides an incremental evolution from SCSI-2 and Ultra
SCSI. When enabled, Ultra2 SCSI performs 40 mega transfers per
second, which results in approximately double the synchronous transfer
rates of Ultra SCSI. The SYM53C896 can perform 16-bit, Ultra2 SCSI
synchronous transfers as fast as 80 Mbytes/s on each channel for a total
bandwidth of 160 Mbytes/s. This advantage is most noticeable in heavily
loaded systems, or large block size applications such as video
on-demand and image processing.
An advantage of Ultra2 SCSI is that it significantly improves SCSI
bandwidth while preserving existing hardware and software investments.
The primary software changes required are to enable the chip to perform
synchronous negotiations for Ultra2 SCSI rates, and to enable the clock
quadrupler. Ultra2 SCSI uses the same connectors as Ultra SCSI, but
can operate with longer cables and more devices on the bus. Chapter 2,
“Functional Description” contains more information on migrating an Ultra
SCSI design to an Ultra2 SCSI design.
1.3 Benefits of LVD Link
The SYM53C896 supports LVD for SCSI, a signaling technology that
increases the reliability of SCSI data transfers over longer distances than
are supported by SE SCSI. The low current output of LVD allows the I/O
transceivers to be integrated directly onto the chip. LVD provides the
1-4
Introduction
reliability of HVD SCSI without the added cost of external differential
transceivers. Ultra2 SCSI with LVD allows a longer SCSI cable and more
devices on the bus, with the same cables defined in the SCSI-3 Parallel
Interface standard for Fast-20 (Ultra SCSI). LVD provides a long-term
migration path to even faster SCSI transfer rates without compromising
signal integrity, cable length, or connectivity.
For backward compatibility to existing SE devices, the SYM53C896
features universal LVD Link transceivers that can support LVD SCSI, SE,
and HVD modes. The LVD Link technology also supports HVD signaling
in legacy systems, when external transceivers are connected to the
SYM53C896. This allows the SYM53C896 to be used in both legacy and
Ultra2 SCSI applications.
1.4 TolerANT® Technology
The SYM53C896 features TolerANT technology, which includes active
negation on the SCSI drivers and input signal filtering on the SCSI
receivers. Active negation causes the SCSI Request, Acknowledge,
Data, and Parity signals to be actively driven high rather than passively
pulled up by terminators. Active negation is enabled by setting bit 7 in
the SCSI Test Three (STEST3) register.
TolerANT receiver technology improves data integrity in unreliable
cabling environments, where other devices would be subject to data
corruption. TolerANT receivers filter the SCSI bus signals to eliminate
unwanted transitions, without the long signal delay associated with
RC-type input filters. This improved driver and receiver technology helps
eliminate double clocking of data, the single biggest reliability issue with
SCSI operations. TolerANT input signal filtering is a built-in feature of the
SYM53C896 and all LSI Logic fast SCSI, Ultra SCSI, and Ultra2 SCSI
devices.
The benefits of TolerANT technology include increased immunity to noise
when the signal is going high, better performance due to balanced duty
cycles, and improved fast SCSI transfer rates. In addition, TolerANT SCSI
devices do not cause glitches on the SCSI bus at power-up or
power-down, so other devices on the bus are also protected from data
corruption. When it is used with the LVD Link transceivers, TolerANT
technology provides excellent signal quality and data reliability in real
TolerANT® Technology
1-5
world cabling environments. TolerANT technology is compatible with both
the Alternative One and Alternative Two termination schemes proposed
by the American National Standards Institute.
1.5 SYM53C896 Benefits Summary
This section provides an overview of the SYM53C896 features and
benefits. It contains information on SCSI Performance, PCI Performance,
Integration, Ease of Use, Flexibility, Reliability, and Testability.
1.5.1 SCSI Performance
•
Has integrated LVD Link universal transceivers which:
–
–
–
Support SE, LVD, and HVD signals (with external transceivers).
Allow greater device connectivity and longer cable length.
LVD Link transceivers save the cost of external differential
transceivers.
–
Supports a long-term performance migration path.
•
With a 944 byte FIFO, the chip can efficiently burst up to 512 bytes
across the PCI bus.
•
•
Two separate SCSI channels on one chip.
Performs wide, Ultra2 SCSI synchronous transfers as fast as
80 Mbytes/s on each SCSI channel for a total of 160 Mbytes/s.
•
•
•
Can handle phase mismatches in SCRIPTS without interrupting the
system processor.
On-chip SCSI clock quadrupler allows the chip to achieve Ultra2
SCSI transfer rates with an input frequency of 40 MHz.
Includes 8 Kbytes of internal RAM for SCRIPTS instruction storage
for each SCSI channel.
•
•
•
31 levels of SCSI synchronous offset.
Supports variable block size and scatter/gather data transfers.
Performs sustained memory-to-memory DMA transfers to
approximately 100 Mbytes/s.
•
Minimizes SCSI I/O start latency.
1-6
Introduction
•
•
•
Performs complex bus sequences without interrupts, including
restoring data pointers.
Reduces ISR overhead through a unique interrupt status reporting
method.
Load/Store SCRIPTS instructions increase performance of data
transfers to and from the chip registers without using PCI cycles.
•
•
SCRIPTS support of 64-bit addressing.
Supports target disconnect and later reconnect with no interrupt to
the system processor.
•
•
Supports multithreaded I/O algorithms in SCSI SCRIPTS with fast
I/O context switching.
Expanded Register Move instruction supports additional arithmetic
capability.
1.5.2 PCI Performance
•
•
Complies with the PCI 2.1 specification.
64-bit or 32-bit 33 MHz PCI interface.
–
–
Dual Address Cycle (DAC) can be generated for all SCRIPTS.
True PCI Multifunction Device - presents one electrical load to
the PCI Bus.
•
Bursts 2/4, 4/8, 8/16, 16/32, 32/64, or 64/128 qword/dword transfers
across the PCI bus.
•
•
•
•
Supports 64-bit or 32-bit word data bursts with variable burst lengths.
Prefetches up to 8 dwords of SCRIPTS instructions.
Bursts SCRIPTS opcode fetches across the PCI bus.
Performs zero wait-state bus master data bursts up to 264 Mbytes/s
(@ 33 MHz).
•
•
Supports PCI Cache Line Size register.
Supports PCI Write and Invalidate, Read Line, and Read Multiple
commands.
•
Complies with PCI Bus Power Management Specification Rev 1.1.
SYM53C896 Benefits Summary
1-7
1.5.3 Integration
•
•
•
•
Dual channel Ultra2 SCSI PCI Multifunction controller.
Integrated LVD transceivers.
Full 64-bit or 32-bit PCI DMA bus master.
Can be used as a third-party PCI bus DMA controller by using
Memory-to-Memory Move instructions.
•
Integrated SCRIPTS processor.
1.5.4 Ease of Use
•
Up to one megabyte of add-in memory support for BIOS and
SCRIPTS storage.
•
•
•
Direct PCI to SCSI connection.
Reduced SCSI development effort.
Compiler-compatible with existing SYM53C7XX and SYM53C8XX
family SCRIPTS.
•
Direct connection to PCI and SCSI SE, LVD and HVD (needs
external transceivers).
•
•
•
Development tools and sample SCSI SCRIPTS available.
Maskable and pollable interrupts.
Wide SCSI, A or P cable, and up to 15 devices per SCSI channel
supported.
•
Three programmable SCSI timers: Select/Reselect,
Handshake-to-Handshake, and General Purpose. The time-out
period is programmable from 100 µs to greater than 25.6 seconds.
•
•
•
Software for PC-based operating system support.
Support for relative jumps.
SCSI Selected As ID bits for responding with multiple IDs.
1.5.5 Flexibility
•
Universal LVD transceivers are backward compatible with SE or HVD
devices.
•
High level programming interface (SCSI SCRIPTS).
1-8
Introduction
•
•
•
Programs local and bus flash memory.
Selectable 112 or 944 byte DMA FIFO for backward compatibility.
Tailored SCSI sequences execute from main system RAM or internal
SCRIPTS RAM.
•
Flexible programming interface to tune I/O performance or to adapt
to unique SCSI devices.
•
•
•
•
•
Support for changes in the logical I/O interface definition.
Low level access to all registers and all SCSI bus signals.
Fetch, Master, and Memory Access control pins.
Separate SCSI and system clocks.
SCSI clock quadrupler bits enable Ultra2 SCSI transfer rates with a
40 MHz SCSI clock input.
•
•
•
Selectable IRQ pin disable bit.
Ability to route system clock to SCSI clock.
Compatible with 3.3 V and 5 V PCI.
1.5.6 Reliability
•
•
•
2 kV ESD protection on SCSI signals.
Protection against bus reflections due to impedance mismatches.
Controlled bus assertion times (reduces RFI, improves reliability, and
eases FCC certification).
•
•
Latch-up protection greater than 150 mA.
Voltage feed-through protection (minimum leakage current through
SCSI pads).
•
•
•
More than 25% of pins are power and ground.
Power and ground isolation of I/O pads and internal chip logic.
TolerANT technology provides:
–
Active negation of SCSI Data, Parity, Request, and Acknowledge
signals for improved fast SCSI transfer rates.
–
Input signal filtering on SCSI receivers improves data integrity,
even in noisy cabling environments.
SYM53C896 Benefits Summary
1-9
1.5.7 Testability
•
•
•
•
•
All SCSI signals accessible through programmed I/O.
SCSI loopback diagnostics.
SCSI bus signal continuity checking.
Support for single step mode operation.
JTAG boundary scan.
1-10
Introduction
Chapter 2
Functional Description
Chapter 2 is divided into the following sections:
•
•
•
•
•
Section 2.1, “PCI Functional Description”
Section 2.2, “SCSI Functional Description”
Section 2.3, “Parallel ROM Interface”
Section 2.4, “Serial EEPROM Interface”
Section 2.5, “Power Management”
The SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction
Controller is composed of the following modules:
•
•
•
•
64-bit PCI Interface.
Two independent PCI-to-Wide Ultra2 SCSI Controllers.
ROM/Flash Memory Controller.
Serial EEPROM Controller.
Figure 2.1 illustrates the relationship between these modules.
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
2-1
Figure 2.1 SYM53C896 Block Diagram
PCI Bus
64-Bit PCI Interface, PCI Configuration Registers (2 sets)
Wide Ultra2 SCSI Controller
Wide Ultra2 SCSI Controller
8 Dword SCRIPTS
Prefetch Buffer
8 Dword SCRIPTS
Prefetch Buffer
8 Kbyte
SCRIPTS RAM
8 Kbyte
SCRIPTS RAM
Local
Memory
Bus
SCSI FIFO and SCSI Control Block
SCSI FIFO and SCSI Control Block
Universal TolerANT
Drivers and Receivers
Universal TolerANT
Drivers and Receivers
JTAG
SCSI Function A
Wide Ultra2
SCSI Bus
ROM/Flash 2-Wire Serial 2-Wire Serial SCSI Function B
Memory EEPROM Bus EEPROM Bus Wide Ultra2
Bus
(Function A) (Function B)
SCSI Bus
2.1 PCI Functional Description
The SYM53C896 implements two PCI-to-Wide Ultra2 SCSI controllers in
a single package. This configuration presents only one load to the PCI
bus and uses one REQ/ - GNT/ pair to arbitrate for PCI bus mastership.
However, separate interrupt signals are generated for SCSI Function A
and SCSI Function B.
2-2
Functional Description
2.1.1 PCI Addressing
There are three physical PCI-defined address spaces:
•
•
•
PCI Configuration Space.
I/O Space for operating registers.
Memory Space for operating registers.
2.1.1.1 Configuration Space
The host processor uses this configuration space to initialize the
SYM53C896. Two independent sets of configuration space registers are
defined, one set for each SCSI function. The Configuration registers are
accessible only by system BIOS during PCI configuration cycles. Each
configuration space is a contiguous 256 X 8-bit set of addresses.
Decoding C_BE[3:0]/ determines if a PCI cycle is intended to access the
configuration register space. The IDSEL bus signal is a “chip select” that
allows access to the configuration register space only. A configuration
read/write cycle without IDSEL is ignored. The eight lower order address
bits (AD[7:0]) are used to select a specific 8-bit register. Since the
SYM53C896 is a PCI multifunction device, bits AD[10:8] decode either
SCSI Function A Configuration register (AD[10:8] = 0b000) or SCSI
Function B Configuration register (AD[10:8] = 0b001).
At initialization time, each PCI device is assigned a base address (in the
case of the SYM53C896, the upper 24 bits of the address are selected)
for memory accesses and I/O accesses. On every access, the
SYM53C896 compares its assigned base addresses with the value on
the Address/Data bus during the PCI address phase. If there is a match
of the upper 24 bits, the access is for the SYM53C896 and the low-order
eight bits define the register to be accessed. A decode of C_BE[3:0]/
determines which registers and what type of access is to be performed.
I/O Space – The PCI specification defines I/O space as a contiguous
32-bit I/O address that is shared by all system resources, including the
SYM53C896. Base Address Register Zero determines which 256-byte
I/O area this device occupies.
Memory Space – The PCI specification defines memory space as a
contiguous 64-bit memory address that is shared by all system
resources, including the SYM53C896. Base Address Register One
determines which 1 Kbyte memory area this device occupies. Each SCSI
function uses a 8 Kbyte SCRIPTS RAM memory space. Base Address
PCI Functional Description
2-3
Register Two determines the 8 Kbyte memory area the SCRIPTS RAM
occupies.
2.1.2 PCI Bus Commands and Functions Supported
Bus commands indicate to the target the type of transaction the master
is requesting. Bus commands are encoded on the C_BE[3:0]/ lines
during the address phase. PCI bus commands and encoding types
appear in Table 2.1.
Table 2.1
PCI Bus Commands and Encoding Types for the SYM53C896
C_BE[3:0]/ Command Type
Supported as Master Supported as Slave
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Interrupt Acknowledge
Special Cycle
I/O Read
No
No
No
No
Yes
Yes
N/A
N/A
Yes
Yes
N/A
N/A
No
Yes
I/O Write
Yes
Reserved
N/A
Reserved
N/A
Memory Read
Memory Write
Reserved
Yes
Yes
N/A
Reserved
N/A
Configuration Read
Configuration Write
Memory Read Multiple
DAC
Yes
No
Yes
Yes1
Yes
Yes1
Yes (defaults to 0110)
Yes
Memory Read Line
Yes (defaults to 0110)
Yes (defaults to 0111)
Memory Write and Invalidate Yes2
1. See the DMA Mode (DMODE) register.
2. See the Chip Test Three (CTEST3) register.
2-4
Functional Description
2.1.2.1 Interrupt Acknowledge Command
The SYM53C896 does not respond to this command as a slave and it
never generates this command as a master.
2.1.2.2 Special Cycle Command
The SYM53C896 does not respond to this command as a slave and it
never generates this command as a master.
2.1.2.3 I/O Read Command
The I/O Read command reads data from an agent mapped in the I/O
address space. All 64 address bits are decoded.
2.1.2.4 I/O Write Command
The I/O Write command writes data to an agent mapped in the I/O
address space. All 64 address bits are decoded.
2.1.2.5 Reserved Command
The SYM53C896 does not respond to this command as a slave and it
never generates this command as a master.
2.1.2.6 Memory Read Command
The Memory Read command reads data from an agent mapped in the
Memory Address Space. The target is free to do an anticipatory read for
this command only if it can guarantee that such a read has no side
effects.
2.1.2.7 Memory Write Command
The Memory Write command writes data to an agent mapped in the
Memory Address Space. When the target returns “ready”, it assumes
responsibility for the coherency (which includes ordering) of the subject
data.
2.1.2.8 Configuration Read Command
The Configuration Read command reads the configuration space of each
agent. An agent is selected during a configuration access when its
PCI Functional Description
2-5
IDSEL signal is asserted and AD[1:0] are 0b00. During the address
phase of a configuration cycle AD[7:2] addresses one of the 64 dword
registers (where byte enables address the bytes within each dword) in
the configuration space of each device. AD[63:11] are logical don’t cares
to the selected agent. AD[10:8] indicate which device of a multifunction
agent is being addressed.
2.1.2.9 Configuration Write Command
The Configuration Write command transfers data to the configuration
space of each agent. An agent is selected when its IDSEL signal is
asserted and AD[1:0] are 0b00. During the address phase of a
configuration cycle, the AD[7:2] lines address the 64 dword registers
(where byte enables address the bytes within each dword) in the
configuration space of each device. AD[63:11] are logical don’t cares to
the selected agent. AD[10:8] indicate which device of a multifunction
agent is addressed.
2.1.2.10 Memory Read Multiple Command
This command is identical to the Memory Read command except that it
additionally indicates that the master may intend to fetch more than one
cache line before disconnecting. The SYM53C896 supports PCI Memory
Read Multiple functionality and issues Memory Read Multiple commands
on the PCI bus when the Read Multiple mode is enabled. This mode is
enabled by setting bit 2 (ERMP) of the DMA Mode (DMODE) register. If
cache mode is enabled, a Memory Read Multiple command is issued on
all read cycles, except opcode fetches, when the following conditions are
met:
•
•
•
The CLSE bit (Cache Line Size Enable, bit 7, DMA Control (DCNTL)
register) and the ERMP bit (Enable Read Multiple, bit 2, DMA Mode
(DMODE) register) are set.
The Cache Line Size register for each function contains a legal burst
size value (2, 4, 8, 16, 32, or 64) and that value is less than or equal
to the DMODE burst size.
The transfer will cross a cache line boundary.
When these conditions are met, the chip issues a Memory Read Multiple
command instead of a Memory Read during all PCI read cycles.
2-6
Functional Description
Burst Size Selection – The Read Multiple command reads in multiple
cache lines of data in a single bus ownership. The number of cache lines
to read is a multiple of the cache line size specified in Revision 2.1 of
the PCI specification. The logic selects the largest multiple of the cache
line size based on the amount of data to transfer, with the maximum
allowable burst size determined from the DMA Mode (DMODE) burst size
bits, and the Chip Test Five (CTEST5), bit 2.
2.1.2.11 DAC Command
The SYM53C896 performs DACs when 64-bit addressing is required.
See PCI specification 2.1. If any of the selector registers contain a
nonzero value, a DAC will be generated.
2.1.2.12 Memory Read Line Command
This command is identical to the Memory Read command, except that it
additionally indicates that the master intends to fetch a complete cache
line. This command is intended for use with bulk sequential data transfers
where the memory system and the requesting master might gain some
performance advantage by reading to a cache line boundary rather than
a single memory cycle. The Read Line function in the SYM53C896 takes
advantage of the PCI 2.1 specification regarding issuing of this
command.
If the cache mode is disabled, Read Line commands will not be issued.
If the cache mode is enabled, a Read Line command is issued on all
read cycles, except nonprefetch opcode fetches, when the following
conditions are met:
•
•
•
The CLSE (Cache Line Size Enable, bit 7, of the DMA Control
(DCNTL) register) and ERL (Enable Read Line, bit 3, of the DMA
Mode (DMODE) register) bits are set.
The Cache Line Size register for each function must contain a legal
burst size value in dwords (2, 4, 8, 16, 32, 64, or 128) and that value
is less than or equal to the DMODE burst size.
The transfer will cross a dword boundary but not a cache line
boundary.
PCI Functional Description
2-7
When these conditions are met, the chip issues a Read Line command
instead of a Memory Read during all PCI read cycles. Otherwise, it
issues a normal Memory Read command.
Read Multiple with Read Line Enabled – When both the Read
Multiple and Read Line modes are enabled, the Read Line command is
not issued if the above conditions are met. Instead, a Read Multiple
command is issued, even though the conditions for Read Line are met.
If the Read Multiple mode is enabled and the Read Line mode is
disabled, Read Multiple commands are issued if the Read Multiple
conditions are met.
2.1.2.13 Memory Write and Invalidate Command
The Memory Write and Invalidate command is identical to the Memory
Write command, except that it additionally guarantees a minimum
transfer of one complete cache line. That is, the master intends to write
all bytes within the addressed cache line in a single PCI transaction
unless interrupted by the target. This command requires implementation
of the PCI Cache Line Size register at address 0x0C in PCI configuration
space. The SYM53C896 enables Memory Write and Invalidate cycles
when bit 0 (WRIE) in the Chip Test Three (CTEST3) register and bit 4
(WIE) in the PCI Command register are set. When the following
conditions are met, Memory Write and Invalidate commands are issued:
1. The CLSE bit (Cache Line Size Enable, bit 7, of the DMA Control
(DCNTL) register), WRIE bit (Write and Invalidate Enable, bit 0, of the
Chip Test Three (CTEST3) register), and PCI configuration Command
register, bit 4 are set.
2. The Cache Line Size register for each function contains a legal burst
size value in dwords (2, 4, 8, 16, 32, 64, or 128) and that value is
less than or equal to the DMA Mode (DMODE) burst size.
3. The chip has enough bytes in the DMA FIFO to complete at least
one full cache line burst.
4. The chip is aligned to a cache line boundary.
When these conditions are met, the SYM53C896 issues a Write and
Invalidate command instead of a Memory Write command during all PCI
write cycles.
2-8
Functional Description
Multiple Cache Line Transfers – The Memory Write and Invalidate
command can write multiple cache lines of data in a single bus
ownership. The chip issues a burst transfer as soon as it reaches a
cache line boundary. The size of the transfer is not automatically the
cache line size, but rather a multiple of the cache line size specified in
Revision 2.1 of the PCI specification. The logic selects the largest
multiple of the cache line size based on the amount of data to transfer,
with the maximum allowable burst size determined from the DMA Mode
(DMODE) burst size bits, and Chip Test Five (CTEST5), bit 2. If multiple
cache line size transfers are not desired, set the DMODE burst size to
exactly the cache line size and the chip only issues single cache line
transfers.
After each data transfer, the chip re-evaluates the burst size based on
the amount of remaining data to transfer and again selects the highest
possible multiple of the cache line size, and no larger than the DMA
Mode (DMODE) burst size. The most likely scenario of this scheme is that
the chip selects the DMODE burst size after alignment, and issues bursts
of this size. The burst size is, in effect, throttled down toward the end of
a long Memory Move or Block Move transfer until only the cache line size
burst size is left. The chip finishes the transfer with this burst size.
Latency – In accordance with the PCI specification, the latency timer is
ignored when issuing a Memory Write and Invalidate command such that
when a latency time-out occurs, the SYM53C896 continues to transfer
up to a cache line boundary. At that point, the chip relinquishes the bus,
and finishes the transfer at a later time using another bus ownership. If
the chip is transferring multiple cache lines it continues to transfer until
the next cache boundary is reached.
PCI Target Retry – During a Memory Write and Invalidate transfer, if the
target device issues a retry (STOP with no TRDY/, indicating that no data
was transferred), the chip relinquishes the bus and immediately tries to
finish the transfer on another bus ownership. The chip issues another
Memory Write and Invalidate command on the next ownership, in
accordance with the PCI specification.
PCI Target Disconnect – During a Memory Write and Invalidate
transfer, if the target device issues a disconnect the SYM53C896
relinquishes the bus and immediately tries to finish the transfer on
another bus ownership. The chip does not issue another Memory Write
PCI Functional Description
2-9
and Invalidate command on the next ownership unless the address is
aligned.
2.1.3 Internal Arbiter
The PCI to SCSI controller uses a single REQ/ - GNT/ signal pair to
arbitrate for access to the PCI bus. An internal arbiter circuit allows the
different bus mastering functions resident in the chip to arbitrate among
themselves for the privilege of arbitrating for PCI bus access. There are
two independent bus mastering functions inside the SYM53C896, one for
each of the SCSI functions.
The internal arbiter uses a round robin arbitration scheme to decide
which internal bus mastering function may arbitrate for access to the PCI
bus. This ensures that no function is starved for access to the PCI bus.
2.1.4 PCI Cache Mode
The SYM53C896 supports the PCI specification for an 8-bit Cache Line
Size register located in the PCI configuration space. The Cache Line Size
register provides the ability to sense and react to nonaligned addresses
corresponding to cache line boundaries. In conjunction with the Cache
Line Size register, the PCI commands Memory Read Line, Memory Read
Multiple, Memory Write and Invalidate are each software enabled or
disabled to allow the user full flexibility in using these commands.
2.1.4.1 Enabling Cache Mode
For the cache logic to be enabled to issue PCI cache commands
(Memory Read Line, Memory Read Multiple, and Memory Write and
Invalidate) on any given PCI master operation the following conditions
must be met:
•
•
The Cache Line Size Enable bit in the DMA Control (DCNTL) register
must be set.
The PCI Cache Line Size register must contain a valid binary cache
size, i.e. 2, 4, 8, 16, 32, 64, or 128 dwords. Only these values are
considered valid cache sizes.
•
The programmed burst size (in dwords) must be equal to or greater
than the cache line size register. The DMA Mode (DMODE) register
bits [7:6] and the Chip Test Five (CTEST5) register bit 2 are the burst
length bits.
2-10
Functional Description
•
The part must be doing a PCI Master transfer. The following PCI
Master transactions do not utilize the PCI cache logic and thus no
PCI cache commands will be issued during these types of cycles: a
nonprefetch SCRIPTS fetch, a Load/Store data transfer, a data flush
operation. All other types of PCI Master transactions will utilize the
PCI cache logic.
The above four conditions must be met for the cache logic to control the
type of PCI cache command that is issued, along with any alignment that
may be necessary during write operations. If these conditions are not
met for any given PCI Master transaction, a Memory Read or Memory
Write will be issued and no cache write alignment will be done.
2.1.4.2 Issuing Cache Commands
In order to issue each type of PCI cache command, the corresponding
enable bit must be set (2 bits in the case of Memory Write and
Invalidate).
•
•
•
To issue Memory Read Line commands, set the Memory Read Line
enable bit in the DMA Mode (DMODE) register.
To issue Memory Read Multiple commands, set the Read Multiple
enable bit in the DMA Mode (DMODE) register.
To issue Memory Write and Invalidate commands, set the Write and
Invalidate enables in both the Chip Test Three (CTEST3) and the PCI
configuration Command registers.
If the corresponding cache command that is to be issued is not enabled
then the cache logic will fall back to the next command enabled, i.e., if
Memory Read Multiple is not enabled and Memory Read Lines are, read
lines will be issued in place of read multiples. If no cache commands are
enabled, cache write alignment will still occur but no cache commands
will be issued, only memory reads and memory writes will be issued.
2.1.4.3 Memory Read Caching
Which type of Memory Read command gets issued depends on the
starting location of the transfer and the number of bytes to be transferred.
During reads, no cache alignment is done (this is not required nor
optimal per PCI 2.1 specification) and reads will always be either a
programmed burst length in size, as set in the DMA Mode (DMODE) and
PCI Functional Description
2-11
Chip Test Three (CTEST3) registers. In the case of a transfer which is
smaller than the burst length, all bytes for that transfer will be read in one
PCI burst transaction. If the transfer will cross a dword boundary
(A[1:0] = 0b00) a Memory Read Line command is issued. When the
transfer will cross a cache boundary (depends on the cache line size
programmed into the PCI configuration register), a Memory Read
Multiple command is issued. If a transfer will not cross a dword or cache
boundary or if cache mode is not enabled a Memory Read command is
issued.
2.1.4.4 Memory Write Caching
Writes will be aligned in a single burst transfer to get to a cache
boundary. At that point, Memory Write and Invalidate commands will be
issued and will continue at the burst length programmed into the DMA
Mode (DMODE) register. Memory Write and Invalidate commands are
issued as long as the remaining byte count is greater than the Memory
Write and Invalidate threshold. When the byte count goes below this
threshold, a single Memory Write burst will be issued to complete the
transfer. The general pattern for PCI writes will is:
•
•
•
A single Memory Write to align to a cache boundary.
Multiple Memory Write and Invalidates.
A single data residual Memory Write to complete the transfer.
2-12
Functional Description
Table 2.2
PCI Cache Mode Alignment
Host Memory
A
00h
04h
08h
0Ch
10h
14h
18h
1Ch
20h
24h
28h
2Ch
30h
34h
38h
3Ch
40h
44h
48h
4Ch
50h
54h
58h
5Ch
60h
B
C
D
E
F
G
H
PCI Functional Description
2-13
2.1.4.5 Examples:
MR = Memory Read, MRL = Memory Read Line, MRM = Memory Read
Multiple, MW = Memory Write, MWI = Memory Write and Invalidate.
Read Example 1 –
Burst = 4 dwords, Cache Line Size = 4 dwords:
A to B:
A to C:
A to D:
MRL (6 bytes)
MRL (13 bytes)
MRL (15 bytes)
MR (2 bytes)
C to D:
C to E:
MRM (5 bytes)
MRM (15 bytes)
MRM (6 bytes)
D to F:
A to H:
MRL (15 bytes)
MRL (16 bytes)
MR (1 byte)
MRL (15 bytes)
MRL (16 bytes)
MRL (16 bytes)
MRL (16 bytes)
MRL (16 bytes)
MR (2 bytes)
A to G:
MRL (15 bytes)
MRL (16 bytes)
MRL (16 bytes)
MRL (16 bytes)
MR (3 bytes)
2-14
Functional Description
Read Example 2 –
Burst = 8 dwords, Cache Line Size = 4 dwords:
A to B:
A to C:
A to D:
C to D:
C to E:
D to F:
MRL (6 bytes)
MRL (13 bytes)
MRM (17 bytes)
MRM (5 bytes)
MRM (21 bytes)
MRM (31 bytes)
MR (1 byte)
A to H:
A to G:
MRM (31 bytes)
MRM (32 bytes)
MRM (18 bytes)
MRM (31 bytes)
MRM (32 bytes)
MR (3 bytes)
Read Example 3 –
Burst = 16 dwords, Cache Line Size = 8 dwords:
A to B:
A to C:
A to D:
C to D:
C to E:
D to F:
A to H:
MRL (6 bytes)
MRL (13 bytes)
MRL (17 bytes)
MRL (5 bytes)
MRM (21 bytes)
MRM (32 bytes)
MRM (63 bytes)
MRL (16 bytes)
MRM (2 bytes)
A to G:
MRM (63 bytes)
MR(3 bytes)
PCI Functional Description
2-15
Write Example 1 –
Burst = 4 dwords, Cache Line Size = 4 dwords:
A to B:
A to C:
A to D:
C to D:
C to E:
MW (6 bytes)
MW (13 bytes)
MW (17 bytes)
MW (5 bytes)
MW (3 bytes)
MWI (16 bytes)
MW (2 bytes)
D to F:
A to H:
MW (15 bytes)
MWI (16 bytes)
MW (1 byte)
MW (15 bytes)
MWI (16 bytes)
MWI (16 bytes)
MWI (16 bytes)
MWI (16 bytes)
MW (2 bytes)
A to G:
MW (15 bytes)
MWI (16 bytes)
MWI (16 bytes)
MWI (16 bytes)
MW (3 bytes)
Write Example 2 –
Burst = 8 dwords, Cache Line Size = 4 dwords:
A to B:
A to C:
A to D:
C to D:
C to E:
MW (6 bytes)
MW (13 bytes)
MW (17 bytes)
MW (5 bytes)
MW (3 bytes)
MWI (16 bytes)
MW (2 bytes)
D to F:
MW (15 bytes)
MWI (16 bytes)
MW (1 byte)
2-16
Functional Description
A to H:
A to G:
MW (15 bytes)
MWI (32 bytes)
MWI (32 bytes)
MW (2 bytes)
MW (15 bytes)
MWI (32 bytes)
MWI (16 bytes)
MW (3 bytes)
Write Example 3 –
Burst = 16 dwords, Cache Line Size = 8 dwords:
A to B:
A to C:
A to D:
C to D:
C to E:
D to F:
A to H:
MW (6 bytes)
MW (13 bytes)
MW (17 bytes)
MW (5 bytes)
MW (21 bytes)
MW (32 bytes)
MW (15 bytes)
MWI (64 bytes)
MW (2 bytes)
A to G:
MW (15 bytes)
MWI (32 bytes)
MW (18 bytes)
2.1.4.6 Memory-to-Memory Moves
Memory-to-Memory Moves also support PCI cache commands, as
described above, with one limitation: Memory Write and Invalidate on
Memory-to-Memory Move writes are only supported if the source and
destination address are quad word aligned. If the source and destination
are not quad word aligned, that is, Source address[2:0] == Destination
Address[2:0], write aligning is not performed and no Memory Write and
Invalidate commands are issued. The SYM53C896 is little endian only.
PCI Functional Description
2-17
2.2 SCSI Functional Description
The SYM53C896 provides two Ultra2 SCSI controllers on a single chip.
Each Ultra2 SCSI controller provides a SCSI function that supports an
8-bit or 16-bit bus. Each controller supports Wide Ultra2 SCSI
synchronous transfer rates up to 80 Mbytes/s on a LVD SCSI bus. SCSI
functions can be programmed with SCSI SCRIPTS, making it easy to
“fine tune” the system for specific mass storage devices or Ultra2 SCSI
requirements.
The SYM53C896 offers low level register access or a high-level control
interface. Like first generation SCSI devices, the SYM53C896 is
accessed as a register-oriented device. The ability to sample and/or
assert any signal on the SCSI bus is used in error recovery and
diagnostic procedures. In support of SCSI loopback diagnostics, each
SCSI function may perform a self-selection and operate as both an
initiator and a target.
The SYM53C896 is controlled by the integrated SCRIPTS processor
through a high-level logical interface. Commands controlling the SCSI
functions are fetched out of the main host memory or local memory.
These commands instruct the SCSI functions to Select, Reselect,
Disconnect, Wait for a Disconnect, Transfer Information, Change Bus
Phases and, in general, implement all aspects of the SCSI protocol. The
SCRIPTS processor is a special high-speed processor optimized for
SCSI protocol.
2.2.1 SCRIPTS Processor
The SCSI SCRIPTS processor allows both DMA and SCSI commands
to be fetched from host memory or internal SCRIPTS RAM. Algorithms
written in SCSI SCRIPTS control the actions of the SCSI and DMA
cores. The SCRIPTS processor executes complex SCSI bus sequences
independently of the host CPU.
Algorithms may be designed to tune SCSI bus performance, to adjust to
new bus device types (such as scanners, communication gateways, etc.),
or to incorporate changes in the SCSI-2 or SCSI-3 logical bus definitions
without sacrificing I/O performance. SCSI SCRIPTS are hardware
independent, so they can be used interchangeably on any host or CPU
2-18
Functional Description
system bus. SCSI SCRIPTS also handle conditions such as Phase
Mismatch.
2.2.1.1 Phase Mismatch Handling in SCRIPTS
The SYM53C896 can handle phase mismatches due to drive
disconnects without needing to interrupt the processor. The primary goal
of this logic is to completely eliminate the need for CPU intervention
during an I/O disconnect/reselect sequence.
Storing the appropriate information to later restart the I/O can be done
through SCRIPTS, eliminating the need for processor intervention during
an I/O disconnect/reselect sequence. Calculations are performed such
that the appropriate information is available to SCRIPTS so that an I/O
state can be properly stored for restart later.
The Phase Mismatch Jump logic powers up disabled and must be
enabled by setting the Phase Mismatch Jump Enable bit (ENPMJ, bit 7
in the Chip Control 0 (CCNTL0) register).
Utilizing the information supplied in the Phase Mismatch Jump Address 1
(PMJAD1) and Phase Mismatch Jump Address 2 (PMJAD2) registers,
described in Chapter 4, “Registers”, allows all overhead involved in a
disconnect/reselect sequence to be handled with a modest amount of
SCRIPTS instructions.
2.2.2 Internal SCRIPTS RAM
The SYM53C896 has 8 Kbytes (2048 x 32 bits) of internal, general
purpose RAM for each SCSI function. The RAM is designed for
SCRIPTS program storage, but is not limited to this type of information.
When the chip fetches SCRIPTS instructions or Table Indirect information
from the internal RAM, these fetches remain internal to the chip and do
not use the PCI bus. Other types of access to the RAM by the chip,
except Load/Store, use the PCI bus as if they were external accesses.
The SCRIPTS RAM powers up enabled by default.
The RAM can be relocated by the PCI system BIOS anywhere in the
64-bit address space. Base Address Register Two (SCRIPTS RAM) in the
PCI configuration space contains the base address of the internal RAM.
To simplify loading of the SCRIPTS instructions, the base address of the
RAM appears in the Scratch Register B (SCRATCHB) register when bit 3
SCSI Functional Description
2-19
of the Chip Test Two (CTEST2) register is set. The upper 32 bits of a 64-
bit base address will be in the SCRIPTS Fetch Selector (SFS) register.
The RAM is byte accessible from the PCI bus and is visible to any bus
mastering device on the bus. External accesses to the RAM (by the
CPU) follow the same timing sequence as a standard slave register
access, except that the required target wait-states drop from 5 to 3.
A complete set of development tools is available for writing custom
drivers with SCSI SCRIPTS. For more information on the SCSI SCRIPTS
instructions supported by the SYM53C896, see Chapter 5, “SCSI
SCRIPTS Instruction Set”.
2.2.3 64-Bit Addressing in SCRIPTS
The SYM53C896 has a 64-bit PCI interface which provides 64-bit
address and data capability in the initiator mode. The chip can also
respond to 64-bit addressing in the target mode.
DACs can be generated for all SCRIPTS operations. There are six
selector registers which hold the upper dword of a 64-bit address. All but
one of these is static and requires manual loading using a CPU access,
a Load/Store instruction, or a memory move instruction. One of the
selector registers is dynamic and is used during 64-bit direct block moves
only. All selectors will default to zero, meaning the SYM53C896 will
power-up in a state where only Single Address Cycles (SACs) will be
generated. When any of the selector registers are written to a nonzero
value, DACs will be generated.
Direct, table indirect and indirect block moves, Memory-to-Memory
Moves, Load/Stores and jumps are all instructions with 64-bit address
capability.
Crossing the 4 Gbyte boundary on any one SCRIPTS operation is not
permitted and software needs to take care that any given SCRIPTS
operation will not cross the 4 Gbyte boundary.
2.2.4 Hardware Control of SCSI Activity LED
The SYM53C896 has the ability to control a LED through the GPIO_0
pin to indicate that it is connected to the SCSI bus. Formerly this function
was done by a software driver.
2-20
Functional Description
When bit 5 (LED_CNTL) in the General Purpose Pin Control (GPCNTL)
register is set and bit 6 (Fetch Enable) in the GPCNTL register is cleared
and the SYM53C896 is not performing an EEPROM autodownload, then
bit 3 (CON) in the Interrupt Status Zero (ISTAT0) register will be presented
at the GPIO_0 pin.
The CON (Connected) bit in Interrupt Status Zero (ISTAT0) will be set
anytime the SYM53C896 is connected to the SCSI bus either as an
initiator or a target. This will happen after the SYM53C896 has
successfully completed a selection or when it has successfully
responded to a selection or reselection. It will also be set when the
SYM53C896 wins arbitration in low level mode.
2.2.5 Designing an Ultra2 SCSI System
Since Ultra2 SCSI is based on existing SCSI standards, it can use
existing driver programs as long as the software is able to negotiate for
Ultra2 SCSI synchronous transfer rates. Additional software
modifications may be needed to take advantage of the new features in
the SYM53C896.
In the area of hardware, LVD SCSI is required to achieve Ultra2 SCSI
transfer rates and to support the longer cable and additional devices on
the bus. All devices on the bus must have LVD SCSI capabilities to
guarantee Ultra2 SCSI transfer rates. For additional information on Ultra2
SCSI, refer to the SPI-2 working document which is available from the
SCSI BBS referenced at the beginning of this manual. Chapter 6,
“Specifications” contains Ultra2 SCSI timing information. In addition to the
guidelines in the draft standard, make the following software and
hardware adjustments to accommodate Ultra2 SCSI transfers:
•
•
Set the Ultra Enable bit to enable Ultra2 SCSI transfers.
Set the TolerANT Enable bit, bit 7 in the SCSI Test Three (STEST3)
register, whenever the Ultra Enable bit is set.
•
Do not extend the SREQ/SACK filtering period with the SCSI Test
Two (STEST2) register bit 1. When the Ultra Enable bit is set, the
filtering period will be fixed at 8 ns for Ultra2 SCSI or 15 ns for Ultra
SCSI, regardless of the value of the SREQ/SACK filtering bit.
•
Use the SCSI clock quadrupler.
SCSI Functional Description
2-21
2.2.5.1 Using the SCSI Clock Quadrupler
The SYM53C896 can quadruple the frequency of a 40 MHz SCSI clock,
allowing the system to perform Ultra2 SCSI transfers. This option is user
selectable with bit settings in the SCSI Test One (STEST1), SCSI Test
Three (STEST3), and SCSI Control Three (SCNTL3) registers. At
power-on or reset, the quadrupler is disabled and powered down. Follow
these steps to use the clock quadrupler:
1. Set the SCLK Quadrupler Enable bit (SCSI Test One (STEST1)
register, bit 3).
2. Poll bit 5 of the SCSI Test Four (STEST4) register. The SYM53C896
sets this bit as soon as it locks in the 160 MHz frequency. The
frequency lockin takes approximately 100 microseconds.
3. Halt the SCSI clock by setting the Halt SCSI Clock bit (SCSI Test
Three (STEST3) register, bit 5).
4. Set the clock conversion factor using the SCF and CCF fields in the
SCSI Control Three (SCNTL3) register.
5. Set the SCLK Quadrupler Select bit (SCSI Test One (STEST1), bit 2).
6. Clear the Halt SCSI Clock bit.
2.2.6 Prefetching SCRIPTS Instructions
When enabled by setting the Prefetch Enable bit (bit 5) in the DMA
Control (DCNTL) register, the prefetch logic in the SYM53C896 fetches 8
dwords of instruction. The prefetch logic automatically determines the
maximum burst size that it can perform, based on the burst length as
determined by the values in the DMA Mode (DMODE) register. If the unit
cannot perform bursts of at least four dwords, it disables itself. While the
chip is prefetching SCRIPTS instructions, it will use PCI cache
commands Memory Read Line, and Memory Read Multiple, if PCI
caching is enabled.
Note:
This feature is only useful when fetching SCRIPTS
instructions from main memory. Due to the short access
time of SCRIPTS RAM, prefetching is not necessary when
fetching instructions from this memory.
The SYM53C896 may flush the contents of the prefetch unit under
certain conditions to ensure that the chip always operates from the most
current version of the SCRIPTS instruction. When one of these
2-22
Functional Description
conditions applies, the contents of the prefetch unit are automatically
flushed.
•
On every Memory Move instruction. The Memory Move instruction is
often used to place modified code directly into memory. To make
sure that the chip executes all recent modifications, the prefetch unit
flushes its contents and loads the modified code every time an
instruction is issued. To avoid inadvertently flushing the prefetch unit
contents, use the No Flush option for all Memory Move operations
that do not modify code within the next 8 dwords. For more
information on this instruction refer to Chapter 5, “SCSI SCRIPTS
Instruction Set”.
•
On every Store instruction. The Store instruction may also be used
to place modified code directly into memory. To avoid inadvertently
flushing the prefetch unit contents use the No Flush option for all
Store operations that do not modify code within the next 8 dwords.
•
•
On every write to the DMA SCRIPTS Pointer (DSP) register.
On all Transfer Control instructions when the transfer conditions are
met. This is necessary because the next instruction to execute is not
the sequential next instruction in the prefetch unit.
•
When the Prefetch Flush bit (DMA Control (DCNTL) register, bit 6) is
set. The unit flushes whenever this bit is set. The bit is self-clearing.
2.2.7 Opcode Fetch Burst Capability
Setting the Burst Opcode Fetch Enable bit (bit 1) in the DMA Mode
(DMODE) register (0x38) causes the SYM53C896 to burst in the first two
dwords of all instruction fetches. If the instruction is a Memory-to-
Memory Move, the third dword is accessed in a separate ownership. If
the instruction is an Indirect Type, the additional dword is accessed in a
subsequent bus ownership. If the instruction is a table indirect Block
Move, the chip uses two accesses to obtain the four dwords required, in
two bursts of two dwords each.
Note:
This feature is only useful if Prefetching is disabled.
This feature is only useful if fetching SCRIPTS instructions
from main memory. Due to the short access time of
SCRIPTS RAM, burst opcode fetching is not necessary
when fetching instructions from this memory.
SCSI Functional Description
2-23
2.2.8 Load/Store Instructions
The SYM53C896 supports the Load/Store instruction type, which
simplifies the movement of data between memory and the internal chip
registers. It also enables the chip to transfer bytes to addresses relative
to the Data Structure Address (DSA) register. Load/Store data transfers to
or from the SCRIPTS RAM will remain internal to the chip and will not
generate PCI bus cycles. While a Load/Store to or from SCRIPTS RAM
is occurring, any external PCI slave cycles that occur will be retried on
the PCI bus. This feature can be disabled by setting the DILS bit in the
Chip Control 0 (CCNTL0) register. For more information on the Load/Store
instructions refer to Chapter 5, “SCSI SCRIPTS Instruction Set”.
2.2.9 JTAG Boundary Scan Testing
The SYM53C896 includes support for JTAG boundary scan testing in
accordance with the IEEE 1149.1 specification with one exception, which
is explained in this section. This device accepts all required boundary
scan instructions including the optional CLAMP, HIGH-Z, and IDCODE
instructions.
The SYM53C896 uses an 8-bit instruction register to support all
boundary scan instructions. The data registers included in the device are
the Boundary Data register, the IDCODE register, and the Bypass
register. This device can handle a 10 MHz TCK frequency for TDO and
TDI.
Due to design constraints, the RST/ pin (system reset) always 3-states
the SCSI pins when it is asserted. Boundary scan logic does not control
this action, and this is not compliant with the specification. There are two
solutions that resolve this issue:
1. Use the RST/ pin as a boundary scan compliance pin. When the pin
is deasserted, the device is boundary scan compliant and when
asserted, the device is noncompliant. To maintain compliance the
RST/ pin must be driven high.
2. When RST/ is asserted during boundary scan testing the expected
output on the SCSI pins must be the HIGH-Z condition, and not what
is contained in the boundary scan data registers for the SCSI pin
output cells.
2-24
Functional Description
2.2.10 SCSI Loopback Mode
The SYM53C896 loopback mode allows testing of both initiator and
target functions and, in effect, lets the chip communicate with itself.
When the Loopback Enable bit is set in the SCSI Test Two (STEST2)
register, bit 4, the SYM53C896 allows control of all SCSI signals whether
the chip is operating in the initiator or target mode. For more information
®
on this mode of operation refer to the LSI Logic Symbios PCI to SCSI
I/O Processors Programming Guide.
2.2.11 Parity Options
The SYM53C896 implements a flexible parity scheme that allows control
of the parity sense, allows parity checking to be turned on or off, and has
the ability to deliberately send a byte with bad parity over the SCSI bus
to test parity error recovery procedures. Table 2.3 defines the bits that are
involved in parity control and observation. Table 2.4 describes the parity
control function of the Enable Parity Checking and Assert SCSI Even
Parity bits in the SCSI Control One (SCNTL1) register, bit 2.
Table 2.5 describes the options available when a parity error occurs.
Figure 2.2 shows where parity checking is done in the SYM53C896.
SCSI Functional Description
2-25
Table 2.3
Bit Name
Bits Used for Parity Control and Generation
Location
Description
Assert SATN/ on Parity SCSI Control Zero Causes the SYM53C896 to automatically assert SATN/
Errors
(SCNTL0), Bit 1
when it detects a SCSI parity error while operating as
an initiator.
Enable Parity
Checking
SCSI Control Zero Enables the SYM53C896 to check for parity errors.
(SCNTL0), Bit 3 The SYM53C896 checks for odd parity.
Assert Even SCSI Parity SCSI Control One Determines the SCSI parity sense generated by the
(SCNTL1), Bit 2 SYM53C896 to the SCSI bus.
Disable Halt on SATN/
or a Parity Error (Target (SCNTL1), Bit 5
Mode Only)
SCSI Control One Causes the SYM53C896 not to halt operations when a
parity error is detected in target mode.
Enable Parity Error
Interrupt
SCSI Interrupt
Enable Zero
(SIEN0), Bit 0
Determines whether the SYM53C896 generates an
interrupt when it detects a SCSI parity error.
Parity Error
SCSI Interrupt
Status Zero
This status bit is set whenever the SYM53C896 detects
a parity error on the SCSI bus.
(SIST0), Bit 0
Status of SCSI
Parity Signal
SCSI Status Zero This status bit represents the active high current state
(SSTAT0), Bit 0
of the SCSI SDP0 parity signal.
SCSI SDP1 Signal
SCSI Status Two
(SSTAT2), Bit 0
This bit represents the active high current state of the
SCSI SDP1 parity signal.
Latched SCSI Parity
SCSI Status Two
(SSTAT2), Bit 3
These bits reflect the SCSI odd parity signal
corresponding to the data latched into the SCSI Input
SCSI Status One Data Latch (SIDL) register.
(SSTAT1), Bit 3
Master Parity Error
Enable
Chip Test Four
(CTEST4), Bit 3
Enables parity checking during PCI master data
phases.
Master Data Parity Error DMA Status
(DSTAT), Bit 6
Set when the SYM53C896, as a PCI master, detects a
target device signaling a parity error during a data
phase.
Master Data Parity Error DMA Interrupt
By clearing this bit, a Master Data Parity Error does not
Interrupt Enable
Enable (DIEN), Bit cause assertion of INTA/ (or INTB/), but the status bit
6
is set in the DMA Status (DSTAT) register.
2-26
Functional Description
Table 2.4
SCSI Parity Control
EPC1
ASEP2
Description
0
0
Does not check for parity errors. Parity is generated when sending SCSI data.
Asserts odd parity when sending SCSI data.
0
1
1
1
0
1
Does not check for parity errors. Parity is generated when sending SCSI data.
Asserts even parity when sending SCSI data.
Checks for odd parity on SCSI data received. Parity is generated when
sending SCSI data. Asserts odd parity when sending SCSI data.
Checks for odd parity on SCSI data received. Parity is generated when
sending SCSI data. Asserts even parity when sending SCSI data.
1. EPC = Enable Parity Checking (bit 3 SCSI Control Zero (SCNTL0)).
2. ASEP = Assert SCSI Even Parity (bit 2 SCSI Control One (SCNTL1)).
Table 2.5
SCSI Parity Errors and Interrupts
DHP1
PAR2
Description
0
0
Halts when a parity error occurs in the target or initiator mode and does NOT
generate an interrupt.
0
1
1
1
0
1
Halts when a parity error occurs in the target mode and generates an interrupt
in the target or initiator mode.
Does not halt in target mode when a parity error occurs until the end of the
transfer. An interrupt is not generated.
Does not halt in target mode when a parity error occurs until the end of the
transfer. An interrupt is generated.
1. DHP = Disable Halt on SATN/ or Parity Error (bit 5 SCSI Control One (SCNTL1)).
2. PAR = Parity Error (bit 0 SCSI Interrupt Enable One (SIEN1)).
SCSI Functional Description
2-27
Figure 2.2 Parity Checking/Generation
Asynchronous
SCSI Send
Synchronous
SCSI Send
Synchronous
SCSI Receive
Asynchronous
SCSI Receive
PCI Interface**
G
PCI Interface**
X
PCI Interface**
G
PCI Interface**
X
DMA FIFO*
(64 Bits x 118)
DMA FIFO*
(64 Bits x 118)
DMA FIFO*
(64 Bits x 118)
DMA FIFO*
(64 Bits x 118)
X
SCSI FIFO*
(8 or 16 Bits x 31)
SODL Register*
SODL Register*
S
SIDL Register*
X
X
SODR Register*
S
SCSI Interface**
SCSI Interface**
SCSI Interface**
X - Check parity
G - Generate 32-bit even PCI parity
S - Generate 8-bit odd SCSI parity
* = No parity protection
** = Parity protected
SCSI Interface**
2.2.12 DMA FIFO
The DMA FIFO is 8 bytes wide by 118 transfers deep. The DMA FIFO is
illustrated in Figure 2.3. The default DMA FIFO size is 112 bytes to
assure compatibility with older products in the SYM53C8XX family.
The DMA FIFO size may be set to 944 bytes by setting the DMA FIFO
Size bit, bit 5, in the Chip Test Five (CTEST5) register.
2-28
Functional Description
Figure 2.3 DMA FIFO Sections
8 Bytes Wide
.
.
.
.
.
.
118
Transfers
Deep
8 Bits
8 Bits
8 Bits
8 Bits
8 Bits
8 Bits
8 Bits
8 Bits
Byte Lane 7 Byte Lane 6 Byte Lane 5 Byte Lane 4 Byte Lane 3 Byte Lane 2 Byte Lane 1 Byte Lane 0
The SYM53C896 supports 64-bit memory and automatically supports
misaligned DMA transfers. A 944-byte FIFO allows the SYM53C896 to
support 2, 4, 8, 16, 32, 64, or 128 dword bursts across the PCI bus
interface.
2.2.12.1 Data Paths
The data path through the SYM53C896 is dependent on whether data is
being moved into or out of the chip, and whether SCSI data is being
transferred asynchronously or synchronously.
Figure 2.4 shows how data is moved to/from the SCSI bus in each of the
different modes.
The following items determine if any bytes remain in the data path when
the chip halts an operation:
Asynchronous SCSI Send –
Step 1. If the DMA FIFO size is set to 112 bytes (bit 5 of the Chip Test
Five (CTEST5) register cleared), look at the DMA FIFO (DFIFO)
and DMA Byte Counter (DBC) registers and calculate if there
are bytes left in the DMA FIFO. To make this calculation,
subtract the seven least significant bits of the DBC register from
SCSI Functional Description
2-29
the 7-bit value of the DFIFO register. AND the result with 0x7F
for a byte count between zero and 112.
If the DMA FIFO size is set to 944 bytes (bit 5 of the Chip Test
Five (CTEST5) register is set), subtract the 10 least significant
bits of the DMA Byte Counter (DBC) register from the 10-bit
value of the DMA FIFO Byte Offset Counter, which consists of
bits [1:0] in the Chip Test Five (CTEST5) register and bits [7:0]
of the DMA FIFO (DFIFO) register. AND the result with 0x3FF
for a byte count between zero and 944.
Step 2. Read bit 5 in the SCSI Status Zero (SSTAT0) and SCSI Status
Two (SSTAT2) registers to determine if any bytes are left in the
SCSI Output Data Latch (SODL) register. If bit 5 is set in the
SSTAT0 or SSTAT2 register, then the least significant byte or
the most significant byte in the SODL register is full. Checking
this bit also reveals bytes left in the SODL register from a
Chained Move operation with an odd byte count.
Synchronous SCSI Send –
Step 1. If the DMA FIFO size is set to 112 bytes (bit 5 of the Chip Test
Five (CTEST5) register cleared), look at the DMA FIFO (DFIFO)
and DMA Byte Counter (DBC) registers and calculate if there
are bytes left in the DMA FIFO. To make this calculation,
subtract the seven least significant bits of the DBC register from
the 7-bit value of the DFIFO register. AND the result with 0x7F
for a byte count between zero and 112.
If the DMA FIFO size is set to 944 bytes (bit 5 of the Chip Test
Five (CTEST5) register is set), subtract the 10 least significant
bits of the DMA Byte Counter (DBC) register from the 10-bit
value of the DMA FIFO Byte Offset Counter, which consists of
bits [1:0] in the Chip Test Five (CTEST5) register and bits [7:0]
of the DMA FIFO (DFIFO) register. AND the result with 0x3FF
for a byte count between zero and 944.
Step 2. Read bit 5 in the SCSI Status Zero (SSTAT0) and SCSI Status
Two (SSTAT2) registers to determine if any bytes are left in the
SODL register. If bit 5 is set in the SSTAT0 or SSTAT2 register,
then the least significant byte or the most significant byte in the
SCSI Output Data Latch (SODL) register is full. Checking this bit
also reveals bytes left in the SODL register from a Chained
Move operation with an odd byte count.
2-30
Functional Description
Step 3. Read bit 6 in the SCSI Status Zero (SSTAT0) and SCSI Status
Two (SSTAT2) registers to determine if any bytes are left in the
SODR register (a hidden buffer register which is not
accessible). If bit 6 is set in the SSTAT0 or SSTAT2 register,
then the least significant byte or the most significant byte in the
SODR register is full.
Asynchronous SCSI Receive –
Step 1. If the DMA FIFO size is set to 112 bytes (bit 5 of the Chip Test
Five (CTEST5) register cleared), look at the DFIFO and DMA
Byte Counter (DBC) registers and calculate if there are bytes left
in the DMA FIFO. To make this calculation, subtract the seven
least significant bits of the DBC register from the 7-bit value of
the DMA FIFO (DFIFO) register. AND the result with 0x7F for a
byte count between zero and 112.
If the DMA FIFO size is set to 944 bytes (bit 5 of the Chip Test
Five (CTEST5) register is set), subtract the 10 least significant
bits of the DMA Byte Counter (DBC) register from the 10-bit
value of the DMA FIFO Byte Offset Counter, which consists of
bits [1:0] in the CTEST5 register and bits [7:0] of the DMA FIFO
(DFIFO) register. AND the result with 0x3FF for a byte count
between zero and 944.
Step 2. Read bit 7 in the SCSI Status Zero (SSTAT0) and SCSI Status
Two (SSTAT2) registers to determine if any bytes are left in the
SCSI Input Data Latch (SIDL) register. If bit 7 is set in the
SSTAT0 or SSTAT2 registers, then the least significant byte or
the most significant byte is full.
Step 3. If any wide transfers have been performed using the Chained
Move instruction, read the Wide SCSI Receive bit (SCSI Control
Two (SCNTL2), bit 0) to determine whether a byte is left in the
SCSI Wide Residue (SWIDE) register.
Synchronous SCSI Receive –
Step 1. If the DMA FIFO size is set to 112 bytes, subtract the seven
least significant bits of the DMA Byte Counter (DBC) register
from the 7-bit value of the DMA FIFO (DFIFO) register. AND the
result with 0x7F for a byte count between zero and 112.
SCSI Functional Description
2-31
If the DMA FIFO size is set to 944 bytes (bit 5 of the Chip Test
Five (CTEST5) register is set), subtract the 10 least significant
bits of the DMA Byte Counter (DBC) register from the 10-bit
value of the DMA FIFO Byte Offset Counter, which consists of
bits [1:0] in the CTEST5 register and bits [7:0] of the DMA FIFO
(DFIFO) register. AND the result with 0x3FF for a byte count
between zero and 944.
Step 2. Read the SCSI Status One (SSTAT1) register and examine bits
[7:4], the binary representation of the number of valid bytes in
the SCSI FIFO, to determine if any bytes are left in the SCSI
FIFO.
Step 3. If any wide transfers have been performed using the Chained
Move instruction, read the Wide SCSI Receive bit (SCSI Control
Two (SCNTL2), bit 0) to determine whether a byte is left in the
SCSI Wide Residue (SWIDE) register.
Figure 2.4 SYM53C896 Host Interface SCSI Data Paths
Asynchronous
SCSI Send
Synchronous
SCSI Send
Synchronous
SCSI Receive
Asynchronous
SCSI Receive
PCI Interface
PCI Interface
PCI Interface
PCI Interface
DMA FIFO
(8 Bytes x 118)
DMA FIFO
(8 Bytes x 118)
DMA FIFO
(8 Bytes x 118)
DMA FIFO
(8 Bytes x 118)
SWIDE Register
SWIDE Register
SCSI FIFO
(1 or 2 Bytes x 31)
SODL Register
SCSI Interface
SIDL Register
SCSI Interface
SODL Register
SODR Register
SCSI Interface
SCSI Interface
2.2.13 SCSI Bus Interface
The SYM53C896 performs SE and LVD transfers, and supports
traditional HVD operation when the chip is connected to external HVD
transceivers.
2-32
Functional Description
To support LVD SCSI, all SCSI data and control signals have both
negative and positive signal lines. The negative signals perform the SCSI
data and control function. In the SE mode they become virtual ground
drivers. In the HVD mode, the positive signals provide directional control
to the external transceivers. TolerANT technology provides signal filtering
at the inputs of SREQ/ and SACK/ to increase immunity to signal
reflections.
2.2.13.1 LVD Link Technology
To support greater device connectivity and a longer SCSI cable, the
SYM53C896 features LVD Link technology, the LSI Logic implementation
of LVD SCSI. LVD Link transceivers provide the inherent reliability of
differential SCSI, and a long-term migration path of faster SCSI transfer
rates.
LVD Link technology is based on current drive. Its low output current
reduces the power needed to drive the SCSI bus, so that the I/O drivers
can be integrated directly onto the chip. This reduces the cost and
complexity compared to traditional HVD designs. LVD Link lowers the
amplitude of noise reflections and allows higher transmission
frequencies.
The LSI Logic LVD Link transceivers operate in LVD or SE modes. They
allow the chip to detect a HVD signal when the chip is connected to
external HVD transceivers. The SYM53C896 automatically detects which
type of signal is connected, based on the voltage detected by the
DIFFSENS pin. Bits 7 and 6 of the SCSI Test Four (STEST4) register
contain the encoded value for the type of signal that is detected (LVD,
SE, or HVD). Please see the SCSI Test Four (STEST4) register
description for encoding and other bit information.
2.2.13.2 HVD Mode
To maintain backward compatibility with legacy systems, the
SYM53C896 can operate in the HVD mode (when the chip is connected
to external differential transceivers). In the HVD mode, the SD[15:0]+,
SDP[1:0]+, SREQ+, SACK+, SRST+, SBSY+, and SSEL+ signals control
the direction of external differential pair transceivers. The SYM53C896 is
placed in the HVD mode by setting the DIF bit, bit 5, of the SCSI Test
Two (STEST2) register (0x4E). Setting this bit 3-states the SBSY−,
SSEL−, and SRST− pads so they can be used as pure input pins. In
SCSI Functional Description
2-33
addition to the standard SCSI lines, the signals shown in Table 2.6 are
used by the SYM53C896 during HVD operation.
Table 2.6
Signal
HVD Signals
Function
SBSY+, SSEL+,
SRST+
Active high signals used to enable the differential drivers as outputs for SCSI
signals SBSY−, SSEL−, and SRST−, respectively.
SD[15:0]+,
SDP[1:0]+
Active high signals used to control the direction of the differential drivers for
SCSI data and parity lines, respectively.
SACK+
Active high signal used to control the direction of the differential drivers for
the initiator group signals SATN− and SACK−.
SREQ+
Active high signal used to control the direction of the differential drivers for
target group signals SMSG−, SC_D−, SI_O− and SREQ−.
DIFFSENS
Input to the SYM53C896 used to detect the voltage level of a SCSI signal to
determine whether it is a SE, LVD, or HVD signal. The encoded result is
displayed in SCSI Test Four (STEST4) bits 7 and 6.
In the example differential wiring diagram in Figure 2.5, the SYM53C896 is
connected to TI SN75976 differential transceivers for Ultra SCSI operation.
The recommended value of the pull-up resistor on the SREQ−, SACK−,
SMSG−, SC_D−, SI_O−, SATN−, SD[7:0]−, and SDP0− lines is 680 Ω
when the Active Negation portion of LSI Logic TolerANT technology is not
enabled. When TolerANT technology is enabled, the recommended
resistor value on the SREQ−, SACK−, SD[7:0]−, and SDP0− signals is
1.5 kΩ. The electrical characteristics of these pins change when TolerANT
technology is enabled, permitting a higher resistor value.
To interface the SYM53C896 to the SN75976A, connect the positive pins
in the SCSI LVD pair of the SYM53C896 directly to the transceiver
enables (DE/RE/). These signals control the direction of the channels on
the SN75976A.
The SCSI bidirectional control and data pins (SD[7:0]−, SDP0−, SREQ−,
SACK−, SMSG−, SI_O−, SC_D−, and SATN−) of the SYM53C896
connect to the bidirectional data pins (nA) of the SN75976A with a
pull-up resistor. The pull-up value should be no lower than the transceiver
I
can tolerate, but not so high as to cause RC timing problems. The
OL
three remaining pins, SSEL−, SBSY− and SRST−, are connected to the
SN75976A with a pull-down resistor. The pull-down resistors are required
2-34
Functional Description
when the pins (nA) of the SN75976A are configured as inputs. When the
data pins are inputs, the resistors provide a bias voltage to both the
SYM53C896 pins (SSEL−, SBSY−, and SRST−) and the SN75976A data
pins. Because the SSEL−, SBSY−, and SRST− pins on the SYM53C896
are inputs only, this configuration allows for the SSEL−, SBSY−, and
SRST− SCSI signals to be asserted on the SCSI bus.
The differential pairs on the SCSI bus are reversed when connected to
the SN75976A due to the active low nature of the SCSI bus.
8-bit/16-bit SCSI and the HVD Interface – In an 8-bit SCSI bus, the
SD[15:8] pins on the SYM53C896 should be pulled up with a 1.5 kΩ
resistor or terminated like the rest of the SCSI bus lines. This is very
important, as errors may occur during reselection if these lines are left
floating.
SCSI Functional Description
2-35
Figure 2.5 8-Bit HVD Wiring Diagram for Ultra SCSI
Schottky
Diode
DIFFSENS
DIFFSENS (pin 21)
VDD
SYM53C8XX
1.5 K
SN75976A2
−SEL (42)
CDE0
SEL+
1B+
1B−
2B+
2B−
3B+
3B−
4B+
4B−
5B+
5B−
6B+
6B−
7B+
7B−
8B+
8B−
9B+
9B−
1.5 K
(41)
(34)
(33)
(38)
(37)
+SEL
−BSY
+BSY
−RST
+RST
CDE1
CDE2
BSR
BSY+
RST+
CRE
SEL−
BSY−
RST−
1.5 K
SEL-
BSY-
RST-
1A
1DE/RE
2A
2DE/RE
3A
3DE/RE
4A
4DE/RE
5A
5DE/RE
6A
6DE/RE
7A
7DE/RE
8A
−REQ (46)
SEL+
BSY+
(45)
+REQ
(36)
−ACK
VDD
1.5 K
VDD
REQ−
+ACK (35)
(40)
(39)
(44)
−MSG
+MSG
−C/D
RST+
REQ/
ACK−
1.5 K
+C/D (43)
−I/O (48)
+I/O (47)
MSG−
C/D−
I/O−
VDD
ACK−
MSG−
(30)
(29)
−ATN
+ATN
1.5 K
ATN−
C_D−
I_O−
SCSI
Bus
REQ+
1.5 K
ACK+
8DE/RE
9A
9DE/RE
ATN-
SD[8:15]+
SDP1+
Float
Float
VDD
1.5 K
1.5 K
SD[8:15]−
SDP1−
SN75976A2
−DB0 (4)
DIFFSENS
CDE0
CDE1
CDE2
BSR
1B+
1B−
2B+
2B−
3B+
3B−
4B+
4B−
5B+
5B−
6B+
6B−
7B+
7B−
8B+
8B−
9B+
9B−
(3)
(6)
(5)
(8)
(7)
+DB0
−DB1
+DB1
−DB2
+DB2
VDD
1.5 K
SDP0+
SD7+
SD6+
SD5+
SD4+
SD3+
SD2+
SD1+
SD0+
1.5 K
SD0−
CRE
1A
1DE/RE
2A
2DE/RE
3A
3DE/RE
4A
4DE/RE
5A
5DE/RE
6A
6DE/RE
7A
7DE/RE
8A
−DB3 (10)
SD0+
SD1+
SD2+
SD3+
SD4+
SD5+
SD6+
SD7+
SDP0+
(9)
+DB3
SD1−
SD2−
SD3−
SD4−
SD5−
SD6−
SD7−
SDP0−
(12)
−DB4
+DB4 (11)
(14)
(13)
(16)
−DB5
+DB5
−DB6
+DB6 (15)
−DB7 (18)
+DB7 (17)
SDP0−
SD7−
SD6−
SD5−
SD4−
SD3−
SD2−
SD1−
SD0−
(20)
(19)
−DBP
+DBP
8DE/RE
9A
9DE/RE
DIFFSENS
DIFFSENS
2-36
Functional Description
2.2.13.3 SCSI Termination
The terminator networks provide the biasing needed to pull signals to an
inactive voltage level, and to match the impedance seen at the end of
the cable with the characteristic impedance of the cable. Terminators
must be installed at the extreme ends of the SCSI chain, and only at the
ends. No system should ever have more or less than two terminators
installed and active. SCSI host adapters should provide a means of
accommodating terminators. There should be a means of disabling the
termination.
SE cables can use a 220 Ω pull-up resistor to the terminator power
supply (Term Power) line and a 330 Ω pull-down resistor to ground.
Because of the high-performance nature of the SYM53C896, regulated
(or active) termination is recommended. Figure 2.6 shows a Unitrode
active terminator. TolerANT technology active negation can be used with
either termination network.
For information on terminators that support LVD, refer to the SPI-2 draft
standard.
Note:
If the SYM53C896 is to be used in a design with only an
8-bit SCSI bus, all 16 data lines must be terminated.
SCSI Functional Description
2-37
Figure 2.6 Regulated Termination for Ultra2 SCSI
UCC5630
SDP0−
SDP0+
SD7−
SD7+
SD6−
SD6+
SD0+
SD0−
SD1+
SD1−
SD2+
SD2−
SD3+
SD3−
SD4+
4
5
6
7
Line1+
Line1−
Line2+
Line2−
32
31
30
29
Line9−
Line9+
Line8−
Line8+
11 Line3+
12 Line3−
13 Line4+
14 Line4−
15 Line5+
16 Line5−
Line7− 25
24
Line7+
Line6− 23
SD5−
SD5+
22
Line6+
SD4−
SE 33
LVD 34
HVD 35
To LED
Drivers
DIFFSENS 20
17 DISCNCT
22 K
DIFF B 21
0.1 µF
DIFFSENS connects to the SCSI bus DIFFSENS line to detect what
type of devices (SE, LVD, or HVD) are connected to the SCSI bus.
DISCNCT shuts down the terminator when it is not at the end of the
bus. The disconnect pin low enables the terminator.
*Use additional UCC5630 terminators to terminate the SCSI control
signals and wide SCSI data byte as needed.
2.2.14 Select/Reselect During Selection/Reselection
In multithreaded SCSI I/O environments, it is not uncommon to be
selected or reselected while trying to perform selection/reselection. This
situation may occur when a SCSI controller (operating in the initiator
mode) tries to select a target and is reselected by another. The Select
SCRIPTS instruction has an alternate address to which the SCRIPTS will
jump when this situation occurs. The analogous situation for target
devices is being selected while trying to perform a reselection.
Once a change in operating mode occurs, the initiator SCRIPTS should
start with a Set Initiator instruction or the target SCRIPTS should start
with a Set Target instruction. The Selection and Reselection Enable bits
(SCSI Chip ID (SCID) bits 5 and 6, respectively) should both be asserted
2-38
Functional Description
so that the SYM53C896 may respond as an initiator or as a target. If only
selection is enabled, the SYM53C896 cannot be reselected as an
initiator. There are also status and interrupt bits in the SCSI Interrupt
Status Zero (SIST0) and SCSI Interrupt Enable Zero (SIEN0) registers,
respectively, indicating that the SYM53C896 has been selected (bit 5)
and reselected (bit 4).
2.2.15 Synchronous Operation
The SYM53C896 can transfer synchronous SCSI data in both the
initiator and target modes. The SCSI Transfer (SXFER) register controls
both the synchronous offset and the transfer period. It may be loaded by
the CPU before SCRIPTS execution begins, from within SCRIPTS using
a Table Indirect I/O instruction, or with a Read-Modify-Write instruction.
The SYM53C896 can receive data from the SCSI bus at a synchronous
transfer period as short as 25 ns, regardless of the transfer period used
to send data. The SYM53C896 can receive data at one-fourth of the
divided SCLK frequency. Depending on the SCLK frequency, the
negotiated transfer period, and the synchronous clock divider, the
SYM53C896 can send synchronous data at intervals as short as 25 ns
for Ultra2 SCSI, 50 ns for Ultra SCSI, 100 ns for fast SCSI and 200 ns
for SCSI-1.
2.2.15.1 Determining the Data Transfer Rate
Synchronous data transfer rates are controlled by bits in two different
registers of the SYM53C896. Following is a brief description of the bits.
Figure 2.7 illustrates the clock division factors used in each register, and
the role of the register bits in determining the transfer rate.
2.2.15.2 SCSI Control Three (SCNTL3) Register, bits [6:4] (SCF[2:0])
The SCF[2:0] bits select the factor by which the frequency of SCLK is
divided before being presented to the synchronous SCSI control logic.
The output from this divider controls the rate at which data can be
received. This rate must not exceed 160 MHz. The receive rate of
synchronous SCSI data is one-fourth of the SCF divider output. For
example, if SCLK is 160 MHz and the SCF value is set to divide by one,
then the maximum rate at which data can be received is 40 MHz
(160/(1*4) = 40).
SCSI Functional Description
2-39
2.2.15.3 SCSI Control Three (SCNTL3) Register, bits [2:0] (CCF[2:0])
The CCF[2:0] bits select the factor by which the frequency of SCLK is
divided before being presented to the asynchronous SCSI core logic.
This divider must be set according to the input clock frequency in the
table.
2.2.15.4 SCSI Transfer (SXFER) Register, bits [7:5] (TP[2:0])
The TP[2:0] divider bits determine the SCSI synchronous transfer period
when sending synchronous SCSI data in either the initiator or target
mode. This value further divides the output from the SCF divider.
2.2.15.5 Ultra2 SCSI Synchronous Data Transfers
Ultra2 SCSI is an extension of the current Ultra SCSI synchronous
transfer specifications. It allows synchronous transfer periods to be
negotiated down as low as 25 ns, which is half the 50 ns period allowed
under Ultra SCSI. This will allow a maximum transfer rate of 80 Mbytes/s
on a 16-bit, LVD SCSI bus. The SYM53C896 has a SCSI clock
quadrupler that must be enabled for the chip to perform Ultra2 SCSI
transfers with a 40 MHz oscillator. In addition, the following bit values
affect the chip’s ability to support Ultra2 SCSI synchronous transfer rates:
•
Clock Conversion Factor bits, SCSI Control Three (SCNTL3) register
bits [2:0] and Synchronous Clock Conversion Factor bits, SCNTL3
register bits [6:4]. These fields support a value of 111 (binary),
allowing the 160 MHz SCLK frequency to be divided down by 8 for
the asynchronous logic.
•
•
Ultra2 SCSI Enable bit, SCSI Control Three (SCNTL3) register bit 7.
Setting this bit enables Ultra2 SCSI synchronous transfers in
systems that use the internal SCSI clock quadrupler.
TolerANT Enable bit, SCSI Test Three (STEST3) register bit 7. Active
negation must be enabled for the SYM53C896 to perform Ultra2
SCSI transfers.
Note:
The clock quadrupler requires a 40 MHz external clock.
LSI Logic Symbios software assumes that the SYM53C896
is connected to a 40 MHz external clock, which is
quadrupled to achieve Ultra2 SCSI transfer rates.
2-40
Functional Description
Figure 2.7 Determining the Synchronous Transfer Rate
SCF2
SCF1
SCF0
SCF
TP2
TP1
TP0
XFERP
Divisor
Divisor
0
0
0
1
0
1
1
1
0
1
1
0
0
0
1
1
1
0
1
0
0
1
0
1
1
1.5
2
3
3
4
6
8
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
4
5
6
7
8
9
10
11
This point
must not
exceed
160 MHz
Divide by 4
Receive
Clock
Synchronous
Divider
Send Clock
(to SCSI Bus)
SCF
Divider
Clock
Quadrupler
SCLK
QCLK
CCF
Divider
Asynchronous
SCSI Logic
CCF2
CCF1
CCF0
Divisor
QCLK (MHz)
50.1–66.00
16.67–25.00
25.1–37.50
37.51–50.00
50.01–66.00
75.01–80.00
120
0
0
0
1
0
1
1
1
0
1
1
0
0
0
1
1
1
0
1
0
0
1
0
1
1
1.5
2
3
3
4
6
8
Example:
QCLK (Quadrupled SCSI Clock) = 160 MHz
SCF = 1 (/1), XFERP = 0 (/4), CCF = 7 (/8)
Synchronous send rate = (QCLK/SCF)/XFERP =
(160/1) /4 = 40 Mbytes/s
Synchronous receive rate = (QCLK/SCF) /4 =
(160/1) /4 = 40 Mbytes/s
160
2.2.16 Interrupt Handling
The SCRIPTS processors in the SYM53C896 perform most functions
independently of the host microprocessor. However, certain interrupt
situations must be handled by the external microprocessor. This section
explains all aspects of interrupts as they apply to the SYM53C896.
2.2.16.1 Polling and Hardware Interrupts
The external microprocessor is informed of an interrupt condition by
polling or hardware interrupts. Polling means that the microprocessor
must continually loop and read a register until it detects a bit that is set
indicating an interrupt. This method is the fastest, but it wastes CPU time
SCSI Functional Description
2-41
that could be used for other system tasks. The preferred method of
detecting interrupts in most systems is hardware interrupts. In this case,
the SYM53C896 asserts the Interrupt Request (INTA/ or INTB/) line that
interrupts the microprocessor, causing the microprocessor to execute an
interrupt service routine. A hybrid approach would use hardware
interrupts for long waits, and use polling for short waits.
SCSI Function A is routed to PCI Interrupt INTA/. SCSI Function B is
normally routed to INTB/, but can be routed to INTA/ if a pull-up is
connected to MAD[4]. See Section 3.7, “MAD Bus Programming” for
additional information.
2.2.16.2 Registers
The registers in the SYM53C896 that are used for detecting or defining
interrupts are ISTAT, SCSI Interrupt Status Zero (SIST0), SCSI Interrupt
Status One (SIST1), SCSI Interrupt Enable Zero (SIEN0), SCSI Interrupt
Enable One (SIEN1), DMA Control (DCNTL), and DMA Interrupt Enable
(DIEN).
ISTAT – The ISTAT register includes the Interrupt Status Zero (ISTAT0),
Interrupt Status One (ISTAT1), Mailbox Zero (MBOX0), and Mailbox One
(MBOX1) registers. It is the only register that can be accessed as a slave
during the SCRIPTS operation. Therefore, it is the register that is polled
when polled interrupts are used. It is also the first register that should be
read after the INTA/ (or INTB/) pin is asserted in association with a
hardware interrupt. The INTF (Interrupt-on-the-Fly) bit should be the first
interrupt serviced. It must be written to one to be cleared. This interrupt
must be cleared before servicing any other interrupts.
See Register 0x14, Interrupt Status Zero (ISTAT0), Bit 5 signal process in
Chapter 4, “Registers” for additional information.
The host (C Code) or the SCRIPTS code could potentially try to access
the mailbox bits at the same time.
If the SIP bit in the Interrupt Status Zero (ISTAT0) register is set, then a
SCSI-type interrupt has occurred and the SCSI Interrupt Status Zero
(SIST0) and SCSI Interrupt Status One (SIST1) registers should be read.
If the DIP bit in the Interrupt Status Zero (ISTAT0) register is set, then a
DMA-type interrupt has occurred and the DMA Status (DSTAT) register
should be read.
2-42
Functional Description
SCSI-type and DMA-type interrupts may occur simultaneously, so in
some cases both SIP and DIP may be set.
SIST0 and SIST1 – The SCSI Interrupt Status Zero (SIST0) and SCSI
Interrupt Status One (SIST1) registers contain SCSI-type interrupt bits.
Reading these registers determines which condition or conditions caused
the SCSI-type interrupt, and clears that SCSI interrupt condition.
If the SYM53C896 is receiving data from the SCSI bus and a fatal
interrupt condition occurs, the chip attempts to send the contents of the
DMA FIFO to memory before generating the interrupt.
If the SYM53C896 is sending data to the SCSI bus and a fatal SCSI
interrupt condition occurs, data could be left in the DMA FIFO. Because
of this the DMA FIFO Empty (DFE) bit in DMA Status (DSTAT) should be
checked.
If this bit is cleared, set the CLF (Clear DMA FIFO) and CSF (Clear SCSI
FIFO) bits before continuing. The CLF bit is bit 2 in Chip Test Three
(CTEST3). The CSF bit is bit 1 in SCSI Test Three (STEST3).
DSTAT – The DMA Status (DSTAT) register contains the DMA-type
interrupt bits. Reading this register determines which condition or
conditions caused the DMA-type interrupt, and clears that DMA interrupt
condition. Bit 7 in DSTAT, DFE, is purely a status bit; it will not generate
an interrupt under any circumstances and will not be cleared when read.
DMA interrupts flush neither the DMA nor SCSI FIFOs before generating
the interrupt, so the DFE bit in the DSTAT register should be checked
after any DMA interrupt.
If the DFE bit is cleared, then the FIFOs must be cleared by setting the
CLF (Clear DMA FIFO) and CSF (Clear SCSI FIFO) bits, or flushed by
setting the FLF (Flush DMA FIFO) bit.
SIEN0 and SIEN1 – The SCSI Interrupt Enable Zero (SIEN0) and SCSI
Interrupt Enable One (SIEN1) registers are the interrupt enable registers
for the SCSI interrupts in SCSI Interrupt Status Zero (SIST0) and SCSI
Interrupt Status One (SIST1).
DIEN – The DMA Interrupt Enable (DIEN) register is the interrupt enable
register for DMA interrupts in DMA Status (DSTAT).
SCSI Functional Description
2-43
DMA Control (DCNTL) – When bit 1 in this register is set, the INTA/ (or
INTB/) pin is not asserted when an interrupt condition occurs. The
interrupt is not lost or ignored, but is merely masked at the pin. Clearing
this bit when an interrupt is pending immediately causes the INTA/ (or
INTB/) pin to assert. As with any register other than ISTAT, this register
cannot be accessed except by a SCRIPTS instruction during SCRIPTS
execution.
2.2.16.3 Fatal vs. Nonfatal Interrupts
A fatal interrupt, as the name implies, always causes the SCRIPTS to
stop running. All nonfatal interrupts become fatal when they are enabled
by setting the appropriate interrupt enable bit. Interrupt masking is
discussed in Section 2.2.16.4, “Masking”. All DMA interrupts (indicated by
the DIP bit in Interrupt Status Zero (ISTAT0) and one or more bits in DMA
Status (DSTAT) being set) are fatal.
Some SCSI interrupts (indicated by the SIP bit in the Interrupt Status Zero
(ISTAT0) and one or more bits in SCSI Interrupt Status Zero (SIST0) or
SCSI Interrupt Status One (SIST1) being set) are nonfatal.
When the SYM53C896 is operating in the Initiator mode, only the
Function Complete (CMP), Selected (SEL), Reselected (RSL), General
Purpose Timer Expired (GEN), and Handshake-to-Handshake Timer
Expired (HTH) interrupts are nonfatal.
When operating in the Target mode, CMP, SEL, RSL, Target mode:
SATN/ active (M/A), GEN, and HTH are nonfatal. Refer to the description
for the Disable Halt on a Parity Error or SATN/ active (Target Mode Only)
(DHP) bit in the SCSI Control One (SCNTL1) register to configure the
chip’s behavior when the SATN/ interrupt is enabled during Target mode
operation. The Interrupt-on-the-Fly interrupt is also nonfatal, since
SCRIPTS can continue when it occurs.
The reason for nonfatal interrupts is to prevent the SCRIPTS from
stopping when an interrupt occurs that does not require service from the
CPU. This prevents an interrupt when arbitration is complete (CMP set),
when the SYM53C896 is selected or reselected (SEL or RSL set), when
the initiator asserts ATN (target mode: SATN/ active), or when the
General Purpose or Handshake-to-Handshake timers expire. These
interrupts are not needed for events that occur during high-level
SCRIPTS operation.
2-44
Functional Description
2.2.16.4 Masking
Masking an interrupt means disabling or ignoring that interrupt. Interrupts
can be masked by clearing bits in the SCSI Interrupt Enable Zero (SIEN0)
and SCSI Interrupt Enable One (SIEN1) (for SCSI interrupts) registers or
DMA Interrupt Enable (DIEN) (for DMA interrupts) register. How the chip
responds to masked interrupts depends on: whether polling or hardware
interrupts are being used; whether the interrupt is fatal or nonfatal; and
whether the chip is operating in the Initiator or Target mode.
If a nonfatal interrupt is masked and that condition occurs, the SCRIPTS
do not stop, the appropriate bit in the SCSI Interrupt Status Zero (SIST0)
or SCSI Interrupt Status One (SIST1) is still set, the SIP bit in the Interrupt
Status Zero (ISTAT0) is not set, and the INTA/ (or INTB/) pin is not
asserted.
If a fatal interrupt is masked and that condition occurs, then the SCRIPTS
still stop, the appropriate bit in the DMA Status (DSTAT), SCSI Interrupt
Status Zero (SIST0), or SCSI Interrupt Status One (SIST1) register is set,
and the SIP or DIP bit in the Interrupt Status Zero (ISTAT0) register is set,
but the INTA/ (or INTB/) pin is not asserted.
Interrupts can be disabled by setting the SYNC_IRQD bit in the Interrupt
Status One (ISTAT1) register. If an interrupt is already asserted and
SYNC_IRQD is then set, the interrupt will remain until serviced. Further
interrupts will be blocked.
When the SYM53C896 is initialized, enable all fatal interrupts if hardware
interrupts are being used. If a fatal interrupt is disabled and that interrupt
condition occurs, the SCRIPTS halts and the system never knows it
unless it times out and checks the Interrupt Status Zero (ISTAT0), Interrupt
Status One (ISTAT1), Mailbox Zero (MBOX0), and Mailbox One (MBOX1)
registers after a certain period of inactivity.
If ISTAT is being polled instead of using hardware interrupts, then
masking a fatal interrupt makes no difference since the SIP and DIP bits
in the Interrupt Status Zero (ISTAT0) inform the system of interrupts, not
the INTA/ (or INTB/) pin.
Masking an interrupt after INTA/ (or INTB/) is asserted does not cause
deassertion of INTA/ (or INTB/).
SCSI Functional Description
2-45
2.2.16.5 Stacked Interrupts
The SYM53C896 will stack interrupts, if they occur, one after the other.
If the SIP or DIP bits in the Interrupt Status Zero (ISTAT0) register are set
(first level), then there is already at least one pending interrupt, and any
future interrupts are stacked in extra registers behind the SCSI Interrupt
Status Zero (SIST0), SCSI Interrupt Status One (SIST1), and DMA Status
(DSTAT) registers (second level). When two interrupts have occurred and
the two levels of the stack are full, any further interrupts set additional
bits in the extra registers behind SIST0, SIST1, and DSTAT. When the
first level of interrupts are cleared, all the interrupts that came in
afterward move into SIST0, SIST1, and DSTAT. After the first interrupt is
cleared by reading the appropriate register, the INTA/ (or INTB/) pin is
deasserted for a minimum of three CLKs; the stacked interrupts move
into SIST0, SIST1, or DSTAT; and the INTA/ (or INTB/) pin is asserted
once again.
Since a masked nonfatal interrupt does not set the SIP or DIP bits,
interrupt stacking does not occur. A masked, nonfatal interrupt still posts
the interrupt in SCSI Interrupt Status Zero (SIST0), but does not assert the
INTA/ (or INTB/) pin. Since no interrupt is generated, future interrupts
move into SIST0 or SCSI Interrupt Status One (SIST1) instead of being
stacked behind another interrupt. When another condition occurs that
generates an interrupt, the bit corresponding to the earlier masked
nonfatal interrupt is still set.
A related situation to interrupt stacking is when two interrupts occur
simultaneously. Since stacking does not occur until the SIP or DIP bits
are set, there is a small timing window in which multiple interrupts can
occur but are not stacked. These could be multiple SCSI interrupts (SIP
set), multiple DMA interrupts (DIP set), or multiple SCSI and multiple
DMA interrupts (both SIP and DIP set).
As previously mentioned, DMA interrupts do not attempt to flush the
FIFOs before generating the interrupt. It is important to set either the
Clear DMA FIFO (CLF) and Clear SCSI FIFO (CSF) bits if a DMA
interrupt occurs and the DMA FIFO Empty (DFE) bit is not set. This is
because any future SCSI interrupts are not posted until the DMA FIFO
is cleared of data. These ‘locked out’ SCSI interrupts are posted as soon
as the DMA FIFO is empty.
2-46
Functional Description
2.2.16.6 Halting in an Orderly Fashion
When an interrupt occurs, the SYM53C896 attempts to halt in an orderly
fashion.
•
If the interrupt occurs in the middle of an instruction fetch, the fetch
is completed, except in the case of a Bus Fault. Execution does not
begin, but the DSP points to the next instruction since it is updated
when the current instruction is fetched.
•
If the DMA direction is a write to memory and a SCSI interrupt
occurs, the SYM53C896 attempts to flush the DMA FIFO to memory
before halting. Under any other circumstances only the current cycle
is completed before halting, so the DFE bit in DMA Status (DSTAT)
should be checked to see if any data remains in the DMA FIFO.
•
•
•
•
SCSI SREQ/SACK handshakes that have begun are completed
before halting.
The SYM53C896 attempts to clean up any outstanding synchronous
offset before halting.
In the case of Transfer Control Instructions, once instruction
execution begins it continues to completion before halting.
If the instruction is a JUMP/CALL WHEN/IF <phase>, the DMA
SCRIPTS Pointer (DSP) is updated to the transfer address before
halting.
•
All other instructions may halt before completion.
2.2.16.7 Sample Interrupt Service Routine
The following is a sample of an interrupt service routine for the
SYM53C896. It can be repeated if polling is used, or should be called
when the INTA/ (or INTB/) pin is asserted if hardware interrupts are used.
1. Read Interrupt Status Zero (ISTAT0).
2. If the INTF bit is set, it must be written to a one to clear this status.
3. If only the SIP bit is set, read SCSI Interrupt Status Zero (SIST0) and
SCSI Interrupt Status One (SIST1) to clear the SCSI interrupt
condition and get the SCSI interrupt status. The bits in the SIST0
and SIST1 tell which SCSI interrupts occurred and determine what
action is required to service the interrupts.
SCSI Functional Description
2-47
4. If only the DIP bit is set, read DMA Status (DSTAT) to clear the
interrupt condition and get the DMA interrupt status. The bits in
DSTAT tell which DMA interrupts occurred and determine what action
is required to service the interrupts.
5. If both the SIP and DIP bits are set, read SCSI Interrupt Status Zero
(SIST0), SCSI Interrupt Status One (SIST1), and DMA Status (DSTAT)
to clear the SCSI and DMA interrupt condition and get the interrupt
status. If using 8-bit reads of the SIST0, SIST1, and DSTAT registers
to clear interrupts, insert a 12 clock delay between the consecutive
reads to ensure that the interrupts clear properly. Both the SCSI and
DMA interrupt conditions should be handled before leaving the
Interrupt Service Routine. It is recommended that the DMA interrupt
is serviced before the SCSI interrupt, because a serious DMA
interrupt condition could influence how the SCSI interrupt is acted
upon.
6. When using polled interrupts go back to step 1 before leaving the
interrupt service routine in case any stacked interrupts moved in
when the first interrupt was cleared. When using hardware interrupts,
the INTA/ (or INTB/) pin is asserted again if there are any stacked
interrupts. This should cause the system to re-enter the interrupt
service routine.
2.2.17 Interrupt Routing
This section documents the recommended approach to RAID ready
interrupt routing for the SYM53C896. In order to be compatible with AMI
RAID upgrade products and the SYM53C896, the following requirements
must be met:
•
When a RAID upgrade card is installed in the upgrade slot, interrupts
from the motherboard SCSI controller(s) assigned to the RAID
upgrade card must be routed to INTC/ and INTD/ of the upgrade slot
and isolated from the motherboard interrupt controller. The system
processor must not see interrupts from the SCSI controllers that are
to be serviced by the RAID upgrade card. An upgrade slot is one that
is connected to the interrupt routing logic for motherboard SCSI
device(s). When a PCI RAID upgrade board is installed into the
system, it would be plugged into this slot if it is to control
motherboard SCSI device(s).
2-48
Functional Description
•
•
The TDI pin of the upgrade slot must be connected to the INT_DIR/
pin of the SYM53C896.
When a RAID upgrade card is not installed, interrupts from a SCSI
core must not be presented to the system’s interrupt controller using
multiple interrupt inputs.
Figure 2.8 shows an example configuration. In this example the
SYM53C896 Dual Channel Ultra2 SCSI Controller contains the interrupt
routing logic.
The SYM53C896 supports four different interrupt routing modes.
Additional information for these modes may be found in register 0x4D,
SCSI Test One (STEST1) description in Chapter 4, “Registers”. Each SCSI
core within the chip may be configured independently. The interrupt
routing mode is selected using bits [1:0] in the STEST1 register within
each core. Mode 0 is the default mode and is compatible with AMI RAID
upgrade products.
If the implementation shown in Figure 2.8 is used, INTC/ and INTD/ of
the PCI RAID upgrade slot cannot be used when a non-RAID upgrade
card is installed in the slot. If this restriction is not acceptable, additional
buffer logic must be implemented on the motherboard. As long as the
interrupt routing requirements stated above are satisfied, a motherboard
designer could implement this design with external logic.
SCSI Functional Description
2-49
Figure 2.8 Interrupt Routing Hardware Using the SYM53C896
+ 5 V
PCI RAID UPGRADE SLOT
10 K
+ 5 V
TDI
A4
PCI RAID
Upgrade
Slot INTA/
SYM53C896
2.7 K
INTA/
A6
+ 5 V
INTC/
ALT_INTA/
A7
SCSI Core
I
PCI RAID
Upgrade
Slot INTB/
2.7 K
INTB/
INTD/
INTA/
B7
B8
ALT_INTB/
INTB/
SCSI Core
II
MB SCSI INTA/
MB SCSI INTB/
These interrupt lines are
connected to the other PCI
slot interrupt lines as
determined by the
motherboard interrupt
routing scheme.
There can only be one entity controlling a motherboard SCSI core or
conflicts will occur. Typically a SCSI core will be controlled by the SCSI
BIOS and an operating system driver. When a SCSI core is allocated to
a RAID adapter, however, a mechanism must be implemented to prevent
the SCSI BIOS and operating system driver from trying to access the
SCSI core. The motherboard designer has several options to choose
from for doing this.
The first option is to have the SCSI core load its PCI Subsystem ID using
a serial EPROM on power-up. If bit 15 in this ID is set, the LSI Logic
Symbios BIOS and operating system drivers will ignore the chip. This
makes it possible to control the assignment of the motherboard SCSI
cores using a configuration utility.
The second option is to provide motherboard and system BIOS support
for NVS. The SCSI core may then be enabled or disabled using the SCSI
BIOS configuration utility. Not all versions of the Symbios drivers support
this capability.
2-50
Functional Description
The third option is to have the system BIOS not report the existence of
the SCSI controller chips when the SCSI BIOS and operating systems
make PCI BIOS calls. This approach requires modifications to the
system BIOS and assumes the operating system uses PCI BIOS calls
when searching for PCI devices.
2.2.18 Chained Block Moves
Since the SYM53C896 has the capability to transfer 16-bit wide SCSI
data, a unique situation occurs when dealing with odd bytes. The
Chained Move (CHMOV) SCRIPTS instruction along with the Wide SCSI
Send (WSS) and Wide SCSI Receive (WSR) bits in the SCSI Control Two
(SCNTL2) register are used to facilitate these situations. The Chained
Block Move instruction is illustrated in Figure 2.9.
2.2.18.1 Wide SCSI Send Bit
The WSS bit is set whenever the SCSI controller is sending data
(Data-Out for the initiator or Data-In for the target) and the controller
detects a partial transfer at the end of a chained Block Move SCRIPTS
instruction (this flag is not set if a normal Block Move instruction is used).
Under this condition, the SCSI controller does not send the low-order
byte of the last partial memory transfer across the SCSI bus. Instead, the
low-order byte is temporarily stored in the lower byte of the SCSI Output
Data Latch (SODL) register and the WSS flag is set. The hardware uses
the WSS flag to determine what behavior must occur at the start of the
next data send transfer. When the WSS flag is set at the start of the next
transfer, the first byte (the high-order byte) of the next data send transfer
is “married” with the stored low-order byte in the SODL register; and the
two bytes are sent out across the bus, regardless of the type of Block
Move instruction (normal or chained). The flag is automatically cleared
when the “married” word is sent. The flag is alternately cleared through
SCRIPTS or by the microprocessor. Also, the microprocessor or
SCRIPTS can use this bit for error detection and recovery purposes.
2.2.18.2 Wide SCSI Receive Bit
The WSR bit is set whenever the SCSI controller is receiving data
(Data-In for the initiator or Data-Out for the target) and the controller
detects a partial transfer at the end of a block move or chained block
move SCRIPTS instruction. When WSR is set, the high-order byte of the
SCSI Functional Description
2-51
last SCSI bus transfer is not transferred to memory. Instead, the byte is
temporarily stored in the SCSI Wide Residue (SWIDE) register. The
hardware uses the WSR bit to determine what behavior must occur at
the start of the next data receive transfer. The bit is automatically cleared
at the start of the next data receive transfer. The bit can alternatively be
cleared by the microprocessor or through SCRIPTS. Also, the
microprocessor or SCRIPTS can use this bit for error detection and
recovery purposes.
2.2.18.3 SWIDE Register
This register is used to store data for partial byte data transfers. For
receive data, the SCSI Wide Residue (SWIDE) register holds the
high-order byte of a partial SCSI transfer which has not yet been
transferred to memory. This stored data may be a residue byte (and
therefore ignored) or it may be valid data that is transferred to memory
at the beginning of the next Block Move instruction.
2.2.18.4 SODL Register
For send data, the low-order byte of the SCSI Output Data Latch (SODL)
register holds the low-order byte of a partial memory transfer which has
not yet been transferred across the SCSI bus. This stored data is usually
“married” with the first byte of the next data send transfer, and both bytes
are sent across the SCSI bus at the start of the next data send block
move command.
2.2.18.5 Chained Block Move SCRIPTS Instruction
A chained Block Move SCRIPTS instruction is primarily used to transfer
consecutive data send or data receive blocks. Using the chained Block
Move instruction facilitates partial receive transfers and allows correct
partial send behavior without additional opcode overhead. Behavior of
the chained Block Move instruction varies slightly for sending and
receiving data.
For receive data (Data-In for the initiator or Data-Out for the target), a
chained Block Move instruction indicates that if a partial transfer occurred
at the end of the instruction, the WSR flag is set. The high-order byte of
the last SCSI transfer is stored in the SCSI Wide Residue (SWIDE)
register rather than transferred to memory. The contents of the SWIDE
register should be the first byte transferred to memory at the start of the
2-52
Functional Description
chained Block Move data stream. Since the byte count always represents
data transfers to/from memory (as opposed to the SCSI bus), the byte
transferred out of the SCSI Wide Residue (SWIDE) register is one of the
bytes in the byte count. If the WSR bit is cleared when a receive data
chained Block Move instruction is executed, the data transfer occurs
similar to that of the regular Block Move instruction. Whether the WSR
bit is set or cleared, when a normal block move instruction is executed,
the contents of the SWIDE register are ignored and the transfer takes
place normally. For “N” consecutive wide data receive Block Move
instructions, the 2nd through the Nth Block Move instructions should be
chained block moves.
For send data (Data-Out for the initiator or Data-In for the target), a
chained Block Move instruction indicates that if a partial transfer
terminates the chained block move instruction, the last low-order byte
(the partial memory transfer) should be stored in the lower byte of the
SCSI Output Data Latch (SODL) register and not sent across the SCSI
bus. Without the chained Block Move instruction, the last low-order byte
would be sent across the SCSI bus. The starting byte count represents
data bytes transferred from memory but not to the SCSI bus when a
partial transfer exists. For example, if the instruction is an Initiator
chained Block Move Data Out of five bytes (and WSS is not previously
set), five bytes are transferred out of memory to the SCSI controller, four
bytes are transferred from the SCSI controller across the SCSI bus, and
one byte is temporarily stored in the lower byte of the SODL register
waiting to be married with the first byte of the next Block Move
instruction. Regardless of whether a chained Block Move or normal Block
Move instruction is used, if the WSS bit is set at the start of a data send
command, the first byte of the data send command is assumed to be the
high-order byte and is “married” with the low-order byte stored in the
lower byte of the SODL register before the two bytes are sent across the
SCSI bus. For “N” consecutive wide data send Block Move commands,
th
the first through the (N − 1) Block Move instructions should be Chained
Block Moves.
SCSI Functional Description
2-53
Figure 2.9 Block Move and Chained Block Move Instructions
Host Memory
SCSI Bus
0x04 0x03
0x06 0x05
0x03 0x02 0x01 0x00 00
0x07 0x06 0x05 0x04 04
0x0B 0x0A 0x09 0x08 08
0x0F 0x0E 0x0D 0x0C 0C
0x13 0x12 0x11 0x10 10
0x09 0x07
0x0B 0x0A
0x0D 0x0C
32 Bits
16 Bits
CHMOV 5, 3 when Data_Out
Moves five bytes from address 0x03 in the host memory to the SCSI bus.
Bytes 0x03, 0x04, 0x05, and 0x06 are moved and byte 0x07 remains in
the low-order byte of the SCSI Output Data Latch (SODL) register and is
combined with the first byte of the following MOVE instruction.
Move 5, 9 when Data_Out
Moves five bytes from address 0x09 in the host memory to the SCSI bus.
2-54
Functional Description
2.3 Parallel ROM Interface
The SYM53C896 supports up to one megabyte of external memory in
binary increments from 16 Kbytes to allow the use of expansion ROM for
add-in PCI cards. Both functions of the device share the ROM interface.
This interface is designed for low speed operations such as downloading
instruction code from ROM. It is not intended for dynamic activities such
as executing instructions.
System requirements include the SYM53C896, two or three external
8-bit address holding registers (HCT273 or HCT374), and the
appropriate memory device. The 4.7 kΩ pull-up resistors on the MAD bus
require HC or HCT external components to be used. If in-system Flash
ROM updates are required, a 7406 (high voltage open collector inverter),
a MTD4P05, and several passive components are also needed. The
memory size and speed is determined by pull-up resistors on the
8-bit bidirectional memory bus at power-up. The SYM53C896 senses this
bus shortly after the release of the Reset signal and configures the
Expansion ROM Base Address register and the memory cycle state
machines for the appropriate conditions.
The external memory interface works with a variety of ROM sizes and
speeds. An example set of interface drawings is in Appendix B, “External
Memory Interface Diagram Examples”.
The SYM53C896 supports a variety of sizes and speeds of expansion
ROM, using pull-down resistors on the MAD[3:0] pins. The encoding of
pins MAD[3:1] allows the user to define how much external memory is
available to the SYM53C896. Table 2.7 shows the memory space
Parallel ROM Interface
2-55
associated with the possible values of MAD[3:1]. The MAD[3:1] pins are
fully described in Chapter 3, “Signal Descriptions”.
Table 2.7
Parallel ROM Support
MAD[3:1]
000
Available Memory Space
16 Kbytes
001
010
011
100
101
110
111
32 Kbytes
64 Kbytes
128 Kbytes
256 Kbytes
512 Kbytes
1024 Kbytes
no external memory present
To use one of the configurations mentioned above in a host adapter
board design, put 4.7 kΩ pull-up resistors on the MAD pins
corresponding to the available memory space. For example, to connect
to a 64 Kbytes external ROM, use a pull-up on MAD[2]. If the external
memory interface is not used, MAD[3:1] should be pulled high.
Note:
There are internal pull-downs on all of the MAD bus
signals.
The SYM53C896 allows the system to determine the size of the available
external memory using the Expansion ROM Base Address register in the
PCI configuration space. For more information on how this works, refer
to the PCI specification or the Expansion ROM Base Address register
description in Chapter 4, “Registers”.
MAD[0] is the slow ROM pin. When pulled up, it enables two extra clock
cycles of data access time to allow use of slower memory devices. The
external memory interface also supports updates to flash memory.
2-56
Functional Description
2.4 Serial EEPROM Interface
The SYM53C896 implements an interface that allows attachment of a
serial EEPROM device to the GPIO0 and GPIO1 pins for each SCSI
function. There are two modes of operation relating to the serial
EEPROM and the Subsystem ID and Subsystem Vendor ID registers for
each SCSI function. These modes are programmable through the
MAD[7] pin which is sampled at power-up or hard reset.
2.4.1 Default Download Mode
In this mode, MAD[7] is pulled down internally, GPIO0 is the serial data
signal (SDA) and GPIO1 is the serial clock signal (SCL). Certain data in
the serial EEPROM is automatically loaded into chip registers at
power-up or hard reset.
The format of the serial EEPROM data is defined in Table 2.8. If the
download is enabled and an EEPROM is not present, or the checksum
fails, the Subsystem ID and Subsystem Vendor ID registers read back all
zeros. At power-up or hard reset, only five bytes are loaded into the chip
from locations 0xFB through 0xFF.
The Subsystem ID and Subsystem Vendor ID registers are read only, in
accordance with the PCI specification, with a default value of all zeros if
the download fails.
Serial EEPROM Interface
2-57
Table 2.8
Mode A Serial EEPROM Data Format
Byte
Name
Description
0xFB
SVID(0)
Subsystem Vendor ID, LSB. This byte is loaded into the least significant
byte of the Subsystem Vendor ID register in the appropriate PCI
configuration space at chip power-up or hard reset.
0xFC
0xFD
0xFE
0xFF
SVID(1)
SID(0)
Subsystem Vendor ID, MSB. This byte is loaded into the most significant
byte of the Subsystem Vendor ID register in the appropriate PCI
configuration space at chip power-up or hard reset.
Subsystem ID, LSB. This byte is loaded into the least significant byte of
the Subsystem ID register in the appropriate PCI configuration space at
chip power-up or hard reset.
SID(1)
Subsystem ID, MSB. This byte is loaded into the most significant byte of
the Subsystem ID register in the appropriate PCI configuration space at
chip power-up or hard reset.
CKSUM
Checksum. This 8-bit checksum is formed by adding, bytewise, each
byte contained in locations 0x00–0x03 to the seed value 0x55, and then
taking the 2s complement of the result.
0x100–EOM UD
User Data.
2.4.2 No Download Mode
When MAD[7] is pulled up through an external resistor, the automatic
download is disabled and no data is automatically loaded into chip
registers at power-up or hard reset. The Subsystem ID and Subsystem
Vendor ID registers are read only, per the PCI specification, with a default
value of 0x1000 and 0x1000 respectively.
2.5 Power Management
The SYM53C896 complies with the PCI Bus Power Management
Interface Specification, Revision 1.1. The PCI Function Power States D0,
D1, D2, and D3 are defined in that specification.
D0 is the maximum powered state, and D3 is the minimum powered
state. Power state D3 is further categorized as D3hot or D3cold. A
function that is powered off is said to be in the D3cold power state.
2-58
Functional Description
The SYM53C896 power states are independently controlled through two
power state bits that are located in the PCI Configuration Space
Power Management Control/Status (PMCSR) register 0x44–0x45.
Table 2.9
Power States
Configuration
Register 0x44
Bits [1:0]
Power State Function
00
01
10
11
D0
D1
D2
D3
Maximum Power
Disables SCSI clock
Coma Mode
Minimum Power
Although the PCI Bus Power Management Interface Specification does
not allow power state transitions D2 to D1, D3 to D2, or D3 to D1, the
SYM53C896 hardware places no restriction on transitions between
power states.
The PCI Function Power States D0, D1, D2, and D3 are described below
in conjunction with each SCSI function. Power state actions are separate
for each function.
As the device transitions from one power level to a lower one, the
attributes that occur from the higher power state level are carried over
into the lower power state level. For example, D1 disables the SCSI CLK.
Therefore, D2 will include this attribute as well as the attributes defined
in the Power State D2 section. The PCI Function Power States - D0, D1,
D2, and D3 are described below in conjunction with each SCSI function.
Power state actions are separate for each function.
2.5.1 Power State D0
Power state D0 is the maximum power state and is the power-up default
state for each function. The SYM53C896 is fully functional in this state.
2.5.2 Power State D1
Power state D1 is a lower power state than D0. A function in this state
places the SYM53C896 core in the snooze mode and disables the SCSI
Power Management
2-59
CLK. In the snooze mode, a SCSI reset does not generate an IRQ/
signal.
2.5.3 Power State D2
Power state D2 is a lower power state than D1. A function in this state
places the SYM53C896 core in the coma mode. The following PCI
Configuration Space Command register enable bits are suppressed:
•
•
•
•
•
I/O Space Enable
Memory Space Enable
Bus Mastering Enable
SERR/Enable
Enable Parity Error Response
Thus, the function's memory and I/O spaces cannot be accessed, and
the function cannot be a PCI bus master. Furthermore, SCSI and DMA
interrupts are disabled when the function is in power state D2. If the
function is changed from power state D2 to power state D1 or D0, the
previous values of the PCI Command register are restored. Also, any
pending interrupts before the function entered power state D2 are
asserted.
2.5.4 Power State D3
Power state D3 is the minimum power state, which includes settings
called D3hot and D3cold. D3hot allows the device to transition to D0
using software. The SYM53C896 is considered to be in power state
D3cold when power is removed from the device. D3cold can transition to
D0 by applying V
and resetting the device.
CC
Power state D3 is a lower power level than power state D2. A function in
this state places the SYM53C896 core in the coma mode. Furthermore,
the function's soft reset is continually asserted while in power state D3,
which clears all pending interrupts and 3-states the SCSI bus. In
addition, the function's PCI Command register is cleared. If both of the
SYM53C896 functions are placed in power state D3, the Clock
Quadrupler is disabled, which results in additional power savings.
2-60
Functional Description
Chapter 3
Signal Descriptions
This chapter presents the SYM53C896 pin configuration and signal
definitions using tables and illustrations. Figure 3.1 is the functional signal
grouping. The signal descriptions begin with Table 3.2. The signal
descriptions are organized into functional groups:
•
•
•
•
•
•
•
Section 3.1, “Internal Pull-ups on SYM53C896 Signals”
Section 3.2, “PCI Bus Interface Signals”
Section 3.3, “SCSI Bus Interface Signals”
Section 3.4, “ROM Flash and Memory Interface Signals”
Section 3.5, “Test Interface Signals”
Section 3.6, “Power and Ground Signals”
Section 3.7, “MAD Bus Programming”
The PCI Interface signals are divided into the following functional groups:
System Signals, Address and Data Signals, Interface Control Signals,
Arbitration Signals, Error Reporting Signals, Interrupt Signals, SCSI
Function A GPIO Signals, and SCSI Function B GPIO Signals.
The SCSI Bus Interface signals are divided into SCSI Function A Signals,
and SCSI Function B Signals groups.
A slash (/) at the end of a signal name indicates that the active state
occurs when the signal is at a low voltage. When the slash is absent, the
signal is active at a high voltage.
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
3-1
Figure 3.1 SYM53C896 Functional Signal Grouping
SYM53C896
CLK
RST/
SCLK
System
AD[63:0]
C_BE[7:0]
PAR
Address
and
Data
A_SD[15:0]/
A_SDP[1:0]/
A_DIFFSENS
PAR64
ACK64/
REQ64/
FRAME/
TRDY/
IRDY/
STOP/
A_SC_D/
A_SI_O/
SCSI
Function
A
A_SMSG/
A_SREQ/
A_SREQ2/
A_SACK/
A_SACK2/
A_SBSY/
A_SATN/
A_SRST/
A_SSEL/
Interface
Control
A_SCTRL/
DEVSEL/
IDSEL
SCSI
Bus
Interface
REQ/
GNT/
Arbitration
PCI
Bus
Interface
Error
Reporting
PERR/
SERR/
B_SD[15:0]/
B_SDP[1:0]/
B_DIFFSENS
INTA/
INTB/
Interrupt
ALT_INTA/
ALT_INTB/
INT_DIR
B_SC_D/
B_SI_O/
B_SMSG/
B_SREQ/
B_SREQ2/
SCSI
Function
B
A_GPIO0_FETCH/
A_GPIO1_MASTER/
A_GPIO2
A_GPIO3
A_GPIO4
SCSI
Function
A
B_SACK/
B_SACK2/
B_SBSY/
B_SATN/
B_SRST/
B_SSEL/
B_SCTRL/
GPIO
B_GPIO0_FETCH/
B_GPIO1_MASTER/
B_GPIO2
B_GPIO3
B_GPIO4
SCSI
Function
B
GPIO
TEST_RST/
TEST_HSC
MOE/_TESTOUT
TCK
Test
Interface
MWE/
MCE/
MOE/_TESTOUT
MAS0/
MAS1/
ROM
FLASH
and
Memory
Interface
TMS
TDI
TDO
MAD[7:0]
3-2
Signal Descriptions
There are five signal type definitions:
I
Input, a standard input-only signal.
O
Output, a standard output driver (typically a Totem Pole Output).
Input and output (bidirectional).
I/O
T/S
3-state, a bidirectional, 3-state input/output signal.
S/T/S Sustained 3-state, an active low 3-state signal owned and driven by one
and only one agent at a time.
3-3
3.1 Internal Pull-ups on SYM53C896 Signals
Several SYM53C896 signals use internal pull-ups and pull-downs. The
following table describes the conditions that enable these pull-ups and
pull-downs.
Table 3.1
Pin Name
SYM53C896 Internal Pull-ups and Pull-downs
Pull-up
current
Conditions for pull-up
INTA/, INTB/, ALT_INTA/,
ALT_INTB/
25 µA
Pull-up enabled when the and-tree mode is
enabled by driving TEST_RST/ low or when the
IRQ mode bit (bit 3 of DCNTL, 0X3B) is cleared.1
INT_DIR, TCK, TDI,
TEST_RST/, TMS
25 µA
Pulled up internally.
AD[63:32], C_BE[7:4], PAR64
GPIO[4:0]
25 µA
−25 µA
−25 µA
−25 µA
Pulled up internally if not used.
Pulled down internally when configured as inputs.
Pulled down internally.
MAD[7:0]
TDO, TEST_HSC
Pulled down internally.
1. When bit 3 of DMA Control (DCNTL) is set, the pad becomes a totem pole output pad and will
drive both high and low.
3-4
Signal Descriptions
3.2 PCI Bus Interface Signals
The PCI Bus Interface Signals section contains tables describing the
signals for the following signal groups: System Signals, Address and Data
Signals, Interface Control Signals, Arbitration Signals, Error Reporting
Signals, Interrupt Signals, SCSI Function A GPIO Signals, and SCSI
Function B GPIO Signals.
3.2.1 System Signals
This section describes the signals for the System Signals Group.
System Signals
Table 3.2
Name
Bump Type Strength Description
CLK
H3
I
N/A
Clock provides timing for all transactions on the PCI bus and
is an input to every PCI device. All other PCI signals are
sampled on the rising edge of CLK, and other timing
parameters are defined with respect to this edge. Clock can
optionally serve as the SCSI core clock, but this may effect fast
SCSI-2 (or faster) transfer rates.
RST/
G1
I
N/A
Reset forces the PCI sequencer of each device to a known
state. All T/S and S/T/S signals are forced to a high impedance
state, and all internal logic is reset. The RST/ input is
synchronized internally to the rising edge of CLK. The CLK
input must be active while RST/ is active to properly reset the
device.
PCI Bus Interface Signals
3-5
3.2.2 Address and Data Signals
This section describes the signals for the Address and Data Signals
group.
Table 3.3
Address and Data Signals
Name
Bump
Type Strength Description
AD[63:0]
Y5, AB5, AC5, AA6, T/S
Y6, AB6, AC6, AA7,
AB7, AC7, AA8, Y8,
AB8, AC8, AA9, Y9,
AB9, AC9, AA10,
Y11, AB10, AC10,
AA11, AC11, AB11,
AC12, AA12, AB12,
AB13, AC13, AA13,
AC14, H1, J3, J4,
J2, J1, K3, L4, K2,
L1, L2, M1, M3, M2,
N2, N1, N3, T4, T3,
U1-U3, V1, V2, V4,
W1, W2, W4, W3,
Y1, Y2, AA1, Y3.
16 mA
PCI
Physical dword Address and Data are
multiplexed on the same PCI pins. A bus
transaction consists of an address phase
followed by one or more data phases.
During the first clock of a transaction,
AD[63:0] contain a 64-bit physical byte
address. If the command is a DAC,
implying a 64-bit address, AD[31:0] will
contain the upper 32 bits of the address
during the second clock of the
transaction. During subsequent clocks,
AD[63:0] contain data. PCI supports both
read and write bursts. AD[7:0] define the
least significant byte, and AD[63:56]
define the most significant byte.
C_BE[7:0]/
AA4, AC3, AB4,
AC4, K1, P1, T2, V3.
T/S
16 mA
PCI
Bus Command and Byte Enables are
multiplexed on the same PCI pins.
During the address phase of a
transaction, C_BE[3:0]/ define the bus
command. If the transaction is a DAC,
C_BE[3:0]/ contain the DAC command
and C_BE[7:4]/ define the bus command.
C_BE[3:0]/ define the bus command
during the second clock of the
transaction. During the data phase,
C_BE[7:0]/ are used as byte enables.
The byte enables determine which byte
lanes carry meaningful data. C_BE[0]/
applies to byte 0, and C_BE[7]/ to byte 7.
PAR
T1
T/S
16 mA
PCI
Parity is the even parity bit that protects
the AD[31:0] and C_BE[3:0]/ lines.
During the address phase, both the
address and command bits are covered.
During data phase, both data and byte
enables are covered.
3-6
Signal Descriptions
Table 3.3
Address and Data Signals (Cont.)
Name
Bump
Type Strength Description
PAR64
AA5
T/S
16 mA
PCI
Parity64 is the even parity bit that
protects the AD[63:32] and C_BE[7:4]/
lines. During address phase, both the
address and command bits are covered.
During data phase, both data and byte
enables are covered.
3.2.3 Interface Control Signals
This section describes the signals for the Interface Control Signals group.
Interface Control Signals
Table 3.4
Name
Bump
Type Strength Description
ACK64/
AB1
S/T/S 16 mA
PCI
Acknowledge 64-bit transfer is driven by the current bus
target to indicate its ability to transfer 64-bit data.
REQ64/
FRAME/
AA2
P2
S/T/S 16 mA
PCI
Request 64-bit transfer is driven by the current bus master
to indicate a request to transfer 64-bit data.
S/T/S 16 mA
PCI
Cycle Frame is driven by the current master to indicate the
beginning and duration of an access. FRAME/ is asserted
to indicate that a bus transaction is beginning. While
FRAME/ is deasserted, either the transaction is in the final
data phase or the bus is idle.
TRDY/
P3
S/T/S 16 mA
PCI
Target Ready indicates the target agent’s (selected
device’s) ability to complete the current data phase of the
transaction. TRDY/ is used with IRDY/. A data phase is
completed on any clock when used with IRDY/. A data
phase is completed on any clock when both TRDY/ and
IRDY/ are sampled asserted. During a read, TRDY/
indicates that valid data is present on AD[31:0]. During a
write, it indicates that the target is prepared to accept data.
Wait cycles are inserted until both IRDY/ and TRDY/ are
asserted together.
IRDY/
N4
S/T/S 16 mA
PCI
Initiator Ready indicates the initiating agent’s (bus
master’s) ability to complete the current data phase of the
transaction. IRDY/ is used with TRDY/. A data phase is
completed on any clock when both IRDY/ and TRDY/ are
sampled asserted. During a write, IRDY/ indicates that valid
data is present on AD[31:0]. During a read, it indicates that
the master is prepared to accept data. Wait cycles are
inserted until both IRDY/ and TRDY/ are asserted together.
PCI Bus Interface Signals
3-7
Table 3.4
Interface Control Signals (Cont.)
Name
Bump
Type Strength Description
STOP/
R2
S/T/S 16 mA
PCI
Stop indicates that the selected target is requesting the
master to stop the current transaction.
DEVSEL/ R1
S/T/S 16 mA
PCI
Device Select indicates that the driving device has
decoded its address as the target of the current access. As
an input, it indicates to a master whether any device on the
bus has been selected.
IDSEL
L3
I
N/A
Initialization Device Select is used as a chip select in
place of the upper 24 address lines during configuration
read and write transactions.
3.2.4 Arbitration Signals
This section describes the signals for the Arbitration Signals group.
Arbitration Signals
Table 3.5
Name
Bump
Type Strength Description
REQ/
H2
O
16 mA
PCI
Request indicates to the system arbiter that this agent
desires use of the PCI bus. This is a point-to-point signal.
Both SCSI functions share the REQ/ signal.
GNT/
H4
I
N/A
Grant indicates to the agent that access to the PCI bus has
been granted. This is a point-to-point signal. Both SCSI
functions share the GNT/ signal.
3-8
Signal Descriptions
3.2.5 Error Reporting Signals
This section describes the signals for the Error Reporting Signals group.
Error Reporting Signals
Table 3.6
Name
Bump Type Strength Description
PERR/
R4
R3
S/T/S 16 mA
PCI
Parity Error may be pulsed active by an agent that detects
a data parity error. PERR/ can be used by any agent to
signal data corruption. However, on detection of a PERR/
pulse, the central resource may generate a nonmaskable
interrupt to the host CPU, which often implies the system is
unable to continue operation once error processing is
complete.
SERR/
O
16 mA
PCI
System Error is an open drain output used to report
address parity errors as well as critical errors other than
parity.
PCI Bus Interface Signals
3-9
3.2.6 Interrupt Signals
This section describes the Interrupt Signals group.
Interrupt Signals
Table 3.7
Name1
Bump Type Strength Description
INTA/
F4
O
16 mA
PCI
Interrupt Function A. This signal, when asserted low,
indicates an interrupting condition in SCSI Function A and
that service is required from the host CPU. The output drive
of this pin is open drain. If the SCSI Function B interrupt is
rerouted at power-up using the INTA/ enable sense resistor
(pull-up on MAD[4]), this signal indicates that an interrupting
condition has occurred in either the SCSI Function A or
SCSI Function B. This interrupt pin is disabled if INT_DIR is
driven low.
INTB/
F2
O
16 mA
PCI
Interrupt Function B. This signal, when asserted low,
indicates an interrupting condition has occurred in the SCSI
Function B and that service is required from the host CPU.
The output drive of this pin is open drain. This interrupt can
be rerouted to INTA/ at power-up using the INTA/ enable
sense resistor (pull-up on MAD[4]). This causes the
SYM53C896 to program the SCSI Function B PCI Interrupt
Pin register (0x3D) to 0x01. This interrupt pin is disabled if
INT_DIR is driven low.
ALT_INTA/ F1
ALT_INTB/ G3
O
O
I
16 mA
PCI
Alt Interrupt Function A. When asserted low, it indicates
an interrupting condition has occurred in SCSI Function A.
The output drive of this pin is open drain. If the SCSI
Function B interrupt was rerouted at power-up using the
INTA/ enable sense resistor (pull-up on MAD[4]), this signal
indicates that an interrupting condition has occurred in
either the SCSI Function A or SCSI Function B.
16 mA
PCI
Alt Interrupt Function B. When asserted low, indicates an
interrupting condition has occurred in SCSI Function B. The
output drive of this pin is open drain. This interrupt can be
rerouted to INTA/ at power-up using the INTA/ enable sense
resistor (pull-up on MAD[4]). This will cause the
SYM53C896 to program the Function B PCI Interrupt Pin
register (0x3D) to 0x01.
INT_DIR
G2
N/A
Interrupt Direction. This input signal indicates whether
internally generated interrupts will be presented on INTA/
and INTB/. If INT_DIR is high, internal interrupts will be
generated on both the INTx/ pins and the ALT_INTx pin. If
INT_DIR is low, the internal interrupts will be generated only
on the ALT_INTx/ pin. This pin has a static pull-up.
1. See Register 0x4D, SCSI Test One (STEST1) in Chapter 4, “Registers” for additional information on
these signals.
3-10
Signal Descriptions
3.2.7 SCSI Function A GPIO Signals
This section describes the signals for the SCSI Function A GPIO group.
SCSI Function A GPIO Signals
Table 3.8
Name
Bump
Type Strength Description
I/O 8 mA
A_GPIO0_ AB16
FETCH/
SCSI Function A General Purpose I/O pin 0. This pin
is programmable at power-up through the MAD[7] pin to
serve as the data signal for the serial EEPROM interface.
When GPIO_0 is not in the process of downloading
EEPROM data it can be used to drive a SCSI Activity
LED if bit 5 in the General Purpose Pin Control (GPCNTL)
register is set. Or, it can be used to indicate that the next
bus request will be an opcode fetch if bit 6 in the
GPCNTL register is set.
A_GPIO1_ Y16
MASTER/
I/O
8 mA
SCSI Function A General Purpose I/O pin 1. This pin
is programmable at power-up through the MAD[7] pin to
serve as the clock signal for the serial EEPROM interface.
When General Purpose Pin Control (GPCNTL) bit 7 is set,
this pin drives low when the SYM53C896 is bus master.
A_GPIO2
A_GPIO3
A_GPIO4
AA16
AC17
AB17
I/O
I/O
I/O
8 mA
8 mA
8 mA
SCSI Function A General Purpose I/O pin 2. This pin
powers up as an input.
SCSI Function A General Purpose I/O pin 3. This pin
powers up as an input.
SCSI Function A General Purpose I/O pin 4. This pin
powers up as an output.
PCI Bus Interface Signals
3-11
3.2.8 SCSI Function B GPIO Signals
This section describes the signals for the SCSI Function B GPIO group.
SCSI Function B GPIO Signals
Table 3.9
Name
Bump
Type Strength Description
I/O 8 mA
B_GPIO0_
FETCH/
AA14
SCSI Function B General Purpose I/O pin 0. This pin
is programmable at power-up through the MAD[7] pin
to serve as the data signal for the serial EEPROM
interface. When GPIO_0 is not in the process of
downloading EEPROM data it can be used to drive a
SCSI Activity LED if bit 5 in the General Purpose Pin
Control (GPCNTL) register is set. Or, it can be used to
indicate that the next bus request will be an opcode
fetch if bit 6 in the GPCNTL register is set.
B_GPIO1_
MASTER/
AC15
I/O
8 mA
SCSI Function B General Purpose I/O pin 1. This pin
is programmable at power-up through the MAD[7] pin
to serve as the clock signal for the serial EEPROM
interface. When General Purpose Pin Control (GPCNTL)
bit 7 is set, this pin is driven low when the SYM53C896
is bus master.
B_GPIO2
B_GPIO3
B_GPIO4
AB15
AA15
AC16
I/O
I/O
I/O
8 mA
8 mA
8 mA
SCSI Function B General Purpose I/O pin 2. This pin
powers up as an input.
SCSI Function B General Purpose I/O pin 3. This pin
powers up as an input.
SCSI Function B General Purpose I/O pin 4. This pin
powers up as an output.
3-12
Signal Descriptions
3.3 SCSI Bus Interface Signals
The SCSI Bus Interface Signals section contains tables describing the
signals for the following signal groups: SCSI Bus Interface Signals, SCSI
Function A Signals, and SCSI Function B Signals. SCSI Function A signals
and SCSI Function B signals each have a subgroup: SCSI Function
A_SCTRL Signals signals and SCSI Function B_SCRTL Signals signals.
The following table contains signals that are common to both SCSI
buses.
Table 3.10 SCSI Bus Interface Signals
Name
Bump
Type Strength Description
N/A
SCLK
A21
I
SCSI Clock is used to derive all SCSI-related timings. The
speed of this clock is determined by the application’s
requirements. In some applications, SCLK may be sourced
internally from the PCI bus clock (CLK). If SCLK is internally
sourced, then the SCLK pin should be tied low. For Ultra2
SCSI operations, the clock supplied to SCLK must be 40
MHz. The clock frequency will be quadrupled to create the
160 MHz clock required internally by both SCSI functions.
3.3.1 SCSI Function A Signals
This section describes the signals for the SCSI Function A Signals group.
It is divided into two tables: SCSI Function A Signals and SCSI Function
A_SCTRL Signals.
SCSI Bus Interface Signals
3-13
Table 3.11 SCSI Function A Signals
Name
Bump
Type Strength Description
A_SD[15:0]−
B5, C5, B4, C4,
D19, A19, D18,
A18, D11, A9, D9,
A8, D8, A7, C7, B6.
I/O
48 mA
SCSI
SCSI Function A Data and Parity.
LVD Mode: Negative half of LVD Link pair
for SCSI data and parity lines.
A_SD[15:0]− are the 16-bit SCSI data bus,
and A_SDP[1:0]− are the SCSI data parity
lines.
A_SDP[1:0]−
C6, A10.
SE Mode: A_SD[15:0]− are the 16-bit SCSI
data bus, and A_SDP[1:0]− are the SCSI
data parity lines.
HVD Mode: A_SD[15:0]− and A_SDP[1:0]−
are the SCSI data bus.
A_SD[15:0]+
A_SDP[1:0]+
A5, D5, A4, A3,
C19, B19, C18,
B18, B10, C10, B9,
C9, B8, C8, B7, A6.
I/O
48 mA
SCSI
SCSI Function A Data and Parity.
LVD Mode: Positive half of LVD Link pair
for SCSI data lines. A_SD[15:0]+ are the
16-bit data bus, and A_SDP[1:0]+ are the
SCSI data parity lines.
D6, C11.
SE Mode: A_SD[15:0]+ and A_SDP[1:0]+
are at 0 V.
HVD mode: A_SD[15:0]+ and A_SDP+ are
driver directional control for SCSI data
lines.
A_DIFFSENS A20
I
N/A
SCSI Function A Differential Sense pin
detects the present mode of the SCSI bus
when connected to the DIFFSENS signal
on the physical SCSI bus.
LVD Mode: When a voltage between 0.7 V
and 1.9 V is present on this pin, the SCSI
Function A will operate in the LVD mode.
SE Mode: When this pin is driven low
(below 0.5 V) indicating SE bus operation,
the SCSI Function A will operate in the SE
mode.
HVD Mode: When this pin is detected high
(above 2.4 V) indicating a HVD bus, the
SCSI Function A will 3-state its SCSI
drivers. Set the DIF bit in SCSI Test Two
(STEST2) to enable HVD drivers.
3-14
Signal Descriptions
3.3.1.1 A_SCTRL Signals
Table 3.12 SCSI Function A_SCTRL Signals
Name
Bump
Type Strength Description
SCSI Function A Control includes the following signals:
A_SC_D−
A_SC_D+
C15
A16
I/O
48 mA
SCSI
SCSI phase line, command/data.
SCSI phase line, input/output.
SCSI phase line, message.
A_SI_O−
A_SI_O+
B17
C17
A_SMSG−
A_SMSG+
C14
A15
A_SREQ−
A_SREQ+
C16
A17
Data handshake line from target device.
A_SREQ2− B16
A_SREQ2+ D16
Data handshake line from target device. Duplicate of
A_SREQ− enabled by pulling MAD[5] HIGH at reset.
A_SACK−
A_SACK+
C13
A14
Data handshake signal from the initiator device.
A_SACK2−
A_SACK2+
B13
A13
Data handshake signal from the initiator device. Duplicate
of B_SACK− and B_SACK+ enabled by pulling MAD[5]
HIGH at reset.
A_SBSY−
A_SBSY+
C12
A12
SCSI bus arbitration signal, busy.
A_SATN−
A_SATN+
B11
B12
SCSI Attention, the initiator is requesting a message out
phase.
A_SRST−
A_SRST+
B14
D13
SCSI bus reset.
A_SSEL−
A_SSEL+
B15
D15
SCSI bus arbitration signal, select device.
For all A_SCTRL Signals:
LVD Mode: Negative and positive halves of LVD Link
signal pairs shown for SCSI Function A Control.
SE Mode: SCSI Function A Control signals shown.
+ signals are at 0 V.
HVD Mode: SCSI Function A Control signals shown.
+ signals become direction control.
SCSI Bus Interface Signals
3-15
3.3.2 SCSI Function B Signals
This section describes the signals for the SCSI Function B Signals group.
It is divided into two tables: SCSI Function B Signals and SCSI Function
B_SCRTL Signals.
Table 3.13 SCSI Function B Signals
Name
Bump
Type Strength Description
B_SD[15:0]−
F21, E22, E21, D22, I/O
Y22, W21, W22, V21,
K23, L20, J23, J20,
48 mA
SCSI
SCSI Function B Data and Parity.
LVD Mode: Negative half of LVD Link
pair for SCSI data and parity lines.
B_SD[15:0]− are the 16-bit SCSI data
bus, and B_SDP[1:0]− are the SCSI
data parity lines.
H23, H20, G23, G21.
B_SDP[1:0]−
F22, L23.
SE Mode: B_SD[15:0]− are the 16-bit
SCSI data bus, and B_SDP[1:0]− are
the SCSI data parity lines.
HVD Mode: B_SD[15:0]− and
B_SDP[1:0]− are the SCSI data bus.
B_SD[15:0]+
B_SDP[1:0]+
F20, E23, E20, D23, I/O
AA23, Y23, W20,
W23, L21, K22, K21,
J22, J21, H22, H21,
G22.
48 mA
SCSI
SCSI Function B Data and Parity.
LVD Mode: Positive half of LVD Link
pair for SCSI data lines. B_SD[15:0]+
are the 16-bit data bus, and
B_SDP[1:0]+ are the SCSI data parity
lines.
F23, L22.
SE Mode: B_SD[15:0]+ and
B_SDP[1:0]+ are at 0 V.
HVD mode: B_SD[15:0]+ and
B_SDP[1:0]+ are driver directional
control for SCSI data lines.
3-16
Signal Descriptions
Table 3.13 SCSI Function B Signals (Cont.)
Name
Bump
Type Strength Description
B_DIFFSENS
Y21
I
N/A
SCSI Function B Differential Sense
pin detects the present mode of the
SCSI bus when connected to the
DIFFSENS signal on the physical SCSI
bus.
LVD Mode: When a voltage between
0.7 V and 1.9 V is present on this pin,
the SCSI Function B will operate in the
LVD mode.
SE Mode: When this pin is driven low
(below 0.5 V) indicating SE bus
operation, the SCSI Function B will
operate in the SE mode.
HVD Mode: When this pin is detected
HIGH (above 2.4 V) indicating a HVD
bus, the SCSI Function B will 3-state its
SCSI drivers. Set the DIF bit in STEST2
to enable HVD drivers.
SCSI Bus Interface Signals
3-17
Table 3.14 SCSI Function B_SCRTL Signals
Name
Bump Type Strength Description
SCSI Function B Control includes the following signals:
B_SC_D−
B_SD_D+
T20
T21
I/O
48 mA
SCSI
SCSI phase line, command/data.
SCSI phase line, input/output.
SCSI phase line, message.
B_SI_O−
B_SI_O+
V22
V20
B_SMSG−
B_SMSG+
R20
R21
B_SREQ−
B_SREQ+
U21
V23
Data handshake line from target device.
B_SREQ2−
B_SREQ2+
U23
U22
Data handshake line from target device. Duplicate of
B_SREQ− enabled by pulling MAD[6] HIGH at reset.
B_SACK−
B_SACK+
N20
P21
Data handshake signal from the initiator device.
B_SACK2−
B_SACK2+
P23
P22
Data handshake signal from the initiator device.
Duplicate of B_SACK− and B_SACK+ enabled by
pulling MAD[6] HIGH at reset.
B_SBSY−
B_SBSY+
N23
N21
SCSI bus arbitration signal, busy.
B_SATN−
B_SATN+
M23
N22
SCSI Attention, the initiator is requesting a message
out phase.
B_SRST−
B_SRST+
R23
R22
SCSI bus reset.
B_SSEL−
B_SSEL+
T23
T22
SCSI bus arbitration signal, select device.
For all B_SCRTL Signals:
LVD Mode: Negative and positive halves of LVD Link
signal pairs shown for SCSI Function B Control.
SE Mode: SCSI Function B Control signals shown.
+ signals are at 0 V.
HVD Mode: SCSI Function B Control signals shown.
+ signals become direction control.
3-18
Signal Descriptions
3.4 ROM Flash and Memory Interface Signals
This section describes the signals for the ROM Flash and Memory
Interface Signals group.
Table 3.15 ROM Flash and Memory Interface Signals
Name
Bump
Type Strength Description
MWE/
AC19
O
O
O
4 mA
4 mA
4 mA
Memory Write Enable. This pin is used as a write
enable signal to an external flash memory.
MCE/
AA18
Y18
Memory Chip Enable. This pin is used as a chip enable
signal to an external EPROM or flash memory device.
MOE/_
TESTOUT
Memory Output Enable. This pin is used as an output
enable signal to an external EPROM or flash memory
during read operations. It is also used to test the
connectivity of the SYM53C896 signals in the “AND-
tree” test mode. The MOE/_TESTOUT pin is only driven
as the test out function when the ZMODE bit (Chip
Control 1 (CCNTL1), bit 7) is set.
MAS0/
MAS1/
AC18
AA17
O
O
4 mA
4 mA
4 mA
Memory Address Strobe 0. This pin is used to latch in
the least significant address byte (bits [7:0]) of an
external EPROM or flash memory. Since the
SYM53C896 moves addresses eight bits at a time, this
pin connects to the clock of an external bank of flip-flops
which are used to assemble up to a 20-bit address for
the external memory.
Memory Address Strobe 1. This pin is used to latch in
the most significant address byte (bits [15:8]) of an
external EPROM or flash memory. Since the
SYM53C896 moves addresses eight bits at a time, this
pin connects to the clock of an external bank of flip-flops
which assemble up to a 20-bit address for the external
memory.
MAD[7:0] Y19, AA19, I/O
Memory Address/Data Bus. This bus is used in
conjunction with the memory address strobe pins and
external address latches to assemble up to a 20-bit
address for an external EPROM or flash memory. This
bus will put out the least significant byte first and finish
with the most significant bits. It is also used to write data
to a flash memory or read data into the chip from
external EPROM/flash memory. These pins have static
pull-downs.
AC20,
AB20,
AA20,
AC22,
AB21,
AC23.
ROM Flash and Memory Interface Signals
3-19
3.5 Test Interface Signals
This section describes the signals for the Test Interface group. The table
is divided into Internal Test Signals and JTAG Signals.
Table 3.16 Test Interface Signals
Name
Bump
Type Strength Description
Internal Test Signals
TEST_HSC C23
I
N/A
Test Halt SCSI Clock. For LSI Logic test purposes
only. Pulled LOW internally. This signal can also cause
a full chip reset.
TEST_RST/ C1
I
N/A
Test Reset. For LSI Logic test purposes only. Pulled
HIGH internally.
MOE/_
TESTOUT
Y18
O
4 mA
Memory Output Enable. This pin is used as an
output enable signal to an external EPROM or flash
memory during read operations. It is also used to test
the connectivity of the SYM53C896 signals in the
“AND-tree” test mode. The MOE/_TESTOUT pin is
only driven as the test out function when the ZMODE
bit (Chip Control 1 (CCNTL1), bit 7) is set.
JTAG Signals
TCK
TMS
D1
I
I
N/A
N/A
Test Clock. This pin provides the clock for the JTAG
test logic.
E3
Test Mode Select. The signal received at TMS is
decoded by the TAP controller to control JTAG test
operations.
TDI
E2
I
N/A
Test Data In. Serial test instructions are received by
the JTAG test logic at this pin.
TDO
E1
O
4 mA
Test Data Out. This pin is the serial output for test
instructions and data from the JTAG test logic.
Reserved
AB14
Reserved. Not Used.
3-20
Signal Descriptions
3.6 Power and Ground Signals
This section describes the signals for the Power and Ground Signals
group.
Table 3.17 Power and Ground Signals
Name1
Bump
Type Strength Description
VSS
D4, D12, D20,
M4, M10–14,
M20, AA3, AA21,
K10–14, L10–14,
C3, C21, N10–14,
P10–14, Y4, Y12,
Y20.
G
P
N/A
N/A
Ground for PCI bus drivers/receivers, SCSI
bus drivers/receivers, local memory
interface drivers, and other I/O pins.
VDD
D7, D10, D14,
D17, G4, G20,
K4, K20, P4, P20,
U4, U20, Y7, Y10,
Y14, Y17.
Power for PCI bus drivers/receivers, SCSI
bus drivers/receivers, local memory
interface drivers/receivers, and other I/O
pins.
V
V
V
V
DD-Core
SS-Core
DD-A
D3, E4, Y13,
AB18.
P
G
P
G
N/A
N/A
N/A
N/A
Power for core logic.
Ground for core logic.
D2, F3, Y15,
AB19, AC21.
C20
Power for analog cells (clock quadrupler
and diffsense logic).
SS-A
B20
Ground for analog cells (clock quadrupler
and diffsense logic).
V
DD-Bias
M22
A11
P
P
N/A
N/A
Power for LVD bias current.
Power for LVD bias current.
VDD-Bias2
Power and Ground Signals
3-21
Table 3.17 Power and Ground Signals (Cont.)
Name1
Bump
Type Strength Description
RBIAS
M21
I
N/A
N/A
Used to connect an external resistor to
generate the bias current used by LVD Link
pads. Resistor value should be 9.76 kΩ.
Connect other end of resistor to VDD
.
NC
A1, A2, A22, A23, N/A
B1–3, B21–23,
C2, C22, D21,
AB2, AB3, AC1,
AC2, AA22,
These pins have no internal connection.
AB22, AB23.
1. The I/O driver pad rows and digital core have isolated power supplies as indicated by the “I/O” and
“CORE” extensions on their respective VSS and VDD names. These power and ground pins should
be connected directly to the primary power and ground planes of the circuit board. Bypass
capacitors of 0.01 µF should be applied between adjacent VSS and VDD pairs wherever possible.
Do not connect bypass capacitors between VSS and VDD pairs that cross power and ground bus
boundaries.
3-22
Signal Descriptions
3.7 MAD Bus Programming
The MAD[7:0] pins, in addition to serving as the address/data bus for the
local memory interface, also are used to program power-up options for
the chip. A particular option is programmed allowing the internal
pull-down current sink to pull the pin LOW at reset or by connecting a
4.7 kΩ resistor between the appropriate MAD[x] pin and V . The
SS
pull-down resistors require that HC or HCT external components are
used for the memory interface.
•
MAD[7] Serial EEPROM programmable option. When allowed to be
pulled LOW by the internal pull-down current sink, the automatic data
download is enabled. When pulled HIGH by an external resistor, the
automatic data download is disabled. Please see Section 2.4, “Serial
EEPROM Interface” and Subsystem ID and Subsystem Vendor ID
Registers in Chapter 4, “Registers” for additional information.
•
MAD[6] Enable B duplicate SCSI REQ/ and ACK/ signals. When
allowed to be pulled LOW by the internal pull-down current sink, the
duplicate SCSI REQ/ and ACK/ signals for channel B are disabled.
When pulled HIGH by an external resistor, the duplicate SCSI REQ/
and ACK/ signals for channel B are enabled.
•
•
MAD[5] Enable A duplicate SCSI REQ/ and ACK/ signals. When
allowed to be pulled LOW by the internal pull-down current sink, the
duplicate SCSI REQ/ and ACK/ signals for channel A are disabled.
When pulled HIGH by an external resistor, the duplicate SCSI REQ/
and ACK/ signals for channel A are enabled.
MAD[4] INTA/ routing enable. Placing a pull-up resistor on this pin
causes SCSI Function B interrupt requests to appear on the INTA/
pin, along with SCSI Function A interrupt requests, instead of on
INTB/. Placing a pull-up resistor on this pin also causes the SCSI
Function B Interrupt Pin register (0x3D) in PCI configuration space
to be programmed to 0x01 instead of 0x02.
Placing no resistor on this pin causes SCSI Function B interrupt
requests to appear on the INTB/ pin. Placing no resistor on this pin
also causes the SCSI Function B Interrupt Pin register (0x3D) in PCI
configuration space to be programmed to 0x02.
•
The MAD[3:1] pins are used to set the size of the external expansion
ROM device attached. Encoding for these pins is listed in Table 3.18
MAD Bus Programming
3-23
(“0” indicates a pull-down resistor is attached, “1” indicates a pull-up
resistor attached).
Table 3.18 Decode of MAD[3:1] Pins
MAD[3:1] Available Memory Space
000
001
010
011
100
101
110
111
16 Kbytes
32 Kbytes
64 Kbytes
128 Kbytes
256 Kbytes
512 Kbytes
1024 Kbytes
no external memory present
•
•
The MAD[0] pin is the slow ROM pin. When pulled up, it enables two
extra cycles of data access time to allow use of slower memory
devices.
All MAD pins have internal pull-down resistors.
3-24
Signal Descriptions
Chapter 4
Registers
This section contains descriptions of all SYM53C896 registers. The term
“set” is used to refer to bits that are programmed to a binary one.
Similarly, the term “cleared” is used to refer to bits that are programmed
to a binary zero. Write any bits marked as reserved to zero; mask all
information read from them. Reserved bit functions may change at any
time. Unless otherwise indicated, all bits in the registers are active high,
that is, the feature is enabled by setting the bit. The bottom row of every
register diagram shows the default register values, which are enabled
after the chip is powered on or reset.
This chapter contains the following sections:
•
•
•
•
Section 4.1, “PCI Configuration Registers”
Section 4.2, “SCSI Registers”
Section 4.3, “64-Bit SCRIPTS Selectors”
Section 4.4, “Phase Mismatch Jump Registers”
4.1 PCI Configuration Registers
The PCI Configuration registers are accessed by performing a
configuration read/write to the device with its IDSEL pin asserted and the
appropriate value in AD[10:8] during the address phase of the
transaction. SCSI Function A is identified by a binary value of 0b000, and
SCSI Function B by a value of 0b001. Each SCSI function contains the
same register set with identical default values, except the Interrupt Pin
register.
Table 4.1 shows the PCI configuration registers implemented in the
SYM53C896.
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
4-1
All PCI-compliant devices, such as the SYM53C896, must support the
Vendor ID, Device ID, Command, and Status registers. Support of other
PCI-compliant registers is optional. In the SYM53C896, registers that are
not supported are not writable and return all zeros when read. Only those
registers and bits that are currently supported by the SYM53C896 are
described in this chapter.
Note:
Reserved bits should not be accessed.
Table 4.1
PCI Configuration Register Map
31
16 15
0
Device ID
Status
Vendor ID
Command
0x00
0x04
0x08
0x0C
0x10
0x14
0x18
0x1C
0x20
0x24
0x28
0x2C
0x30
0x34
0x38
0x3C
0x40
Class Code
Revision ID (Rev ID)
Not Supported
Header Type
Latency Timer
Cache Line Size
Base Address Register Zero (I/O)
Base Address Register One (MEMORY) bits [31:0]
Base Address Register One (MEMORY) bits [63:32]
Base Address Register Two (SCRIPTS RAM) bits [31:0]
Base Address Register Two (SCRIPTS RAM)) bits [63:32]
Not Supported
Reserved
Subsystem ID
Subsystem Vendor ID
Expansion ROM Base Address
Reserved
Capabilities Pointer
Reserved
Max_Lat
Min_Gnt
Interrupt Pin
Next Item Pointer
Interrupt Line
Capability ID
Power Management Capabilities (PMC)
Bridge Support Exten-
sions (PMCSR_BSE)
Data
Power Management Control/Status (PMCSR)
0x44
Registers:0x00–0x01
Vendor ID
Read Only
15
0
VID
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
VID
Vendor ID
[15:0]
This 16-bit register identifies the manufacturer of the
device. The Vendor ID is 0x1000.
4-2
Registers
Registers:0x02–0x03
Device ID
Read Only
15
0
DID
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
DID
Device ID
[15:0]
This 16-bit register identifies the particular device. The
SYM53C896 Device ID is 0x000B.
Registers:0x04–0x05
Command
Read/Write
15
x
9
x
8
SE
0
7
R
x
6
EPER
0
5
R
x
4
WIE
0
3
R
x
2
1
0
R
x
EBM EMS EIS
x
x
x
x
0
0
0
The Command register provides coarse control over a device’s ability to
generate and respond to PCI cycles. When a zero is written to this
register, the SYM53C896 is logically disconnected from the PCI bus for
all accesses except configuration accesses.
R
Reserved
[15:9]
8
SE
SERR/ Enable
This bit enables the SERR/ driver. SERR/ is disabled
when this bit is cleared. The default value of this bit is
zero. This bit and bit 6 must be set to report address
parity errors.
R
Reserved
7
6
EPER
Enable Parity Error Response
This bit allows the SYM53C896 to detect parity errors on
the PCI bus and report these errors to the system. Only
data parity checking is enabled and disabled with this bit.
The SYM53C896 always generates parity for the PCI
bus.
PCI Configuration Registers
4-3
R
Reserved
5
4
WIE
Write and Invalidate Enable
This bit allows the SYM53C896 to generate write and
invalidate commands on the PCI bus. The WIE bit in the
DMA Control (DCNTL) register must also be set for the
device to generate write and invalidate commands.
R
Reserved
3
EBM
Enable Bus Mastering
2
This bit controls the ability of the SYM53C896 to act as
a master on the PCI bus. A value of zero disables this
device from generating PCI bus master accesses. A
value of one allows the SYM53C896 to behave as a bus
master. The device must be a bus master in order to fetch
SCRIPTS instructions and transfer data.
EMS
Enable Memory Space
1
This bit controls the ability of the SYM53C896 to respond
to Memory space accesses. A value of zero disables the
device response. A value of one allows the SYM53C896
to respond to Memory Space accesses at the address
range specified by the Base Address Register One (MEM-
ORY) and Base Address Register Two (SCRIPTS RAM)
registers in the PCI configuration space.
EIS
Enable I/O Space
0
This bit controls the SYM53C896 response to I/O space
accesses. A value of zero disables the device response.
A value of one allows the SYM53C896 to respond to I/O
Space accesses at the address range specified by the
Base Address Register Zero (I/O) register in the PCI
configuration space.
4-4
Registers
Registers:0x06–0x07
Status
Read/Write
15 14 13 12 11 10
9
8
7
x
5
x
4
NC
1
3
x
0
x
DPE SSE RMA RTA
R
x
DT[1:0] DPR
R
x
R
0
0
0
0
0
0
0
x
x
Reads to this register behave normally. Writes are slightly different in that
bits can be cleared, but not set. A bit is cleared whenever the register is
written, and the data in the corresponding bit location is a one. For
instance, to clear bit 15 and not affect any other bits, write the value
0x8000 to the register.
DPE
Detected Parity Error (from Slave)
15
This bit is set by the SYM53C896 whenever it detects a
data parity error, even if data parity error handling is
disabled.
SSE
Signaled System Error
14
This bit is set whenever the device asserts the SERR/
signal.
RMA
Received Master Abort (from Master)
A master device should set this bit whenever its
transaction (except for Special Cycle) is terminated with
Master Abort.
13
RTA
Received Target Abort (from Master)
A master device should set this bit whenever its
transaction is terminated by target abort.
12
R
Reserved
11
DT[1:0]
DEVSEL/ Timing
[10:9]
These bits encode the timing of DEVSEL/. These are
encoded as:
0b00
0b01
0b10
0b11
fast
medium
slow
reserved
PCI Configuration Registers
4-5
These bits are read only and should indicate the slowest
time that a device asserts DEVSEL/ for any bus
command except Configuration Read and Configuration
Write. The SYM53C896 supports a value of 0b01.
DPR
Data Parity Error Reported
8
This bit is set when the following conditions are met:
•
•
•
The bus agent asserted PERR/ itself or observed
PERR/ asserted and;
The agent setting this bit acted as the bus master for
the operation in which the error occurred and;
The Parity Error Response bit in the Command
register is set.
R
Reserved
[7:5]
4
NC
New Capabilities
This bit is set to indicate a list of extended capabilities
such as PCI Power Management. This bit is read only.
R
Reserved
[3:0]
Register: 0x08
Revision ID (Rev ID)
Read Only
7
0
RID
0
0
0
0
X
X
X
X
RID
Revision ID
[7:0]
This register specifies a device specific revision identifier.
The upper nibble is always set to 0x0000. The lower
nibble reflects the current revision level of the device.
4-6
Registers
Registers:0x09–0x0B
Class Code
Read Only
23
0
0
0
CC
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
CC
Class Code
[23:0]
This 24-bit register is used to identify the generic function
of the device. The upper byte of this register is a base
class code, the middle byte is a subclass code, and the
lower byte identifies a specific register-level programming
interface. The value of this register is 0x010000, which
identifies a SCSI controller.
Register: 0x0C
Cache Line Size
Read/Write
7
0
0
CLS
0
0
0
0
0
0
0
CLS
Cache Line Size
[7:0]
This register specifies the system cache line size in units
of 32-bit words. The value in this register is used by the
device to determine whether to use Write and Invalidate
or Write commands for performing write cycles, and
whether to use Read, Read Line, or Read Multiple
commands for performing read cycles as a bus master.
Devices participating in the caching protocol use this field
to know when to retry burst accesses at cache line
boundaries. These devices can ignore the PCI cache
support lines (SDONE and SB0/) when this register is set
to 0. If this register is programmed to a number which is
not a power of 2, the device will not use PCI performance
commands to perform data transfers.
PCI Configuration Registers
4-7
Register: 0x0D
Latency Timer
Read/Write
7
0
0
LT
0
0
0
0
0
0
0
LT
Latency Timer
[7:0]
The Latency Timer register specifies, in units of PCI bus
clocks, the value of the Latency Timer for this PCI bus
master. The SCSI functions of the SYM53C896 support
this timer. All eight bits are writable, allowing latency
values of 0–255 PCI clocks. Use the following equation to
calculate an optimum latency value for the SCSI functions
of the SYM53C896.
Latency = 2 + (Burst Size x (typical wait states + 1))
Values greater than optimum are also acceptable.
Register: 0x0E
Header Type
Read Only
7
0
0
HT
0
0
0
0
0
0
0
HT
Header Type
[7:0]
This 8-bit register identifies the layout of bytes 0x10
through 0x3F in configuration space and also whether or
not the device contains multiple functions. Since the
SYM53C896 is a multifunction controller the value of this
register is 0x80.
Register: 0x0F
Not Supported
4-8
Registers
Registers:0x10–0x13
Base Address Register Zero (I/O)
Read/Write
31
0
0
1
BAR0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
BAR0
Base Address Register Zero - I/O
[31:0]
This base address register is used to map the operating
register set into I/O space. The SYM53C896 requires 256
bytes of I/O space for this base address register. It has
bit zero hardwired to one. Bit 1 is reserved and returns a
zero on all reads, and the other bits are used to map the
device into I/O space. For detailed information on the
operation of this register, refer to the PCI 2.1
specification.
Registers:0x14–0x1B
Base Address Register One (MEMORY)
Read/Write
63
32
BAR1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
31
BAR1
0
0
0
0
BAR1
Base Address Register One
This base address register maps SCSI operating
registers into memory space. This device requires
[63:0]
1024 bytes of address space for this base register. This
register has bits [9:0] hardwired to 0b0000000100. The
default value of this register is 0x0000000000000004. For
detailed information on the operation of this register, refer
to the PCI 2.1 specification.
PCI Configuration Registers
4-9
Registers:0x1C–0x23
Base Address Register Two (SCRIPTS RAM)
Read/Write
63
32
BAR2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
31
BAR2
0
0
0
0
BAR2
Base Address Register Two
[63:0]
This base register is used to map the SCRIPTS RAM into
memory space. The default value of this register is
0x0000000000000004.
The SYM53C896 requires 8192 bytes of address space
for this base register. This register has bits [12:0]
hardwired to 0b0000000000100.
For detailed information on the operation of this register,
refer to the PCI 2.1 specification.
Registers:0x24–0x27
Not Supported
Registers:0x28–0x2B
Reserved
4-10
Registers
Registers:0x2C–0x2D
Subsystem Vendor ID
Read Only
15
0
0
SVID
If MAD[7] Is HIGH
0
0
0
1
x
0
x
0
x
0
x
0
0
x
0
x
0
x
0
x
0
x
0
x
0
x
If MAD[7] is LOW
x
x
x
x
x
SVID
Subsystem Vendor ID
[15:0]
This 16-bit register is used to uniquely identify the vendor
manufacturing the add-in board or subsystem where this
PCI device resides. It provides a mechanism for an
add-in card vendor to distinguish its cards from another
vendor’s cards, even if the cards have the same PCI
controller installed on them (and therefore the same
Vendor ID and Device ID).
If the external serial EEPROM interface is enabled
(MAD[7] LOW), this register is automatically loaded at
power-up from the external serial EEPROM and will
contain the value downloaded from the serial EEPROM
or a value of 0x0000 if the download fails.
If the external serial EEPROM interface is disabled
(MAD[7] HIGH), this register returns a value of 0x1000.
The 16-bit value that should be stored in the external
serial EEPROM for this register is the vendor’s PCI
Vendor ID and must be obtained from the PCI Special
Interest Group (SIG). Please see Section 2.4, “Serial
EEPROM Interface” for more information on downloading
a value for this register.
PCI Configuration Registers
4-11
Registers:0x2E–0x2F
Subsystem ID
Read Only
15
0
0
SID
If MAD[7] Is HIGH
0
0
0
1
x
0
x
0
x
0
x
0
x
0
x
0
x
0
x
0
x
0
x
0
x
0
x
If MAD[7] is LOW
x
x
x
x
SID
Subsystem ID
[15:0]
This 16-bit register is used to uniquely identify the add-in
board or subsystem where this PCI device resides. It
provides a mechanism for an add-in card vendor to
distinguish its cards from one another even if the cards
have the same PCI controller installed on them (and
therefore the same Vendor ID and Device ID).
If the external serial EEPROM interface is enabled
(MAD[7] is LOW), this register is automatically loaded at
power-up from the external serial EEPROM and will
contain the value downloaded from the serial EEPROM
or a value of 0x0000 if the download fails.
If the external serial EEPROM is disabled (MAD[7] pulled
HIGH), the register returns a value of 0x1000. The 16-bit
value that should be stored in the external serial
EEPROM is vendor specific. Please see Section 2.4,
“Serial EEPROM Interface” for additional information on
downloading a value for this register.
Registers:0x30–0x33
Expansion ROM Base Address
Read/Write
31
0
0
1
ERBA
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
ERBA
Expansion ROM Base Address
[31:0]
This four-byte register handles the base address and size
information for the expansion ROM. It functions exactly
4-12
Registers
like the Base Address Register Zero (I/O) and Base
Address Register One (MEMORY) registers, except that
the encoding of the bits is different. The upper 21 bits
correspond to the upper 21 bits of the expansion ROM
base address.
The expansion ROM Enable bit, bit 0, is the only bit
defined in this register. This bit is used to control whether
or not the device accepts accesses to its expansion
ROM. When the bit is set, address decoding is enabled,
and a device is used with or without an expansion ROM
depending on the system configuration. To access the
external memory interface, also set the Memory Space
bit in the Command register.
The host system detects the size of the external memory
by first writing the Expansion ROM Base Address register
with all ones and then reading back the register. The
SCSI functions of the SYM53C896 respond with zeros in
all don’t care locations. The ones in the remaining bits
represent the binary version of the external memory size.
For example, to indicate an external memory size of
32 Kbytes, this register, when written with ones and read
back, returns ones in the upper 17 bits.
The size of the external memory is set through MAD[3:1].
Please see Section 3.7, “MAD Bus Programming” for the
possible size encodings available.
Register: 0x34
Capabilities Pointer
Read Only
7
0
0
CP
0
1
0
0
0
0
0
CP
Capabilities Pointer
[7:0]
This register indicates that the first extended capability
register is located at offset 0x40 in the PCI Configuration.
Registers:0x35–0x3B
Reserved
PCI Configuration Registers
4-13
Register: 0x3C
Interrupt Line
Read/Write
7
0
0
IL
0
0
0
0
0
0
0
IL
Interrupt Line
[7:0]
This register is used to communicate interrupt line routing
information. POST software writes the routing information
into this register as it configures the system. The value in
this register tells which input of the system interrupt
controller(s) the device’s interrupt pin is connected to.
Values in this register are specified by system
architecture.
Register: 0x3D
Interrupt Pin
Read Only
7
0
IP
SCSI Function A
0
0
0
0
0
0
0
0
0
0
0
1
0
1
0
1
SCSI Function B if MAD[4] pulled LOW
0
0
0
0
SCSI Function B if MAD[4] pulled HIGH
0
0
0
0
IP
Interrupt Pin
[7:0]
This register is unique to each SCSI function. It tells
which interrupt pin the device uses. Its value is set to
0x01 for the Function A (INTA/) signal, and 0x02 for the
Function B (INTB/) signal at power-up if MAD[4] is pulled
LOW. The Function B value is set to 0x01 (INTA/) if
MAD[4] is pulled HIGH.
Note:
Please see Section 3.7, “MAD Bus Programming” for
additional information.
4-14
Registers
Register: 0x3E
Min_Gnt
Read Only
7
0
1
MG
0
0
0
1
0
0
0
MG
Min_Gnt
[7:0]
This register is used to specify the desired settings for
latency timer values. Min_Gnt is used to specify how long
a burst period the device needs. The value specified in
these registers is in units of 0.25 microseconds. The
SYM53C896 sets this register to 0x11.
Register: 0x3F
Max_Lat
Read Only
7
0
0
ML
0
1
0
0
0
0
0
ML
Max_Lat
[7:0]
This register is used to specify the desired settings for
latency timer values. Max_Lat is used to specify how
often the device needs to gain access to the PCI bus.
The value specified in these registers is in units of 0.25
microseconds. The SYM53C896 SCSI function sets this
register to 0x40.
PCI Configuration Registers
4-15
Register: 0x40
Capability ID
Read Only
7
0
1
CID
0
0
0
0
0
0
0
CID
Cap_ID
[7:0]
This register indicates the type of data structure currently
being used. It is set to 0x01, indicating the Power
Management Data Structure.
Register: 0x41
Next Item Pointer
Read Only
7
0
0
NIP
0
0
0
0
0
0
0
NIP
Next_Item_Ptr
[7:0]
Bits [7:0] contain the offset location of the next item in the
function’s capabilities list. The SYM53C896 has these
bits set to zero indicating no further extended capabilities
registers exist.
Registers:0x42–0x43
Power Management Capabilities (PMC)
Read Only
15
0
11
0
10
9
8
0
6
0
5
DSI
0
4
R
0
3
PMEC
0
2
0
0
0
PMES
0
D2S D1S
AUXC
0
VER[2:0]
1
0
0
1
1
PMES
PME_Support
[15:11]
Bits [15:11] define the power management states in
which the SYM53C896 will assert the PME pin. These
bits are all set to zero because the SYM53C896 does not
provide a PME signal.
4-16
Registers
D2S
D1S
AUXC
DSI
D2_Support
10
9
The SYM53C896 sets this bit to indicate support for
power management state D2.
D1_Support
The SYM53C896 sets this bit to indicate support for
power management state D1.
Aux_Current
[8:6]
The SYM53C896 always returns zeros. This feature is
not supported.
Device Specific Initialization
5
This bit is cleared to indicate that the SYM53C896
requires no special initialization before the generic class
device driver is able to use it.
R
Reserved
4
PMEC
PME Clock
3
Bit 3 is cleared because the SYM53C896 does not
provide a PME pin.
VER[2:0]
Version
[2:0]
These three bits are set to 0b010 to indicate that the
SYM53C896 complies with Revision 1.1 of the PCI Power
Management Interface Specification.
Registers:0x44–0x45
Power Management Control/Status (PMCSR)
Read/Write
15
14
13 12
9
0
8
PEN
0
7
x
2
x
0
PST DSCL[1:0]
DSLT[3:0]
R
PWS[1:0]
0
0
0
0
0
0
x
x
x
x
0
0
PST
PME_Status
The SYM53C896 always returns a zero for this bit,
15
indicating that PME signal generation is not supported
from D3cold.
DSCL[1:0]
Data_Scale
[14:13]
The SYM53C896 does not support the data register.
Therefore, these two bits are always cleared.
PCI Configuration Registers
4-17
DSLT[3:0]
PEN
Data_Select
[12:9]
The SYM53C896 does not support the data register.
Therefore, these four bits are always cleared.
PME_Enable
8
The SYM53C896 always returns zero for this bit to
indicate that PME assertion is disabled.
R
Reserved
[7:2]
[1:0]
PWS[1:0]
Power State
Bits [1:0] are used to determine the current power state
of the SYM53C896. They are used to place the
SYM53C896 in a new power state. Power states are
defined as:
0b00
0b01
0b10
0b11
D0
D1
D2
D3 hot
See the Section 2.5, “Power Management” for descriptions
of the Power Management States.
Register: 0x46
Bridge Support Extensions (PMCSR_BSE)
Read Only
7
0
0
BSE
0
0
0
0
0
0
0
BSE
Bridge Support Extensions
[7:0]
This register indicates PCI Bridge specific functionality.
The SYM53C896 always returns 0x00.
4-18
Registers
Register: 0x47
Data
Read Only
7
0
0
DATA
0
0
0
0
0
0
0
DATA
Data
[7:0]
This register provides an optional mechanism for the
function to report state-dependent operating data. The
SYM53C896 always returns 0x00.
PCI Configuration Registers
4-19
4.2 SCSI Registers
The control registers for the SCSI core are directly accessible from the
PCI bus using Memory or I/O mapping. Each SCSI function has the
identical register set. The address map of the SCSI registers is shown in
Table 4.2.
Note:
The only registers that the host CPU can access while the
SYM53C896 is executing SCRIPTS are the Interrupt Status
Zero (ISTAT0), Interrupt Status One (ISTAT1), Mailbox Zero
(MBOX0), and Mailbox One (MBOX1) registers. Attempts to
access other registers interfere with the operation of the
chip. However, all operating registers are accessible with
SCRIPTS. All read data is synchronized and stable when
presented to the PCI bus.
4-20
Registers
Table 4.2
SCSI Register Map
31
16 15
0
SCNTL3
SCNTL2
SDID
SCNTL1
SXFER
SOCL
SCNTL0
SCID
0x00
0x04
0x08
0x0C
0x10
0x14
0x18
0x1C
0x20
0x24
0x28
0x2C
0x30
0x34
0x38
0x3C
0x40
0x44
0x48
0x4C
0x50
0x54
0x58
0x5C
0x60
0xA0
0xA4
0xA8
0xAC
0xB0
0xB4
0xB8
0xBC
0xC0
0xC4
0xC8
0xCC
0xD0
0xD4
0xD8
0xDC
0xE0–0xFF
GPREG
SBCL
SSID
SFBR
SSTAT2
SSTAT1
SSTAT0
DSTAT
DSA
MBOX1
MBOX0
ISTAT1
ISTAT0
CTEST3
CTEST2
CTEST1
CTEST0
TEMP
CTEST6
DCMD
CTEST5
CTEST4
DBC
DFIFO
DNAD
DSP
DSPS
SCRATCH A
DCNTL
SBR
DIEN
DMODE
ADDER
SIST1
SIST0
CTYPE
SIEN1
SWIDE
STIME1
STEST1
SIEN0
SLPAR
STIME0
STEST0
GPCNTL
RESPID1
STEST3
Reserved
CCNTL1
RESPID0
STEST2
STEST4
CCNTL0
SIDL
SODL
SBDL
Reserved
SCRATCH B
SCRATCH C–SCRATCH R
MMRS
MMWS
SFS
DRS
SBMS
DBMS
DNAD64
Reserved
PMJAD1
PMJAD2
RBC
UA
ESA
IA
Reserved
SBC
CSBC
Reserved
SCSI Registers
4-21
Register: 0x00
SCSI Control Zero (SCNTL0)
Read/Write
7
1
6
1
5
START
0
4
WATN
0
3
EPC
0
2
R
x
1
AAP
0
0
TRG
0
ARB[1:0]
ARB[1:0]
Arbitration Mode Bits 1 and 0
[7:6]
ARB1 ARB0
Arbitration Mode
0
0
1
1
0
1
0
1
Simple arbitration
Reserved
Reserved
Full arbitration, selection/reselection
Simple Arbitration
1. The SYM53C896 SCSI function waits for a bus free
condition to occur.
2. It asserts SBSY/ and its SCSI ID (contained in the
SCSI Chip ID (SCID) register) onto the SCSI bus. If
the SSEL/ signal is asserted by another SCSI
device, the SYM53C896 SCSI function deasserts
SBSY/, deasserts its ID and sets the Lost Arbitration
bit (bit 3) in the SCSI Status Zero (SSTAT0) register.
3. After an arbitration delay, the CPU should read the
SCSI Bus Data Lines (SBDL) register to check if a
higher priority SCSI ID is present. If no higher
priority ID bit is set, and the Lost Arbitration bit is not
set, the SYM53C896 SCSI function wins arbitration.
4. Once the SYM53C896 SCSI function wins
arbitration, SSEL/ must be asserted using the SCSI
Output Control Latch (SOCL) for a bus clear plus a
bus settle delay (1.2 µs) before a low level selection
is performed.
4-22
Registers
Full Arbitration, Selection/Reselection
1. The SYM53C896 SCSI function waits for a bus free
condition.
2. It asserts SBSY/ and its SCSI ID (the highest priority
ID stored in the SCSI Chip ID (SCID) register) onto
the SCSI bus.
3. If the SSEL/ signal is asserted by another SCSI
device or if the SYM53C896 SCSI function detects a
higher priority ID, the SYM53C896 SCSI function
deasserts SBSY, deasserts its ID, and waits until the
next bus free state to try arbitration again.
4. The SYM53C896 SCSI function repeats arbitration
until it wins control of the SCSI bus. When it wins,
the Won Arbitration bit is set in the SCSI Status Zero
(SSTAT0) register, bit 2.
5. The SYM53C896 SCSI function performs selection
by asserting the following onto the SCSI bus: SSEL/,
the target’s ID (stored in the SCSI Destination ID
(SDID) register), and the SYM53C896’s ID (stored in
the SCSI Chip ID (SCID) register).
6. After a selection is complete, the Function Complete
bit is set in the SCSI Interrupt Status Zero (SIST0)
register, bit 6.
7. If a selection time-out occurs, the Selection
Time-Out bit is set in the SCSI Interrupt Status One
(SIST1) register, bit 2.
START
Start Sequence
5
When this bit is set, the SYM53C896 starts the arbitration
sequence indicated by the Arbitration Mode bits. The
Start Sequence bit is accessed directly in low level mode.
During SCSI SCRIPTS operations, this bit is controlled by
the SCRIPTS processor. Do not start an arbitration
sequence if the connected (CON) bit in the SCSI Control
One (SCNTL1) register, bit 4, indicates that the
SYM53C896 is already connected to the SCSI bus. This
bit is automatically cleared when the arbitration sequence
is complete. If a sequence is aborted, check bit 4 in the
SCNTL1 register to verify that the SYM53C896 is not
connected to the SCSI bus.
SCSI Registers
4-23
WATN
Select with SATN/ on a Start Sequence
4
When this bit is set and the SYM53C896 SCSI function
is in the initiator mode, the SATN/ signal is asserted
during selection of a SCSI target device. This is to inform
the target that the SYM53C896 SCSI function has a
message to send. If a selection time-out occurs while
attempting to select a target device, SATN/ is deasserted
at the same time SSEL/ is deasserted. When this bit is
cleared, the SATN/ signal is not asserted during
selection. When executing SCSI SCRIPTS, this bit is
controlled by the SCRIPTS processor, but manual setting
is possible in low level mode.
EPC
Enable Parity Checking
3
When this bit is set, the SCSI data bus is checked for odd
parity when data is received from the SCSI bus in either
the initiator or target mode. If a parity error is detected,
bit 0 of the SCSI Interrupt Status Zero (SIST0) register is
set and an interrupt may be generated.
If the SYM53C896 SCSI function is operating in the
initiator mode and a parity error is detected, assertion of
SATN/ is optional, but the transfer continues until the
target changes phase. When this bit is cleared, parity
errors are not reported.
R
Reserved
2
AAP
Assert SATN/ on Parity Error
1
When this bit is set, the SYM53C896 SCSI function
automatically asserts the SATN/ signal upon detection of
a parity error. SATN/ is only asserted in the initiator
mode. The SATN/ signal is asserted before deasserting
SACK/ during the byte transfer with the parity error. Also
set the Enable Parity Checking bit for the SYM53C896
SCSI function to assert SATN/ in this manner. A parity
error is detected on data received from the SCSI bus.
If the Assert SATN/ on Parity Error bit is cleared or the
Enable Parity Checking bit is cleared, SATN/ is not
automatically asserted on the SCSI bus when a parity
error is received.
TRG
Target Mode
0
This bit determines the default operating mode of the
SYM53C896 SCSI function. The user must manually set
4-24
Registers
the target or initiator mode. This is done using the
SCRIPTS language (SET TARGET or CLEAR TARGET).
When this bit is set, the chip is a target device by default.
When this bit is cleared, the SYM53C896 SCSI function
is an initiator device by default.
Caution:
Writing this bit while not connected may cause the loss of
a selection or reselection due to the changing of target or
initiator modes.
Register: 0x01
SCSI Control One (SCNTL1)
Read/Write
7
EXC
0
6
ADB
0
5
DHP
0
4
CON
0
3
RST
0
2
AESP
0
1
IARB
0
0
SST
0
EXC
Extra Clock Cycle of Data Setup
7
When this bit is set, an extra clock period of data setup
is added to each SCSI data transfer. The extra data setup
time can provide additional system design margin, though
it affects the SCSI transfer rates. Clearing this bit disables
the extra clock cycle of data setup time. Setting this bit
only affects SCSI send operations.
ADB
Assert SCSI Data Bus
6
When this bit is set, the SYM53C896 SCSI function
drives the contents of the SCSI Output Data Latch (SODL)
register onto the SCSI data bus. When the SYM53C896
SCSI function is an initiator, the SCSI I/O signal must be
inactive to assert the SODL contents onto the SCSI bus.
When the SYM53C896 SCSI function is a target, the
SCSI I/O signal must be active to assert the SODL con-
tents onto the SCSI bus. The contents of the SODL reg-
ister can be asserted at any time, even before the
SYM53C896 SCSI function is connected to the SCSI bus.
Clear this bit when executing SCSI SCRIPTS. It is nor-
mally used only for diagnostic testing or operation in low
level mode.
SCSI Registers
4-25
DHP
Disable Halt on Parity Error or ATN (Target Only)
The DHP bit is only defined for the target mode. When
this bit is cleared, the SYM53C896 SCSI function halts
5
the SCSI data transfer when a parity error is detected or
when the SATN/ signal is asserted. If SATN/ or a parity
error is received in the middle of a data transfer, the
SYM53C896 SCSI function may transfer up to three
additional bytes before halting to synchronize between
internal core cells. During synchronous operation, the
SYM53C896 SCSI function transfers data until there are
no outstanding synchronous offsets. If the SYM53C896
SCSI function is receiving data, any data residing in the
DMA FIFO is sent to memory before halting.
When this bit is set, the SYM53C896 SCSI function does
not halt the SCSI transfer when SATN/ or a parity error is
received.
CON
Connected
4
This bit is automatically set any time the SYM53C896
SCSI function is connected to the SCSI bus as an initiator
or as a target. It is set after the SYM53C896 SCSI
function successfully completes arbitration or when it has
responded to a bus initiated selection or reselection. This
bit is also set after the chip wins simple arbitration when
operating in low level mode. When this bit is cleared, the
SYM53C896 SCSI function is not connected to the SCSI
bus.
The CPU can force a connected or disconnected
condition by setting or clearing this bit. This feature is
used primarily during loopback mode.
RST
Assert SCSI RST/ Signal
3
Setting this bit asserts the SRST/ signal. The SRST/
output remains asserted until this bit is cleared. The
25 µs minimum assertion time defined in the SCSI
specification must be timed out by the controlling
microprocessor or a SCRIPTS loop.
AESP
Assert Even SCSI Parity (force bad parity)
2
When this bit is set, the SYM53C896 SCSI function
asserts even parity. It forces a SCSI parity error on each
byte sent to the SCSI bus from the chip. If parity checking
is enabled, then the SYM53C896 SCSI function checks
4-26
Registers
data received for odd parity. This bit is used for diagnostic
testing and is cleared for normal operation. It is useful to
generate parity errors to test error handling functions.
IARB
Immediate Arbitration
1
Setting this bit causes the SCSI core to immediately
begin arbitration once a Bus Free phase is detected
following an expected SCSI disconnect. This bit is useful
for multithreaded applications. The ARB[1:0] bits in SCSI
Control Zero (SCNTL0) are set for full arbitration and
selection before setting this bit.
Arbitration is retried until won. At that point, the
SYM53C896 SCSI function holds SBSY and SSEL
asserted, and waits for a select or reselect sequence.
The Immediate Arbitration bit is cleared automatically
when the selection or reselection sequence is completed,
or times out.
An unexpected disconnect condition clears IARB with it
attempting arbitration. See the SCSI Disconnect
Unexpected bit (SCSI Control Two (SCNTL2), bit 7) for
more information on expected versus unexpected
disconnects.
It is possible to abort an immediate arbitration sequence.
First, set the Abort bit in the Interrupt Status Zero (ISTAT0)
register. Then one of two things eventually happens:
•
The Won Arbitration bit (SCSI Status Zero (SSTAT0) bit
2) will be set. In this case, the Immediate Arbitration
bit needs to be cleared. This completes the abort
sequence and disconnects the chip from the SCSI
bus. If it is not acceptable to go to Bus Free phase
immediately following the arbitration phase, it is pos-
sible to perform a low level selection instead.
•
The abort completes because the SYM53C896 SCSI
function loses arbitration. This is detected by the
clearing of the Immediate Arbitration bit. Do not use
the Lost Arbitration bit (SCSI Status Zero (SSTAT0)
bit 3) to detect this condition. In this case take no
further action.
SST
Start SCSI Transfer
0
This bit is automatically set during SCRIPTS execution
and should not be used. It causes the SCSI core to begin
a SCSI transfer, including SREQ/ and SACK/
handshaking. The determination of whether the transfer
SCSI Registers
4-27
is a send or receive is made according to the value
written to the I/O bit in SCSI Output Control Latch (SOCL).
This bit is self-clearing. Do not set it for low level
operation.
Caution:
Writing to this register while not connected may cause the
loss of a selection/reselection by clearing the Connected
bit.
Register: 0x02
SCSI Control Two (SCNTL2)
Read/Write
7
SDU
0
6
CHM
0
5
4
3
WSS
0
2
VUE0
0
1
VUE1
0
0
WSR
0
SLPMD SLPHBEN
0
0
SDU
SCSI Disconnect Unexpected
7
This bit is valid in the initiator mode only. When this bit is
set, the SCSI core is not expecting the SCSI bus to enter
the Bus Free phase. If it does, an unexpected disconnect
error is generated (see the Unexpected Disconnect bit in
the SCSI Interrupt Status Zero (SIST0) register, bit 2). Dur-
ing normal SCRIPTS mode operation, this bit is set auto-
matically whenever the SCSI core is reselected, or
successfully selects another SCSI device. The SDU bit
should be cleared with a register write (Move 0x00 To
SCSI Control Two (SCNTL2)) before the SCSI core
expects a disconnect to occur, normally prior to sending
an Abort, Abort Tag, Bus Device Reset, Clear Queue or
Release Recovery message, or before deasserting
SACK/ after receiving a Disconnect command or
Command Complete message.
CHM
Chained Mode
6
This bit determines whether or not the SCSI core is
programmed for chained SCSI mode. This bit is
automatically set by the Chained Block Move (CHMOV)
SCRIPTS instruction and is automatically cleared by the
Block Move SCRIPTS instruction (MOVE).
Chained mode is primarily used to transfer consecutive
wide data blocks. Using chained mode facilitates partial
receive transfers and allows correct partial send behavior.
4-28
Registers
When this bit is set and a data transfer ends on an odd
byte boundary, the SYM53C896 SCSI function stores the
last byte in the SCSI Wide Residue (SWIDE) register
during a receive operation, or in the SCSI Output Data
Latch (SODL) register during a send operation. This byte
is combined with the first byte from the subsequent
transfer so that a wide transfer is completed.
SLPMD
SLPAR Mode
5
If this bit is cleared, the SCSI Longitudinal Parity (SLPAR)
register functions as a byte-wide longitudinal parity
register. If this bit is set, the SLPAR functions as a
word-wide longitudinal parity function. The high or low
byte of the SLPAR word is accessible through the SLPAR
register. Which byte is accessible is controlled by the
SLPHBEN bit.
SLPHBEN
WSS
SLPAR High Byte Enable
4
If this bit is cleared, the low byte of the SLPAR word is
accessible through the SCSI Longitudinal Parity (SLPAR)
register. If this bit is set, the high byte of the SLPAR word
is present in the SLPAR register.
Wide SCSI Send
3
When read, this bit returns the value of the Wide SCSI
Send (WSS) flag. Asserting this bit clears the WSS flag.
This clearing function is self-clearing.
When the WSS flag is high following a wide SCSI send
operation, the SCSI core is holding a byte of “chain” data
in the SCSI Output Data Latch (SODL) register. This data
becomes the first low-order byte sent when married with
a high-order byte during a subsequent data send transfer.
Performing a SCSI receive operation clears this bit. Also,
performing any nonwide transfer clears this bit.
VUE0
Vendor Unique Enhancements, Bit 0
2
This bit is a read only value indicating whether the group
code field in the SCSI instruction is standard or vendor
unique. If cleared, the bit indicates standard group codes;
if set, the bit indicates vendor unique group codes. The
value in this bit is reloaded at the beginning of all
asynchronous target receives.
SCSI Registers
4-29
VUE1
WSR
Vendor Unique Enhancement, Bit 1
1
This bit is used to disable the automatic byte count reload
during Block Move instructions in the command phase. If
this bit is cleared, the device reloads the Block Move byte
count if the first byte received is one of the standard
group codes. If this bit is set, the device does not reload
the Block Move byte count, regardless of the group code.
Wide SCSI Receive
0
When read, this bit returns the value of the Wide SCSI
Receive (WSR) flag. Setting this bit clears the WSR flag.
This clearing function is self-clearing.
The WSR flag indicates that the SCSI core received data
from the SCSI bus, detected a possible partial transfer at
the end of a chained or nonchained block move
command, and temporarily stored the high-order byte in
the SCSI Wide Residue (SWIDE) register rather than
passing the byte out the DMA channel. The hardware
uses the WSR status flag to determine what behavior
must occur at the start of the next data receive transfer.
When the flag is set, the stored data in SWIDE may be
“residue” data, valid data for a subsequent data transfer,
or overrun data. The byte is read as normal data by
starting a data receive transfer.
Performing a SCSI send operation clears this bit. Also,
performing any nonwide transfer clears this bit.
Register: 0x03
SCSI Control Three (SCNTL3)
Read/Write
7
USE
0
6
0
4
0
3
EWS
0
2
0
0
0
SCF[2:0]
0
CCF[2:0]
0
USE
Ultra SCSI Enable
Setting this bit enables Ultra SCSI or Ultra2 SCSI
7
synchronous transfers. The default value of this bit is 0.
This bit should remain cleared if the SYM53C896 is not
operating in Ultra SCSI mode or faster.
When this bit is set, the signal filtering period for SREQ/
and SACK/ automatically changes to 8 ns for Ultra2 SCSI
4-30
Registers
or 15 ns for Ultra SCSI, regardless of the value of the
Extend REQ/ACK Filtering bit in the SCSI Test Two
(STEST2) register.
Note:
Set this bit to achieve Ultra SCSI transfer rates in legacy
systems that use an 80 MHz clock.
SCF[2:0]
Synchronous Clock Conversion Factor
[6:4]
These bits select a factor by which the frequency of
SCLK is divided before being presented to the
synchronous SCSI control logic. Write these to the same
value as the Clock Conversion Factor bits below unless
fast SCSI operation is desired. See the SCSI Transfer
(SXFER) register description for examples of how the
SCF bits are used to calculate synchronous transfer
periods. See the table under the description of bits [7:5]
of the SXFER register for the valid combinations.
EWS
Enable Wide SCSI
3
When this bit is cleared, all information transfer phases
are assumed to be eight bits, transmitted on SD[7:0]/ and
SDP0/. When this bit is asserted, data transfers are done
16 bits at a time, with the least significant byte on
SD[7:0]/ and SDP0/ and the most significant byte on
SD[15:8]/, SDP1/. Command, Status, and Message
phases are not affected by this bit.
CCF[2:0]
Clock Conversion Factor
[2:0]
These bits select a factor by which the frequency of
SCLK is divided before being presented to the SCSI core.
The synchronous portion of the SCSI core can be run at
a different clock rate for fast SCSI, using the
Synchronous Clock Conversion Factor bits. The bit
encoding is displayed in the table below. All other
combinations are reserved.
SCSI Registers
4-31
SCF2
CCF2
SCF1
CCF1
SCF0
CCF0
Factor
Frequency
SCSI Clock
(MHz)
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
SCLK/3
SCLK/1
SCLK/1.5
SCLK/2
SCLK/3
SCLK/4
SCLK/6
SCLK/8
50.01–75.0
16.67–25.0
25.01–37.5
37.51–50.0
50.01–75.0
75.01–80.00
120
160
Note:
It is important that these bits are set to the proper values
to guarantee that the SYM53C896 meets the SCSI timings
as defined by the ANSI specification.
Register: 0x04
SCSI Chip ID (SCID)
Read/Write
7
R
x
6
RRE
0
5
SRE
0
4
R
x
3
0
0
0
ENC[3:0]
0
0
R
Reserved
7
6
RRE
Enable Response to Reselection
When this bit is set, the SYM53C896 SCSI function is
enabled to respond to bus-initiated reselection at the chip
ID in the Response ID Zero (RESPID0) and Response ID
One (RESPID1) registers. Note that the chip does not
automatically reconfigure itself to the initiator mode as a
result of being reselected.
SRE
Enable Response to Selection
5
When this bit is set, the SYM53C896 SCSI function is
able to respond to bus-initiated selection at the chip ID in
the Response ID Zero (RESPID0) and Response ID One
(RESPID1) registers. Note that the chip does not
automatically reconfigure itself to target mode as a result
of being selected.
4-32
Registers
R
Reserved
4
ENC[3:0]
Encoded Chip SCSI ID
[3:0]
These bits are used to store the SYM53C896 SCSI
function encoded SCSI ID. This is the ID which the chip
asserts when arbitrating for the SCSI bus. The IDs that
the SYM53C896 SCSI function responds to when
selected or reselected are configured in the Response ID
Zero (RESPID0) and Response ID One (RESPID1)
registers. The priority of the 16 possible IDs, in
descending order is:
Highest
Lowest
7
6
5
4
3
2
1
0 15 14 13 12 11 10 9
8
Register: 0x05
SCSI Transfer (SXFER)
Read/Write
7
0
5
0
4
0
TP[2:0]
0
MO[4:0]
0
0
0
0
0
Note:
When using Table Indirect I/O commands, bits [7:0] of this
register are loaded from the I/O data structure.
TP[2:0]
SCSI Synchronous Transfer Period
[7:5]
These bits determine the SCSI synchronous transfer
period used by the SYM53C896 SCSI function when
sending synchronous SCSI data in either the initiator or
target mode. These bits control the programmable
dividers in the chip.
SCSI Registers
4-33
TP2
TP1
TP0
XFERP
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
4
5
6
7
8
9
10
11
The synchronous transfer period the SYM53C896 should
use when transferring SCSI data is determined in the
following example:
The SYM53C896 is connected to a hard disk which can
transfer data at 10 Mbytes/s synchronously. The
SYM53C896 SCSI function’s SCLK is running at 40 MHz.
The synchronous transfer period (SXFERP) is found as
follows:
SXFERP = Period/SSCP + ExtCC
Period = 1 ÷ Frequency = 1 ÷ 10 Mbytes/s = 100 ns
SSCP = 1 ÷ SSCF = 1 ÷ 40 MHz = 25 ns
(This SCSI synchronous core clock is determined in
SCNTL3 bits [6:4], ExtCC = 1 if SCNTL1 bit 7 is asserted
and the SYM53C896 is sending data. ExtCC = 0 if the
SYM53C896 is receiving data.)
SXFERP = 100 ÷ 25 = 4
Where
SXFERP Synchronous transfer period
SSCP
SSCF
ExtCC
SCSI synchronous core period
SCSI synchronous core frequency
Extra clock cycle of data setup
4-34
Registers
Table 4.3
Examples of Synchronous Transfer
Periods and Rates for SCSI-1
Synch.
Transfer
Rate
SCSI CLK
÷ SCNTL3
Synch.
Transfer
CLK (MHz) Bits [6:4]
XFERP Period (ns) (Mbytes)
66.67
66.67
50
3
3
4
5
4
5
4
4
4
4
4
4
180
225
160
200
200
160
180
160
200
240
5.55
4.44
6.25
5
2
5
2
40
4
5
37.50
33.33
25
1.5
1.5
1
6.25
5.55
6.25
5
20
1
16.67
1
4.17
Table 4.4
Example Transfer Periods and Rates for
Fast SCSI-2, Ultra and Ultra2
Synch.
Transfer
Rate
SCSI CLK
÷ SCNTL3
Synch.
Transfer
CLK (MHz) Bits [6:4]
XFERP Period (ns) (Mbytes)
160
160
160
80
1
2
4
1
1
1
1
1
1
1
1
1
4
4
4
4
4
4
4
4
4
4
4
4
25
50
40
20
100
50
10
20
50
80
12.5
10.0
10.0
9.375
8.33
6.25
5
50
100
100
106.67
120
160
200
240
40
37.50
33.33
25
20
16.67
4.17
SCSI Registers
4-35
MO[4:0]
Max SCSI Synchronous Offset
[4:0]
These bits describe the maximum SCSI synchronous
offset used by the SYM53C896 SCSI function when
transferring synchronous SCSI data in either the initiator
or target mode. The following table describes the possible
combinations and their relationship to the synchronous
data offset used by the SYM53C896 SCSI function.
These bits determine the SYM53C896 SCSI function’s
method of transfer for Data In and Data Out phases only.
All other information transfers occur asynchronously.
4-36
Registers
Table 4.5
Maximum Synchronous Offset
MO4 MO3 MO2 MO1 MO0 Synchronous Offset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0-Asynchronous
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
SCSI Registers
4-37
Register: 0x06
SCSI Destination ID (SDID)
Read/Write
7
4
x
3
0
0
0
R
ENC[3:0]
x
x
x
0
0
R
Reserved
[7:4]
[3:0]
ENC[3:0]
Encoded Destination SCSI ID
Writing these bits sets the SCSI ID of the intended
initiator or target during SCSI reselection or selection
phases, respectively. When executing SCRIPTS, the
SCRIPTS processor writes the destination SCSI ID to
this register. The SCSI ID is defined by the user in a
SCRIPTS Select or Reselect instruction. The value
written is the binary-encoded ID. The priority of the 16
possible IDs, in descending order, is:
Highest
Lowest
7
6
5
4
3
2
1
0 15 14 13 12 11 10 9
8
Register: 0x07
General Purpose (GPREG)
Read/Write
7
x
5
x
4
0
0
x
R
x
GPIO
x
x
x
This register complements the GPREG register in the other SCSI
function. Any reads or writes to either of these registers have the same
effect, and are reflected in both registers. Reads to these two registers
will always yield the same values. A write to this register will cause the
data written to be output to the appropriate GPIO pin if it is set to output
mode in that function’s General Purpose Pin Control (GPCNTL) register.
Behavior of GPIO pins, if set to output mode by both functions, is
undefined.
4-38
Registers
R
Reserved
[7:5]
[4:0]
GPIO
General Purpose I/O
These bits are programmed through the General Purpose
Pin Control (GPCNTL) register as inputs, outputs, or to
perform special functions. As an output, these pins can
be used to enable or disable external terminators. It is
also possible to program these signals as live inputs and
sense them through a SCRIPTS register to register Move
Instruction. GPIO[3:0] default as inputs and GPIO4
defaults as an output pin. When configured as inputs, an
internal pull-down is enabled.
LSI Logic Symbios software uses the GPIO[1:0] signals
to access serial EEPROM. GPIO1 is used as a clock,
with the GPIO0 pin serving as data.
LSI Logic Symbios software also reserves the use of
GPIO[4:2]. If there is a need to use GPIO[4:2], please
check with LSI Logic for additional information.
Register: 0x08
SCSI First Byte Received (SFBR)
Read/Write
7
0
0
IB
0
0
0
0
0
0
0
This register contains the first byte received in any asynchronous
information transfer phase. For example, when a SYM53C896 SCSI
function is operating in the initiator mode, this register contains the first
byte received in the Message-In, Status, and Data-In phases.
When a Block Move instruction is executed for a particular phase, the
first byte received is stored in this register - even if the present phase is
the same as the last phase. The first byte received value for a particular
input phase is not valid until after a MOVE instruction is executed.
This register is also the accumulator for register read-modify-writes with
the SCSI First Byte Received (SFBR) as the destination. This allows bit
testing after an operation.
SCSI Registers
4-39
The SCSI First Byte Received (SFBR) is not writable using the CPU, and
therefore not by a Memory Move. However, it can be loaded using
SCRIPTS Read/Write operations. To load the SFBR with a byte stored
in system memory, the byte must first be moved to an intermediate
SYM53C896 SCSI function register (such as the SCRATCH register),
and then to the SFBR.
This register also contains the state of the lower eight bits of the SCSI
data bus during the Selection phase if the COM bit in the DMA Control
(DCNTL) register is clear.
If the COM bit is cleared, do not access this register using SCRIPTS
operations, as nondeterminate operations may occur. (This includes
SCRIPTS Read/Write operations and conditional transfer control
instructions that initialize the SCSI First Byte Received (SFBR) register.)
Register: 0x09
SCSI Output Control Latch (SOCL)
Read/Write
7
REQ
0
6
ACK
0
5
BSY
0
4
SEL
0
3
ATN
0
2
MSG
0
1
C_D
0
0
I/O
0
REQ
Assert SCSI REQ/ Signal
Assert SCSI ACK/ Signal
Assert SCSI BSY/ Signal
Assert SCSI SEL/ Signal
Assert SCSI ATN/ Signal
Assert SCSI MSG/ Signal
Assert SCSI C_D/ Signal
Assert SCSI I_O/ Signal
7
6
5
4
3
2
1
0
ACK
BSY
SEL
ATN
MSG
C_D
I/O
This register is used primarily for diagnostic testing or programmed I/O
operation. It is controlled by the SCRIPTS processor when executing
SCSI SCRIPTS. SCSI Output Control Latch (SOCL) is used only when
transferring data using programmed I/O. Some bits are set or cleared
4-40
Registers
when executing SCSI SCRIPTS. Do not write to the register once the
SYM53C896 SCSI function starts executing normal SCSI SCRIPTS.
Register: 0x0A
SCSI Selector ID (SSID)
Read Only
7
VAL
0
6
4
0
3
0
0
0
R
0
ENID
0
0
0
VAL
SCSI Valid
7
If VAL is asserted, then the two SCSI IDs are detected
on the bus during a bus-initiated selection or reselection,
and the encoded destination SCSI ID bits below are valid.
If VAL is deasserted, only one ID is present and the
contents of the encoded destination ID are meaningless.
R
Reserved
[6:4]
ENID
Encoded Destination SCSI ID
[3:0]
Reading the SCSI Selector ID (SSID) register immediately
after the SYM53C896 SCSI function is selected or
reselected returns the binary-encoded SCSI ID of the
device that performed the operation. These bits are
invalid for targets that are selected under the single
initiator option of the SCSI-1 specification. This condition
is detected by examining the VAL bit.
SCSI Registers
4-41
Register: 0x0B
SCSI Bus Control Lines (SBCL)
Read Only
7
REQ
x
6
ACK
x
5
BSY
x
4
SEL
x
3
ATN
x
2
MSG
x
1
C_D
x
0
I_O
x
REQ
Assert SCSI REQ/ Signal
Assert SCSI ACK/ Signal
Assert SCSI BSY/ Signal
Assert SCSI SEL/ Signal
Assert SCSI ATN/ Signal
Assert SCSI MSG/ Signal
Assert SCSI C_D/ Signal
Assert SCSI I_O/ Signal
7
6
5
4
3
2
1
0
ACK
BSY
SEL
ATN
MSG
C_D
I_O
This register returns the SCSI control line status. A bit is set when the
corresponding SCSI control line is asserted. These bits are not latched;
they are a true representation of what is on the SCSI bus at the time the
register is read. The resulting read data is synchronized before being
presented to the PCI bus to prevent parity errors from being passed to
the system. This register is used for diagnostic testing or operation in the
low level mode.
Register: 0x0C
DMA Status (DSTAT)
Read Only
7
DFE
1
6
MDPE
0
5
BF
0
4
ABRT
0
3
SSI
0
2
SIR
0
1
R
x
0
IID
0
Reading this register clears any bits that are set at the time the register
is read, but does not necessarily clear the register in case additional
interrupts are pending (the SYM53C896 SCSI functions stack interrupts).
4-42
Registers
The DIP bit in the Interrupt Status Zero (ISTAT0) register is also cleared.
It is possible to mask DMA interrupt conditions individually through the
DMA Interrupt Enable (DIEN) register.
When performing consecutive 8-bit reads of the DMA Status (DSTAT),
SCSI Interrupt Status Zero (SIST0) and SCSI Interrupt Status One (SIST1)
registers (in any order), insert a delay equivalent to 12 CLK periods
between the reads to ensure that the interrupts clear properly. See
Chapter 2, “Functional Description” for more information on interrupts.
DFE
DMA FIFO Empty
7
This status bit is set when the DMA FIFO is empty. It is
possible to use it to determine if any data resides in the
FIFO when an error occurs and an interrupt is generated.
This bit is a pure status bit and does not cause an
interrupt.
MDPE
Master Data Parity Error
6
This bit is set when the SYM53C896 SCSI function as a
master detects a data parity error, or a target device
signals a parity error during a data phase. This bit is
completely disabled by the Master Parity Error Enable bit
(bit 3 of Chip Test Four (CTEST4)).
BF
Bus Fault
5
This bit is set when a PCI bus fault condition is detected.
A PCI bus fault can only occur when the SYM53C896
SCSI function is bus master, and is defined as a cycle
that ends with a Bad Address or Target Abort Condition.
ABRT
Aborted
4
This bit is set when an abort condition occurs. An abort
condition occurs when a software abort command is
issued by setting bit 7 of the Interrupt Status Zero (ISTAT0)
register.
SSI
SIR
Single Step Interrupt
3
If the Single Step Mode bit in the DMA Control (DCNTL)
register is set, this bit is set and an interrupt generated
after successful execution of each SCRIPTS instruction.
SCRIPTS Interrupt Instruction Received
This status bit is set whenever an interrupt instruction is
evaluated as true.
2
SCSI Registers
4-43
R
Reserved
1
0
IID
Illegal Instruction Detected
This status bit is set any time an illegal or reserved
instruction opcode is detected, whether the SYM53C896
SCSI function is operating in single step mode or
automatically executing SCSI SCRIPTS.
Any of the following conditions during instruction
execution also sets this bit:
•
•
•
The SYM53C896 SCSI function is executing a Wait
Disconnect instruction and the SCSI REQ line is
asserted without a disconnect occurring.
A Block Move instruction is executed with 0x000000
loaded into the DMA Byte Counter (DBC) register,
indicating there are zero bytes to move.
During a Transfer Control instruction, the Compare
Data (bit 18) and Compare Phase (bit 17) bits are set
in the DMA Byte Counter (DBC) register while the
SYM53C896 SCSI function is in target mode.
•
During a Transfer Control instruction, the Carry Test
bit (bit 21) is set and either the Compare Data (bit 18)
or Compare Phase (bit 17) bit is set.
•
•
A Transfer Control instruction is executed with the
reserved bit 22 set.
A Transfer Control instruction is executed with the
Wait for Valid phase bit (bit 16) set while the chip is in
target mode.
•
A Load/Store instruction is issued with the memory
address mapped to the operating registers of the chip,
not including ROM or RAM.
•
•
A Load/Store instruction is issued when the register
address is not aligned with the memory address.
A Load/Store instruction is issued with bit 5 in the
DMA Command (DCMD) register cleared or bits 3 or 2
set.
•
•
A Load/Store instruction when the count value in the
DMA Byte Counter (DBC) register is not set at 1 to 4.
A Load/Store instruction attempts to cross a dword
boundary.
4-44
Registers
•
•
A Memory Move instruction is executed with one of
the reserved bits in the DMA Command (DCMD)
register set.
A Memory Move instruction is executed with the
source and destination addresses not aligned.
Register: 0x0D
SCSI Status Zero (SSTAT0)
Read Only
7
ILF
0
6
ORF
0
5
OLF
0
4
AIP
0
3
LOA
0
2
WOA
0
1
RST
0
0
SDP0
0
ILF
SIDL Least Significant Byte Full
7
This bit is set when the least significant byte in the SCSI
Input Data Latch (SIDL) contains data. Data is transferred
from the SCSI bus to the SCSI Input Data Latch register
before being sent to the DMA FIFO and then to the host
bus. The SCSI Input Data Latch (SIDL) register contains
SCSI data received asynchronously. Synchronous data
received does not flow through this register.
ORF
SODR Least Significant Byte Full
6
This bit is set when the least significant byte in the SCSI
Output Data Register (SODR, a hidden buffer register
which is not accessible) contains data. The SODR is
used by the SCSI logic as a second storage register
when sending data synchronously. It is not readable or
writable by the user. It is possible to use this bit to
determine how many bytes reside in the chip when an
error occurs.
OLF
SODL Least Significant Byte Full
5
This bit is set when the least significant byte in the SCSI
Output Data Latch (SODL) contains data. The SODL
register is the interface between the DMA logic and the
SCSI bus. In synchronous mode, data is transferred from
the host bus to the SCSI Output Data Latch (SODL)
register, and then to the SCSI Output Data Register
(SODR, a hidden buffer register which is not accessible)
before being sent to the SCSI bus. In asynchronous
mode, data is transferred from the host bus to the SODL
SCSI Registers
4-45
register, and then to the SCSI bus. The SODR buffer
register is not used for asynchronous transfers. It is
possible to use this bit to determine how many bytes
reside in the chip when an error occurs.
AIP
Arbitration in Progress
4
Arbitration in Progress (AIP = 1) indicates that the
SYM53C896 SCSI function has detected a Bus Free
condition, asserted SBSY, and asserted its SCSI ID onto
the SCSI bus.
LOA
WOA
Lost Arbitration
3
When set, LOA indicates that the SYM53C896 SCSI
function has detected a bus free condition, arbitrated for
the SCSI bus, and lost arbitration due to another SCSI
device asserting the SSEL/ signal.
Won Arbitration
2
When set, WOA indicates that the SYM53C896 SCSI
function has detected a Bus Free condition, arbitrated for
the SCSI bus and won arbitration. The arbitration mode
selected in the SCSI Control Zero (SCNTL0) register must
be full arbitration and selection to set this bit.
RST
SCSI RST/ Signal
1
This bit reports the current status of the SCSI RST/
signal, and the RST signal (bit 3) in the SCSI Control One
(SCNTL1) register. This bit is not latched and may change
as it is read.
SDP0
SCSI SDP0 Parity Signal
0
This bit represents the present state of the SCSI SDP0/
parity signal. This signal is not latched and may change
as it is read.
4-46
Registers
Register: 0x0E
SCSI Status One (SSTAT1)
Read Only
7
4
0
3
SDP0L
x
2
MSG
x
1
C_D
x
0
I/O
x
FF[3:0]
0
0
0
FF[3:0]
FIFO Flags
[7:4]
These four bits, along with SCSI Status Two (SSTAT2)
bit 4, define the number of bytes or words that currently
reside in the SYM53C896’s SCSI synchronous data
FIFO. These bits are not latched and they will change as
data moves through the FIFO.
SCSI Registers
4-47
Table 4.6
SCSI Synchronous Data FIFO Word
Count
Bytes or
Words in the
SCSI FIFO
FF4
(SSTAT2 bit 4) FF3
FF2
FF1
FF0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
4-48
Registers
SDP0L
Latched SCSI Parity
3
This bit reflects the SCSI parity signal (SDP0/),
corresponding to the data latched in the SCSI Input Data
Latch (SIDL). It changes when a new byte is latched into
the least significant byte of the SIDL register. This bit is
active high, in other words, it is set when the parity signal
is active.
MSG
C_D
I/O
SCSI MSG/ Signal
SCSI C_D/ Signal
2
1
0
SCSI I_O/ Signal
These SCSI phase status bits are latched on the
asserting edge of SREQ/ when operating in either the
initiator or target mode. These bits are set when the
corresponding signal is active. They are useful when
operating in the low level mode.
Register: 0x0F
SCSI Status Two (SSTAT2)
Read Only
7
ILF
0
6
ORF1
0
5
OLF1
0
4
FF4
0
3
SPL1
x
2
DIFF
x
1
LDSC
1
0
SDP1
x
ILF
SIDL Most Significant Byte Full
7
This bit is set when the most significant byte in the SCSI
Input Data Latch (SIDL) contains data. Data is transferred
from the SCSI bus to the SCSI Input Data Latch register
before being sent to the DMA FIFO and then to the host
bus. The SIDL register contains SCSI data received
asynchronously. Synchronous data received does not
flow through this register.
ORF1
SODR Most Significant Byte Full
6
This bit is set when the most significant byte in the SCSI
Output Data Register (SODR, a hidden buffer register
which is not accessible) contains data. The SODR
register is used by the SCSI logic as a second storage
register when sending data synchronously. It is not
accessible to the user. This bit is used to determine how
many bytes reside in the chip when an error occurs.
SCSI Registers
4-49
OLF1
SODL Most Significant Byte Full
5
This bit is set when the most significant byte in the SCSI
Output Data Latch (SODL) contains data. The SODL
register is the interface between the DMA logic and the
SCSI bus. In synchronous mode, data is transferred from
the host bus to the SODL register, and then to the SCSI
Output Data Register (SODR, a hidden buffer register
which is not accessible) before being sent to the SCSI
bus. In asynchronous mode, data is transferred from the
host bus to the SCSI Output Data Latch (SODL) register,
and then to the SCSI bus. The SODR buffer register is
not used for asynchronous transfers. It is possible to use
this bit to determine how many bytes reside in the chip
when an error occurs.
FF4
FIFO Flags, Bit 4
4
This is the most significant bit in the SCSI FIFO Flags
field, with the rest of the bits in SCSI Status One
(SSTAT1). For a complete description of this field, see the
definition for SSTAT1 bits [7:4].
SPL1
DIFF
Latched SCSI parity for SD[15:8]
3
This active HIGH bit reflects the SCSI odd parity signal
corresponding to the data latched into the most
significant byte in the SCSI Input Data Latch (SIDL)
register.
Diffsens Mismatch
2
This bit is set when the DIFFSENS pin detects a SE or
LVD SCSI operating voltage level while the SYM53C896
is operating in HVD mode (by setting the DIF bit in the
SCSI Test Two (STEST2) register). If this bit is cleared, the
DIFFSENS value matches the DIF bit setting.
LDSC
Last Disconnect
1
This bit is used in conjunction with the Connected (CON)
bit in SCSI Control One (SCNTL1). It allows the user to
detect the case in which a target device disconnects, and
then some SCSI device selects or reselects the
SYM53C896 SCSI function. If the Connected bit is
asserted and the LDSC bit is asserted, a disconnect is
indicated. This bit is set when the Connected bit in
SCNTL1 is off. This bit is cleared when a Block Move
instruction is executed while the Connected bit in
SCNTL1 is on.
4-50
Registers
SDP1
SCSI SDP1 Parity Signal
0
This bit represents the present state of the SCSI SDP1/
parity signal. It is unlatched and may change as it is read.
Registers:0x10–0x13
Data Structure Address (DSA)
Read/Write
This 32-bit register contains the base address used for all table indirect
calculations. The DSA register is usually loaded prior to starting an I/O,
but it is possible for a SCRIPTS Memory Move to load the DSA during
the I/O.
During any Memory-to-Memory Move operation, the contents of this
register is preserved. The power-up value of this register is
indeterminate.
Register: 0x14
Interrupt Status Zero (ISTAT0)
Read/Write
7
ABRT
0
6
SRST
0
5
SIGP
0
4
SEM
0
3
CON
0
2
INTF
0
1
SIP
0
0
DIP
0
This is the only register that is accessible by the host CPU while a
SYM53C896 SCSI function is executing SCRIPTS (without interfering in
the operation of the function). It is used to poll for interrupts if hardware
interrupts are disabled. Read this register after servicing an interrupt to
check for stacked interrupts.
ABRT
Aborted
7
Setting this bit aborts the current operation under
execution by the SYM53C896 SCSI function. If this bit is
set and an interrupt is received, clear this bit before
reading the DMA Status (DSTAT) register to prevent
further aborted interrupts from being generated. The
sequence to abort any operation is:
1. Set this bit.
2. Wait for an interrupt.
3. Read the Interrupt Status Zero (ISTAT0) register.
SCSI Registers
4-51
4. If the SCSI Interrupt Pending bit is set, then read the
SCSI Interrupt Status Zero (SIST0) or SCSI Interrupt
Status One (SIST1) register to determine the cause of
the SCSI Interrupt and go back to step 2.
5. If the SCSI Interrupt Pending bit is clear, and the DMA
Interrupt Pending bit is set, then write 0x00 value to
this register.
6. Read the DMA Status (DSTAT) register to verify the
aborted interrupt and to see if any other interrupting
conditions have occurred.
SRST
Software Reset
6
Setting this bit resets the SYM53C896 SCSI function. All
operating registers are cleared to their respective default
values and all SCSI signals are deasserted. Setting this
bit does not assert the SCSI RST/ signal. This reset does
not clear the ID Mode bit or any of the PCI configuration
registers. This bit is not self-clearing; it must be cleared
to clear the reset condition (a hardware reset also clears
this bit).
SIGP
Signal Process
5
SIGP is a R/W bit that is writable at any time, and polled
and reset using Chip Test Two (CTEST2). The SIGP bit is
used in various ways to pass a flag to or from a running
SCRIPTS instruction.
The only SCRIPTS instruction directly affected by the
SIGP bit is Wait For Selection/Reselection. Setting this bit
causes that instruction to jump to the alternate address
immediately. The instructions at the alternate jump
address should check the status of SIGP to determine
the cause of the jump. The SIGP bit is usable at any time
and is not restricted to the wait for selection/reselection
condition.
SEM
Semaphore
4
The SCRIPTS processor may set this bit using a
SCRIPTS register write instruction. An external processor
may also set it while the SYM53C896 SCSI function is
executing a SCRIPTS operation. This bit enables the
SCSI function to notify an external processor of a
predefined condition while SCRIPTS are running. The
4-52
Registers
external processor may also notify the SYM53C896 SCSI
function of a predefined condition and the SCRIPTS
processor may take action while SCRIPTS are executing.
CON
Connected
3
This bit is automatically set any time the SYM53C896
SCSI function is connected to the SCSI bus as an initiator
or as a target. It is set after successfully completing
selection or when the SYM53C896 SCSI function
responds to a bus-initiated selection or reselection. It is
also set after the SCSI function wins arbitration when
operating in low level mode. When this bit is cleared, the
SYM53C896 SCSI function is not connected to the SCSI
bus.
INTF
Interrupt-on-the-Fly
2
This bit is asserted by an INTFLY instruction during
SCRIPTS execution. SCRIPTS programs do not halt
when the interrupt occurs. This bit can be used to notify
a service routine, running on the main processor while
the SCRIPTS processor is still executing a SCRIPTS
program. If this bit is set, when the Interrupt Status Zero
(ISTAT0) register is read it is not automatically cleared. To
clear this bit, write it to a one. The reset operation is
self-clearing.
Note:
If the INTF bit is set but SIP or DIP is not set, do not
attempt to read the other chip status registers. An
interrupt-on-the-fly must be cleared before servicing any
other interrupts indicated by SIP or DIP.
This bit must be written to one in order to clear it after it
has been set.
SCSI Registers
4-53
SIP
SCSI Interrupt Pending
1
This status bit is set when an interrupt condition is
detected in the SCSI portion of the SYM53C896 SCSI
function. The following conditions cause a SCSI interrupt
to occur:
•
A phase mismatch (initiator mode) or SATN/ becomes
active (target mode)
•
•
•
•
•
•
•
•
•
•
An arbitration sequence completes
A selection or reselection time-out occurs
The SYM53C896 SCSI function is selected
The SYM53C896 SCSI function is reselected
A SCSI gross error occurs
An unexpected disconnect occurs
A SCSI reset occurs
A parity error is detected
The handshake-to-handshake timer is expired
The general purpose timer is expired
To determine exactly which condition(s) caused the
interrupt, read the SCSI Interrupt Status Zero (SIST0) and
SCSI Interrupt Status One (SIST1) registers.
DIP
DMA Interrupt Pending
0
This status bit is set when an interrupt condition is
detected in the DMA portion of the SYM53C896 SCSI
function. The following conditions cause a DMA interrupt
to occur:
•
•
•
•
A PCI parity error is detected
A bus fault is detected
An abort condition is detected
A SCRIPTS instruction is executed in single step
mode
•
•
A SCRIPTS interrupt instruction is executed
An illegal instruction is detected
To determine exactly which condition(s) caused the
interrupt, read the DMA Status (DSTAT) register.
4-54
Registers
Register: 0x15
Interrupt Status One (ISTAT1)
Read/Write
7
3
x
2
FLSH
0
1
SRUN
0
0
SI
0
R
x
x
x
x
R
Reserved
Flushing
[7:3]
FLSH
2
Reading this bit monitors if the chip is currently flushing
data. If set, the chip is flushing data from the DMA FIFO.
If cleared, no flushing is occurring. This bit is read only
and writes will have no effect on the value of this bit.
SRUN
SCRIPTS Running
1
This bit indicates whether or not the SCRIPTS engine is
currently fetching and executing SCRIPTS instructions. If
this bit is set, the SCRIPTS engine is active.
If it is cleared, the SCRIPTS engine is not active.
This bit is read only and writes will have no effect on the
value of this bit.
SI
SYNC_IRQD
0
Setting this bit disables the INTA/ pin for Function A and
the INTB/ pin for Function B. Clearing this bit enables
normal operation of the INTA/ (or INTB/) pin. The function
of this bit is nearly identical to bit 1 of DMA Control
(DCNTL) (Register 0x3B) except that if the INTA/ (or
INTB/) is already asserted and this bit is set, INT will
remain asserted until the interrupt is serviced. At this
point the interrupt line will be blocked for future interrupts
until this bit is cleared. In addition, this bit may be read
and written while SCRIPTS are executing.
SCSI Registers
4-55
Register: 0x16
Mailbox Zero (MBOX0)
Read/Write
7
0
0
MBOX0
0
0
0
0
0
0
0
MBOX0
Mailbox Zero
[7:0]
These are general purpose bits that may be read or
written while SCRIPTS are running. They also may be
read or written by the SCRIPTS processor.
Note:
The host and the SCRIPTS processor code could
potentially attempt to access the same mailbox byte at the
same time. Using one mailbox register as a read only and
the other as a write only will prevent this type of conflict.
Register: 0x17
Mailbox One (MBOX1)
Read/Write
7
0
0
MBOX1
0
0
0
0
0
0
0
MBOX1
Mailbox One
[7:0]
These are general purpose bits that may be read or
written while SCRIPTS are running. They also may be
read or written by the SCRIPTS processor.
Note:
The host and the SCRIPTS processor code could
potentially attempt to access the same mailbox byte at the
same time. Using one mailbox register as a read only and
the other as a write only will prevent this type of conflict.
4-56
Registers
Register: 0x18
Chip Test Zero (CTEST0)
Read/Write
7
0
1
FMT
1
1
1
1
1
1
1
FMT
Byte Empty in DMA FIFO
[7:0]
These bits identify the bottom bytes in the DMA FIFO that
are empty. Each bit corresponds to a byte lane in the
DMA FIFO. For example, if byte lane three is empty, then
FMT3 will be set. Since the FMT flags indicate the status
of bytes at the bottom of the FIFO, if all FMT bits are set,
the DMA FIFO is empty.
Register: 0x19
Chip Test One (CTEST1)
Read Only
7
0
0
FFL
0
0
0
0
0
0
0
FFL
Byte Full in DMA FIFO
[7:0]
These status bits identify the top bytes in the DMA FIFO
that are full. Each bit corresponds to a byte lane in the
DMA FIFO. For example, if byte lane three is full then
FFL3 is set. Since the FFL flags indicate the status of
bytes at the top of the FIFO, if all FFL bits are set, the
DMA FIFO is full.
SCSI Registers
4-57
Register: 0x1A
Chip Test Two (CTEST2)
Read Only (bit 3 write)
7
DDIR
0
6
SIGP
0
5
CIO
x
4
CM
x
3
PCICIE
0
2
TEOP
0
1
DREQ
0
0
DACK
1
DDIR
Data Transfer Direction
7
This status bit indicates which direction data is being
transferred. When this bit is set, the data is transferred
from the SCSI bus to the host bus. When this bit is clear,
the data is transferred from the host bus to the SCSI bus.
SIGP
Signal Process
6
This bit is a copy of the SIGP bit in the Interrupt Status
Zero (ISTAT0) register (bit 5). The SIGP bit is used to
signal a running SCRIPTS instruction. When this register
is read, the SIGP bit in the ISTAT0 register is cleared.
CIO
CM
Configured as I/O
5
This bit is defined as the Configuration I/O Enable Status
bit. This read only bit indicates if the chip is currently
enabled as I/O space.
Configured as Memory
4
This bit is defined as the configuration memory enable
status bit. This read only bit indicates if the chip is
currently enabled as memory space.
Note:
Bits 4 and 5 may be set if the chip is mapped in both I/O
and memory space. Also, bits 4 and 5 may be set if the chip
is dual-mapped.
PCICIE
PCI Configuration Info Enable
3
This bit controls the shadowing of the PCI Base Address
Register Two (SCRIPTS RAM), PCI Base Address
Register One (MEMORY), PCI Device ID, and PCI
Revision ID (Rev ID) into the Scratch Register A
(SCRATCHA), Memory Move Read Selector (MMRS),
Scratch Register B (SCRATCHB), Memory Move Write
Selector (MMWS), and SCRIPTS Fetch Selector (SFS)
registers.
4-58
Registers
When it is set, MMWS contains bits [63:32] and
SCRATCH B contains bits [31:0] of the RAM Base
Address value from the PCI Configuration Base Address
Register Two (SCRIPTS RAM).
This is the base address for the internal 8 Kbytes internal
RAM. Memory Move Read Selector (MMRS) contains bits
[63:32] and Scratch Register A (SCRATCHA) contains bits
[31:0] of the memory mapped operating register base
address. Bits [23:16] of SCRIPTS Fetch Selector (SFS)
contain the PCI Revision ID (Rev ID) register value and
bits [15:0] contain the PCI Device ID register value. When
this bit is set, only reads to the registers are affected,
writes will pass through normally.
When this bit is cleared, the SCRATCH A, MMRS,
SCRATCH B, MMWS, and SFS registers return to normal
operation.
Note:
Bit 3 is the only writable bit in this register. All other bits are
read only. When modifying this register, all other bits must
be written to zero. Do not execute a Read-Modify-Write to
this register.
TEOP
SCSI True End of Process
2
This bit indicates the status of the SYM53C896 SCSI
function’s internal TEOP signal. The TEOP signal
acknowledges the completion of a transfer through the
SCSI portion of the SYM53C896 SCSI function. When
this bit is set, TEOP is active. When this bit is cleared,
TEOP is inactive.
DREQ
DACK
Data Request Status
1
0
This bit indicates the status of the SYM53C896 SCSI
function’s internal Data Request signal (DREQ). When
this bit is set, DREQ is active. When this bit is cleared,
DREQ is inactive.
Data Acknowledge Status
This bit indicates the status of the SYM53C896 SCSI
function’s internal Data Acknowledge signal (DACK/).
When this bit is set, DACK/ is inactive. When this bit is
cleared, DACK/ is active.
SCSI Registers
4-59
Register: 0x1B
Chip Test Three (CTEST3)
Read/Write
7
4
x
3
FLF
0
2
CLF
0
1
FM
0
0
WRIE
1
V
x
x
x
V
Chip Revision Level
[7:4]
These bits identify the chip revision level for software
purposes. It should have the same value as the lower
nibble of the PCI Revision ID (Rev ID) register. These bits
are read only.
FLF
Flush DMA FIFO
3
When this bit is set, data residing in the DMA FIFO is
transferred to memory, starting at the address in the DMA
Next Address (DNAD) register. The internal DMAWR
signal, controlled by the Chip Test Five (CTEST5) register,
determines the direction of the transfer. This bit is not
self-clearing; clear it once the data is successfully
transferred by the SYM53C896 SCSI function.
Note:
Polling of FIFO flags is allowed during flush operations.
CLF
Clear DMA FIFO
2
When this bit is set, all data pointers for the DMA FIFO
are cleared. Any data in the FIFO is lost. After the
SYM53C896 SCSI function successfully clears the
appropriate FIFO pointers and registers, this bit
automatically clears.
Note:
This bit does not clear the data visible at the bottom of the
FIFO.
FM
Fetch Pin Mode
1
When set, this bit causes the FETCH/ pin to deassert
during indirect and table indirect read operations.
FETCH/ is only active during the opcode portion of an
instruction fetch. This allows the storage of SCRIPTS in
a PROM while data tables are stored in RAM.
If this bit is not set, FETCH/ is asserted for all bus cycles
during instruction fetches.
4-60
Registers
WRIE
Write and Invalidate Enable
0
This bit, when set, causes the issuing of Write and
Invalidate commands on the PCI bus whenever legal.
The Write and Invalidate Enable bit in the PCI
Configuration Command register must also be set in
order for the chip to generate Write and Invalidate
commands.
Registers:0x1C–0x1F
Temporary (TEMP)
Read/Write
This 32-bit register stores the Return instruction address pointer from the
Call instruction. The address pointer stored in this register is loaded into
the DMA SCRIPTS Pointer (DSP) register when a Return instruction is
executed. This address points to the next instruction to execute. Do not
write to this register while the SYM53C896 SCSI function is executing
SCRIPTS.
During any Memory-to-Memory Move operation, the contents of this
register are preserved. The power-up value of this register is
indeterminate.
Register: 0x20
DMA FIFO (DFIFO)
Read/Write
7
0
0
1
BO
0
0
0
0
0
0
BO
Byte Offset Counter
[7:0]
These bits, along with bits [1:0] in the Chip Test Five
(CTEST5) register, indicate the amount of data
transferred between the SCSI core and the DMA core. It
is used to determine the number of bytes in the DMA
FIFO when an interrupt occurs. These bits are unstable
while data is being transferred between the two cores.
Once the chip has stopped transferring data, these bits
are stable.
The DMA FIFO (DFIFO) register counts the number of
bytes transferred between the DMA core and the SCSI
SCSI Registers
4-61
core. The DMA Byte Counter (DBC) register counts the
number of bytes transferred across the host bus. The
difference between these two counters represents the
number of bytes remaining in the DMA FIFO.
The following steps determine how many bytes are left in
the DMA FIFO when an error occurs, regardless of the
transfer direction:
If the DFS bit (bit 5, Chip Test Five (CTEST5)) is set:
Step 1. Subtract the ten least significant bits of the DMA
Byte Counter (DBC) register from the 10-bit value
of the DFBOC which is made up of the Chip Test
Five (CTEST5) register (bits [1:0]) and the DMA
FIFO (DFIFO) register (bits [7:0]).
Step 2. AND the result with 0x3FF for a byte count
between zero and 944.
If the DFS bit (bit 5, Chip Test Five (CTEST5)) is cleared:
Step 1. Subtract the seven least significant bits of the
DMA Byte Counter (DBC) register from the seven
bit value of the DFBOC which is made up of the
DMA FIFO (DFIFO) register (bits [6:0]).
Step 2. AND the result with 0x7F for a byte count
between zero and 112.
Note:
If trying to calculate the total number of bytes in both the
DMA FIFO and SCSI Logic, see Section 2.2.12.1, “Data
Paths” in Chapter 2, “Functional Description”.
Register: 0x21
Chip Test Four (CTEST4)
Read/Write
7
BDIS
0
6
FBL3
0
5
ZSD
0
4
SRTM
0
3
MPEE
0
2
0
0
0
FBL[2:0]
0
BDIS
Burst Disable
7
When set, this bit causes the SYM53C896 SCSI function
to perform back to back cycles for all transfers. When this
4-62
Registers
bit is cleared, back to back transfers for opcode fetches
and burst transfers for data moves are performed.
FBL3
ZSD
FIFO Byte Control
This bit is used with FBL[2:0]. See Bits [2:0] description
in this register.
6
SCSI Data High Impedance
5
Setting this bit causes the SYM53C896 SCSI function to
place the SCSI data bus SD[15:0] and the parity lines
SDP[1:0] in a high impedance state. In order to transfer
data on the SCSI bus, clear this bit.
SRTM
Shadow Register Test Mode
4
Setting this bit allows access to the shadow registers
used by Memory-to-Memory Move operations. When this
bit is set, register accesses to the Temporary (TEMP) and
Data Structure Address (DSA) registers are directed to the
shadow copies STEMP (Shadow TEMP) and SDSA
(Shadow DSA). The registers are shadowed to prevent
them from being overwritten during a Memory-to-Memory
Move operation. The Data Structure Address (DSA) and
Temporary (TEMP) registers contain the base address
used for table indirect calculations, and the address
pointer for a call or return instruction, respectively. This bit
is intended for manufacturing diagnostics only and should
not be set during normal operations.
MPEE
Master Parity Error Enable
3
Setting this bit enables parity checking during master
data phases. A parity error during a bus master read is
detected by the SYM53C896 SCSI function. A parity error
during a bus master write is detected by the target, and
the SYM53C896 SCSI function is informed of the error by
the PERR/ pin being asserted by the target. When this bit
is cleared, the SYM53C896 SCSI function does not
interrupt if a master parity error occurs. This bit is cleared
at power-up.
SCSI Registers
4-63
FBL[2:0]
FIFO Byte Control
[2:0]
DMA FIFO
FBL3 FBL2 FBL1 FBL0 Byte Lane
Pins
0
1
1
1
1
1
1
1
1
X
0
0
0
0
1
1
1
1
X
0
0
1
1
0
0
1
1
X
0
1
0
1
0
1
0
1
Disabled
n/a
0
1
2
3
4
5
6
7
D[7:0]
D[15:8]
D[23:16]
D[31:24]
D[39:32]
D[47:40]
D[53:48]
D[63:54]
These bits steer the contents of the Chip Test Six
(CTEST6) register to the appropriate byte lane of the
64-bit DMA FIFO. If the FBL3 bit is set, then FBL2
through FBL0 determine which of eight byte lanes can be
read or written. When cleared, the byte lane read or
written is determined by the current contents of the DMA
Next Address (DNAD) and DMA Byte Counter (DBC)
registers. Each of the eight bytes that make up the 64-bit
DMA FIFO is accessed by writing these bits to the proper
value. For normal operation, FBL3 must equal zero.
Register: 0x22
Chip Test Five (CTEST5)
Read/Write
7
ADCK
0
6
BBCK
0
5
DFS
0
4
MASR
0
3
DDIR
0
2
BL2
0
1
0
0
0
BO[9:8]
ADCK
Clock Address Incrementor
7
Setting this bit increments the address pointer contained
in the DMA Next Address (DNAD) register. The DNAD
register is incremented based on the DNAD contents and
the current DMA Byte Counter (DBC) value. This bit
automatically clears itself after incrementing the DNAD
register.
4-64
Registers
BBCK
DFS
Clock Byte Counter
Setting this bit decrements the byte count contained in
the 24-bit DMA Byte Counter (DBC) register. It is
decremented based on the DBC contents and the current
DMA Next Address (DNAD) value. This bit automatically
clears itself after decrementing the DBC register.
6
DMA FIFO Size
5
This bit controls the size of the DMA FIFO. When clear,
the DMA FIFO appears as only 112 bytes deep. When
set, the DMA FIFO size increases to 944 bytes. Using an
112-byte FIFO allows software written for other
SYM53C8XX family chips to properly calculate the
number of bytes residing in the chip after a target
disconnect. The default value of this bit is zero.
MASR
DDIR
Master Control for Set or Reset Pulses
4
This bit controls the operation of bit 3. When this bit is
set, bit 3 asserts the corresponding signals. When this bit
is cleared, bit 3 deasserts the corresponding signals. Do
not change this bit and bit 3 in the same write cycle.
DMA Direction
3
Setting this bit either asserts or deasserts the internal
DMA Write (DMAWR) direction signal depending on the
current status of the MASR bit in this register. Asserting
the DMAWR signal indicates that data is transferred from
the SCSI bus to the host bus. Deasserting the DMAWR
signal transfers data from the host bus to the SCSI bus.
BL2
Burst Length Bit 2
2
This bit works with bits 6 and 7 (BL[1:0]) in the DMA
Mode (DMODE), 0x38 register to determine the burst
length. For complete definitions of this field, refer to the
descriptions of DMODE bits 6 and 7. This bit is disabled
if an 112-byte FIFO is selected by clearing the DMA FIFO
Size bit.
BO[9:8]
DMA FIFO Byte Offset Counter, Bits [9:8]
[1:0]
These are the upper two bits of the DFBOC. The DFBOC
consists of these bits and the DMA FIFO (DFIFO)
bits [7:0].
SCSI Registers
4-65
Register: 0x23
Chip Test Six (CTEST6)
Read/Write
7
0
0
DF[7:0]
0
0
0
0
0
0
0
DF[7:0]
DMA FIFO
[7:0]
Writing to this register writes data to the appropriate byte
lane of the DMA FIFO as determined by the FBL bits in
the Chip Test Four (CTEST4) register. Reading this
register unloads data from the appropriate byte lane of
the DMA FIFO as determined by the FBL bits in the
CTEST4 register. Data written to the FIFO is loaded into
the top of the FIFO. Data read out of the FIFO is taken
from the bottom. To prevent DMA data from being
corrupted, this register should not be accessed before
starting or restarting SCRIPTS operation. Write to this
register only when testing the DMA FIFO using the Chip
Test Four (CTEST4) register. Writing to this register while
the test mode is not enabled produces unexpected
results.
Registers:0x24–0x26
DMA Byte Counter (DBC)
Read/Write
This 24-bit register determines the number of bytes transferred in a Block
Move instruction. While sending data to the SCSI bus, the counter is
decremented as data is moved into the DMA FIFO from memory. While
receiving data from the SCSI bus, the counter is decremented as data is
written to memory from the SYM53C896 SCSI function. The DBC
counter is decremented each time data is transferred on the PCI bus. It
is decremented by an amount equal to the number of bytes that are
transferred.
The maximum number of bytes that can be transferred in any one Block
Move command is 16,777,215 bytes. The maximum value that can be
loaded into the DMA Byte Counter (DBC) register is 0xFFFFFF. If the
instruction is a Block Move and a value of 0x000000 is loaded into the
4-66
Registers
DBC register, an illegal instruction interrupt occurs if the SYM53C896
SCSI function is not in the target mode, Command phase.
The DMA Byte Counter (DBC) register is also used to hold the least
significant 24 bits of the first dword of a SCRIPTS fetch, and to hold the
offset value during table indirect I/O SCRIPTS. For a complete
description see Chapter 5, “SCSI SCRIPTS Instruction Set”. The
power-up value of this register is indeterminate.
Register: 0x27
DMA Command (DCMD)
Read/Write
This 8-bit register determines the instruction for the SYM53C896 SCSI
function to execute. This register has a different format for each
instruction. For a complete description see Chapter 5, “SCSI SCRIPTS
Instruction Set”.
Registers:0x28–0x2B
DMA Next Address (DNAD)
Read/Write
This 32-bit register contains the general purpose address pointer. At the
start of some SCRIPTS operations, its value is copied from the DMA
SCRIPTS Pointer Save (DSPS) register. Its value may not be valid except
in certain abort conditions. The default value of this register is zero.
Registers:0x2C–0x2F
DMA SCRIPTS Pointer (DSP)
Read/Write
To execute SCSI SCRIPTS, the address of the first SCRIPTS instruction
must be written to this register. In normal SCRIPTS operation, once the
starting address of the SCRIPTS is written to this register, SCRIPTS are
automatically fetched and executed until an interrupt condition occurs.
In the single step mode, there is a single step interrupt after each
instruction is executed. The DMA SCRIPTS Pointer (DSP) register does
not need to be written with the next address, but the Start DMA bit
(bit 2, DMA Control (DCNTL) register) must be set each time the step
interrupt occurs to fetch and execute the next SCRIPTS command. When
SCSI Registers
4-67
writing this register eight bits at a time, writing the upper eight bits begins
execution of SCSI SCRIPTS. The default value of this register is zero.
Registers:0x30–0x33
DMA SCRIPTS Pointer Save (DSPS)
Read/Write
This register contains the second dword of a SCRIPTS instruction. It is
overwritten each time a SCRIPTS instruction is fetched. When a
SCRIPTS interrupt instruction is executed, this register holds the
interrupt vector. The power-up value of this register is indeterminate.
Registers:0x34–0x37
Scratch Register A (SCRATCHA)
Read/Write
This is a general purpose, user-definable scratch pad register. Apart from
CPU access, only register read/write and memory moves into the
SCRATCH register alter its contents. The power-up value of this register
is indeterminate.
A special mode of this register is enabled by setting the PCI
Configuration Info Enable bit in the Chip Test Two (CTEST2) register. If
this bit is set, the Scratch Register A (SCRATCHA) register returns bits
[31:10] of the PCI Base Address Register One (MEMORY) in bits [31:10]
of the SCRATCH A register when read. Bits [9:0] of SCRATCH A will
always return zero in this mode. Writes to the SCRATCHA register are
unaffected. Clearing the PCI Configuration Info Enable bit causes the
SCRATCH A register to return to normal operation.
Register: 0x38
DMA Mode (DMODE)
Read/Write
7
0
6
0
5
SIOM
0
4
DIOM
0
3
ERL
0
2
ERMP
0
1
BOF
0
0
MAN
0
BL
BL
Burst Length
[7:6]
These bits control the maximum number of dwords
transferred per bus ownership, regardless of whether the
4-68
Registers
transfers are back to back, burst, or a combination of
both. This value is also independent of the width (64 or
32 bits) of the data transfer on the PCI bus. The
SYM53C896 SCSI function asserts the Bus Request
(REQ/) output when the DMA FIFO can accommodate a
transfer of at least one burst threshold of data. Bus
Request (REQ/) is also asserted during start-of-transfer
and end-of-transfer cleanup and alignment, even if less
than a full burst of transfers is performed. The
SYM53C896 SCSI function inserts a “fairness delay” of
four CLKs between burst transfers (as set in BL[2:0])
during normal operation. The fairness delay is not
inserted during PCI retry cycles. This gives the CPU and
other bus master devices the opportunity to access the
PCI bus between bursts.
The SYM53C896 will only support burst thresholds of up
to 16 dwords in the small FIFO mode. Setting the burst
threshold to higher than 16 dwords in the small FIFO
mode will yield unexpected results in burst lengths. The
big FIFO mode can be activated by setting bit 5 of the
Chip Test Five (CTEST5) register.
BL2
(CTEST5 bit 2)
Burst Length
Transfers
BL1
BL0
Dwords
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
2
4
8
4
8
16
16
321
32
641
64
1281
1281
Reserved
64
Reserved
1. The 944 Byte FIFO must be enabled for these burst sizes.
SIOM
Source I/O-Memory Enable
5
This bit is defined as an I/O Memory Enable bit for the
source address of a Memory Move or Block Move
Command. If this bit is set, then the source address is in
I/O space; and if cleared, then the source address is in
memory space.
SCSI Registers
4-69
This function is useful for register-to-memory operations
using the Memory Move instruction when a SYM53C896
SCSI function is I/O mapped. Bits 4 and 5 of the Chip Test
Two (CTEST2) register are used to determine the
configuration status of the SYM53C896 SCSI function.
DIOM
Destination I/O-Memory Enable
4
This bit is defined as an I/O Memory Enable bit for the
destination address of a Memory Move or Block Move
Command. If this bit is set, then the destination address
is in I/O space; and if cleared, then the destination
address is in memory space.
This function is useful for memory-to-register operations
using the Memory Move instruction when a SYM53C896
SCSI function is I/O mapped. Bits 4 and 5 of the Chip Test
Two (CTEST2) register are used to determine the
configuration status of the SYM53C896 SCSI function.
ERL
Enable Read Line
3
This bit enables a PCI Read Line command. If this bit is
set and the chip is about to execute a read cycle other
than an opcode fetch, then the command is 0b1110.
ERMP
BOF
Enable Read Multiple
2
If this bit is set and cache mode is enabled, a Read
Multiple command is used on all read cycles when it is
legal.
Burst Opcode Fetch Enable
1
Setting this bit causes the SYM53C896 SCSI function to
fetch instructions in burst mode. Specifically, the chip
bursts in the first two dwords of all instructions using a
single bus ownership. If the instruction is a Memory-to-
Memory Move type, the third dword is accessed in a
subsequent bus ownership. If the instruction is an indirect
type, the additional dword is accessed in a subsequent
bus ownership. If the instruction is a table indirect block
move type, the chip accesses the remaining two dwords
in a subsequent bus ownership, thereby fetching the four
dwords required in two bursts of two dwords each. If
prefetch is enabled, this bit has no effect. This bit also
has no effect on fetches out of SCRIPTS RAM.
4-70
Registers
MAN
Manual Start Mode
0
Setting this bit prevents the SYM53C896 SCSI function
from automatically fetching and executing SCSI
SCRIPTS when the DMA SCRIPTS Pointer (DSP) register
is written. When this bit is set, the Start DMA bit in the
DMA Control (DCNTL) register must be set to begin
SCRIPTS execution. Clearing this bit causes the
SYM53C896 SCSI function to automatically begin
fetching and executing SCSI SCRIPTS when the DMA
SCRIPTS Pointer (DSP) register is written. This bit
normally is not used for SCSI SCRIPTS operations.
Register: 0x39
DMA Interrupt Enable (DIEN)
Read/Write
7
R
x
6
MDPE
0
5
BF
0
4
ABRT
0
3
SSI
0
2
SIR
0
1
R
x
0
IID
0
R
Reserved
7
6
5
4
3
2
1
0
MDPE
BF
Master Data Parity Error
Bus Fault
ABRT
SSI
SIR
R
Aborted
Single Step Interrupt
SCRIPTS Interrupt Instruction Received
Reserved
IID
Illegal Instruction Detected
This register contains the interrupt mask bits corresponding to the
interrupting conditions described in the DMA Status (DSTAT) register. An
interrupt is masked by clearing the appropriate mask bit. Masking an
interrupt prevents INTA/ (for Function A) or INTB/ (for Function B) from
being asserted for the corresponding interrupt, but the status bit is still
set in the DMA Status (DSTAT) register. Masking an interrupt does not
prevent setting the Interrupt Status Zero (ISTAT0) DIP. All DMA interrupts
are considered fatal, therefore SCRIPTS stops running when this
SCSI Registers
4-71
condition occurs, whether or not the interrupt is masked. Setting a mask
bit enables the assertion of INTA/, or INTB/, for the corresponding
interrupt. (A masked nonfatal interrupt does not prevent unmasked or
fatal interrupts from getting through; interrupt stacking begins when either
the Interrupt Status Zero (ISTAT0) SIP or DIP bit is set.)
The INTA/ and INTB/ outputs are latched. Once asserted, they remain
asserted until the interrupt is cleared by reading the appropriate status
register. Masking an interrupt after the INTA/, or INTB/, output is asserted
does not cause deassertion of INTA/, or INTB/.
For more information on interrupts, see Chapter 2, “Functional
Description”.
Register: 0x3A
Scratch Byte Register (SBR)
Read/Write
This is a general purpose register. Apart from CPU access, only register
read/write and memory moves into this register alter its contents. The
default value of this register is zero. This register is called the DMA
Watchdog Timer on previous SYM53C8XX family products.
Register: 0x3B
DMA Control (DCNTL)
Read/Write
7
CLSE
0
6
PFF
0
5
PFEN
0
4
SSM
0
3
IRQM
0
2
STD
0
1
IRQD
0
0
COM
0
CLSE
Cache Line Size Enable
7
Setting this bit enables the SYM53C896 SCSI function to
sense and react to cache line boundaries set up by the
DMA Mode (DMODE) or PCI Cache Line Size register,
whichever contains the smaller value. Clearing this bit
disables the cache line size logic and the SYM53C896
SCSI function monitors the cache line size using the
DMODE register.
4-72
Registers
PFF
Prefetch Flush
Setting this bit causes the prefetch unit to flush its
contents. This bit clears after the flush is complete.
6
5
PFEN
Prefetch Enable
Setting this bit enables an 8-dword SCRIPTS instruction
prefetch unit. The prefetch unit, when enabled, will fetch
8 dwords of instructions and instruction operands in
bursts of 4 or 8 dwords. Prefetching instructions allows
the SYM53C896 SCSI function to make more efficient
use of the system PCI bus, thus improving overall system
performance. The unit will flush whenever the PFF bit is
set, as well as on all transfer control instructions when
the transfer conditions are met, on every write to the DMA
SCRIPTS Pointer (DSP), on every regular MMOV
instruction, and when any interrupt is generated. The unit
automatically determines the maximum burst size that it
is capable of performing based on the burst length as
determined by the values in the DMA Mode (DMODE)
register. If the burst threshold is set to 8 dwords the
prefetch unit will fetch instructions in two bursts of 4
dwords. If the burst threshold is set to 16 dwords or
greater the prefetch unit will fetch instructions in one burst
of 8 dwords. Burst thresholds of less than 8 dwords will
cause the prefetch unit to be disabled. PCI Cache
commands (Read Line and Read Multiple) will be issued
appropriately if PCI caching is enabled. Prefetching from
SCRIPTS RAM is not supported and is unnecessary due
to the speed of the fetches. When fetching from
SCRIPTS RAM the setting of this bit will have no effect
on the fetch mechanism from SCRIPTS RAM. The
prefetch unit does not support 64-bit data instruction
fetches across the PCI bus. Prefetches of SCRIPTS
instructions will always be 32 bits in width.
SSM
Single Step Mode
4
Setting this bit causes the SYM53C896 SCSI function to
stop after executing each SCRIPTS instruction, and
generate a single step interrupt. When this bit is cleared
the SYM53C896 SCSI function does not stop after each
instruction. It continues fetching and executing
instructions until an interrupt condition occurs. For normal
SCSI SCRIPTS operation, keep this bit cleared. To
restart the SYM53C896 SCSI function after it generates
SCSI Registers
4-73
a SCRIPTS Step interrupt, read the Interrupt Status Zero
(ISTAT0) and DMA Status (DSTAT) registers to recognize
and clear the interrupt. Then set the START DMA bit in
this register.
IRQM
STD
IRQ Mode
3
When set, this bit enables a totem pole driver for the
INTA/, or INTB/ pin. When cleared, this bit enables an
open drain driver for the INTA/, or INTB/, pin with an
internal weak pull-up. The bit should remain cleared to
retain full PCI compliance.
Start DMA Operation
2
The SYM53C896 SCSI function fetches a SCSI
SCRIPTS instruction from the address contained in the
DMA SCRIPTS Pointer (DSP) register when this bit is set.
This bit is required if the SYM53C896 SCSI function is in
one of the following modes:
•
Manual start mode – Bit 0 in the DMA Mode (DMODE)
register is set
•
Single step mode – Bit 4 in the DMA Control (DCNTL)
register is set
When the SYM53C896 SCSI function is executing
SCRIPTS in manual start mode, the Start DMA bit must
be set to start instruction fetches, but need not be set
again until an interrupt occurs. When the SYM53C896
SCSI function is in single step mode, set the Start DMA
bit to restart execution of SCRIPTS after a single step
interrupt.
IRQD
INTA, INTB Disable
1
Setting this bit disables the INTA (for SCSI Function A),
or INTB (for SCSI Function B) pin. Clearing the bit
enables normal operation. As with any other register
other than Interrupt Status Zero (ISTAT0), Interrupt Status
One (ISTAT1), Mailbox Zero (MBOX0), Mailbox One
(MBOX1), this register cannot be accessed except by a
SCRIPTS instruction during SCRIPTS execution. For
more information on the use of this bit in interrupt
handling, see Chapter 2, “Functional Description”.
COM
SYM53C700 Compatibility
0
When the COM bit is cleared, the SYM53C896 SCSI
function behaves in a manner compatible with the
4-74
Registers
SYM53C700; selection/reselection IDs are stored in both
the SCSI Selector ID (SSID) and SCSI First Byte Received
(SFBR) registers. This bit is not affected by a software
reset.
If the COM bit is cleared, do not access this register
using SCRIPTS operation as nondeterminate operations
may occur. (This includes SCRIPTS Read/Write
operations and conditional transfer control instructions
that initialize the SCSI First Byte Received (SFBR)
register.)
When the COM bit is set, the ID is stored only in the SCSI
Selector ID (SSID) register, protecting the SCSI First Byte
Received (SFBR) from being overwritten if a
selection/reselection occurs during a DMA register-to-
register operation.
Registers:0x3C–0x3F
Adder Sum Output (ADDER)
Read Only
This register contains the output of the internal adder, and is used
primarily for test purposes. The power-up value for this register is
indeterminate.
Register: 0x40
SCSI Interrupt Enable Zero (SIEN0)
Read/Write
7
M/A
0
6
CMP
0
5
SEL
0
4
RSL
0
3
SGE
0
2
UDC
0
1
RST
0
0
PAR
0
This register contains the interrupt mask bits corresponding to the
interrupting conditions described in the SCSI Interrupt Status Zero (SIST0)
register. An interrupt is masked by clearing the appropriate mask bit. For
more information on interrupts see Chapter 2, “Functional Description”.
M/A
SCSI Phase Mismatch - Initiator Mode; SCSI
ATN Condition - Target Mode
7
In the initiator mode, this bit is set when the SCSI phase
asserted by the target and sampled during SREQ/ does
not match the expected phase in the SCSI Output Control
SCSI Registers
4-75
Latch (SOCL) register. This expected phase is
automatically written by SCSI SCRIPTS. In the target
mode, this bit is set when the initiator asserts SATN/. See
the Disable Halt on Parity Error or SATN/ Condition bit in
the SCSI Control One (SCNTL1) register for more
information on when this status is actually raised.
CMP
SEL
Function Complete
Indicates full arbitration and selection sequence is
completed.
6
Selected
5
Indicates the SYM53C896 SCSI function is selected by a
SCSI initiator device. Set the Enable Response to
Selection bit in the SCSI Chip ID (SCID) register for this
to occur.
RSL
SGE
Reselected
4
Indicates the SYM53C896 SCSI function is reselected by
a SCSI target device. Set the Enable Response to
Reselection bit in the SCSI Chip ID (SCID) register for this
to occur.
SCSI Gross Error
3
The following conditions are considered SCSI Gross
Errors:
•
Data underflow - reading the SCSI FIFO when no
data is present.
•
•
Data overflow - writing to the SCSI FIFO while it is full.
Offset underflow - receiving a SACK/ pulse in the
target mode before the corresponding SREQ/ is sent.
•
Offset overflow - receiving a SREQ/ pulse in the
initiator mode, and exceeding the maximum offset
(defined by the MO[3:0] bits in the SCSI Transfer
(SXFER) register).
•
•
A phase change in the initiator mode, with an
outstanding SREQ/SACK offset.
Residual data in SCSI FIFO - starting a transfer other
than synchronous data receive with data left in the
SCSI synchronous receive FIFO.
4-76
Registers
UDC
Unexpected Disconnect
2
This condition only occurs in the initiator mode. It
happens when the target to which the SYM53C896 SCSI
function is connected disconnects from the SCSI bus
unexpectedly. See the SCSI Disconnect Unexpected bit
in the SCSI Control Two (SCNTL2) register for more
information on expected versus unexpected disconnects.
Any disconnect in the low level mode causes this
condition.
RST
PAR
SCSI Reset Condition
1
Indicates assertion of the SRST/ signal by the
SYM53C896 SCSI function or any other SCSI device.
This condition is edge-triggered, so multiple interrupts
cannot occur because of a single SRST/ pulse.
SCSI Parity Error
0
Indicates detection by the SYM53C896 SCSI function of
a parity error while receiving or sending SCSI data. See
the Disable Halt on Parity Error or SATN/ Condition bits
in the SCSI Control One (SCNTL1) register for more infor-
mation on when this condition is actually raised.
Register: 0x41
SCSI Interrupt Enable One (SIEN1)
Read/Write
7
x
5
x
4
SBMC
x
3
R
x
2
STO
0
1
GEN
0
0
HTH
0
R
x
This register contains the interrupt mask bits corresponding to the
interrupting conditions described in the SCSI Interrupt Status One (SIST1)
register. An interrupt is masked by clearing the appropriate mask bit. For
more information on interrupts refer to Chapter 2, “Functional Description”.
R
Reserved
[7:5]
4
SBMC
SCSI Bus Mode Change
Setting this bit allows the SYM53C896 to generate an
interrupt when the DIFFSENS pin detects a change in
voltage level that indicates the SCSI bus has changed
between SE, LVD, or HVD modes. For example, when
this bit is cleared and the SCSI bus changes modes, IRQ/
SCSI Registers
4-77
does not assert and the SIP bit in the Interrupt Status Zero
(ISTAT0) register is not set. However, bit 4 in the SCSI
Interrupt Status One (SIST1) register is set. Setting this bit
allows the interrupt to occur.
R
Reserved
3
STO
Selection or Reselection Time-out
2
The SCSI device which the SYM53C896 SCSI function is
attempting to select or reselect does not respond within
the programmed time-out period. See the description of
the SCSI Timer Zero (STIME0) register bits [3:0] for more
information on the time-out timer.
GEN
HTH
General Purpose Timer Expired
1
The general purpose timer is expired. The time measured
is the time between enabling and disabling of the timer.
See the description of the SCSI Timer One (STIME1)
register, bits [3:0], for more information on the general
purpose timer.
Handshake-to-Handshake Timer Expired
The handshake-to-handshake timer is expired. The time
measured is the SCSI Request-to-Request (target) or
Acknowledge-to-Acknowledge (initiator) period. See the
description of the SCSI Timer Zero (STIME0) register, bits
[7:4], for more information on the
0
handshake-to-handshake timer.
4-78
Registers
Register: 0x42
SCSI Interrupt Status Zero (SIST0)
Read Only
7
M/A
0
6
CMP
0
5
SEL
0
4
RSL
0
3
SGE
0
2
UDC
0
1
RST
0
0
PAR
0
Reading the SCSI Interrupt Status Zero (SIST0) register returns the status
of the various interrupt conditions, whether they are enabled in the SCSI
Interrupt Enable Zero (SIEN0) register or not. Each bit set indicates
occurrence of the corresponding condition. Reading the SIST0 clears the
interrupt status.
Reading this register clears any bits that are set at the time the register
is read, but does not necessarily clear the register because additional
interrupts may be pending (the SYM53C896 SCSI functions stack
interrupts). SCSI interrupt conditions are individually masked through the
SCSI Interrupt Enable Zero (SIEN0) register.
When performing consecutive 8-bit reads of the DMA Status (DSTAT),
SCSI Interrupt Status Zero (SIST0), and SCSI Interrupt Status One (SIST1)
registers (in any order), insert a delay equivalent to 12 clock periods
between the reads to ensure the interrupts clear properly. Also, if reading
the registers when both the Interrupt Status Zero (ISTAT0) SIP and DIP
bits may not be set, read the SIST0 and SIST1 registers before the
DSTAT register to avoid missing a SCSI interrupt. For more information
on interrupts refer to Chapter 2, “Functional Description”.
M/A
Initiator Mode: Phase Mismatch; Target Mode:
SATN/ Active
7
In the initiator mode, this bit is set if the SCSI phase
asserted by the target does not match the instruction.
The phase is sampled when SREQ/ is asserted by the
target. In the target mode, this bit is set when the SATN/
signal is asserted by the initiator.
CMP
SEL
Function Complete
This bit is set when an arbitration only or full arbitration
sequence is completed.
6
Selected
5
This bit is set when the SYM53C896 SCSI function is
selected by another SCSI device. The Enable Response
SCSI Registers
4-79
to Selection bit must be set in the SCSI Chip ID (SCID)
register (and the Response ID Zero (RESPID0) and
Response ID One (RESPID1) registers must hold the
chip’s ID) for the SYM53C896 SCSI function to respond
to selection attempts.
RSL
Reselected
4
This bit is set when the SYM53C896 SCSI function is
reselected by another SCSI device. The Enable
Response to Reselection bit must be set in the SCSI Chip
ID (SCID) register (and the Response ID Zero (RESPID0)
and Response ID One (RESPID1) registers must hold the
chip’s ID) for the SYM53C896 SCSI function to respond
to reselection attempts.
SGE
SCSI Gross Error
3
This bit is set when the SYM53C896 SCSI function
encounters a SCSI Gross Error Condition. The following
conditions can result in a SCSI Gross Error Condition:
•
Data Underflow - reading the SCSI FIFO when no
data is present.
•
Data Overflow - writing too many bytes to the SCSI
FIFO, or the synchronous offset causes overwriting
the SCSI FIFO.
•
•
Offset Underflow - the SYM53C896 SCSI function is
operating in the target mode and a SACK/ pulse is
received when the outstanding offset is zero.
Offset Overflow - the other SCSI device sends a
SREQ/ or SACK/ pulse with data which exceeds the
maximum synchronous offset defined by the SCSI
Transfer (SXFER) register.
•
•
A phase change occurs with an outstanding
synchronous offset when the SYM53C896 SCSI
function is operating as an initiator.
Residual data in the synchronous data FIFO - a
transfer other than synchronous data receive is
started with data left in the synchronous data FIFO.
UDC
Unexpected Disconnect
2
This bit is set when the SYM53C896 SCSI function is
operating in the initiator mode and the target device
unexpectedly disconnects from the SCSI bus. This bit is
4-80
Registers
only valid when the SYM53C896 SCSI function operates
in the initiator mode. When the SCSI function operates in
the low level mode, any disconnect causes an interrupt,
even a valid SCSI disconnect. This bit is also set if a
selection time-out occurs (it may occur before, at the
same time, or stacked after the STO interrupt, since this
is not considered an expected disconnect).
RST
SCSI RST/ Received
1
This bit is set when the SYM53C896 SCSI function
detects an active SRST/ signal, whether the reset is
generated external to the chip or caused by the Assert
SRST/ bit in the SCSI Control One (SCNTL1) register.
This SCSI reset detection logic is edge-sensitive, so that
multiple interrupts are not generated for a single
assertion of the SRST/ signal.
PAR
Parity Error
0
This bit is set when the SYM53C896 SCSI function
detects a parity error while receiving SCSI data. The
Enable Parity Checking bit (bit 3 in the SCSI Control Zero
(SCNTL0) register) must be set for this bit to become
active. The SYM53C896 SCSI function always generates
parity when sending SCSI data.
Register: 0x43
SCSI Interrupt Status One (SIST1)
Read Only
7
0
5
0
4
SBMC
0
3
R
0
2
STO
0
1
GEN
0
0
HTH
0
R
0
Reading the SIST1 register returns the status of the various interrupt
conditions, whether they are enabled in the SCSI Interrupt Enable One
(SIEN1) register or not. Each bit that is set indicates an occurrence of
the corresponding condition.
Reading the SIST1 clears the interrupt condition.
SCSI Registers
4-81
R
Reserved
[7:5]
4
SBMC
SCSI Bit Mode Change
This bit is set when the DIFFSENS pin detects a change
in voltage level that indicates the SCSI bus has switched
between SE, LVD or HVD modes.
R
Reserved
3
STO
Selection or Reselection Time-Out
2
The SCSI device which the SYM53C896 SCSI function is
attempting to select or reselect does not respond within
the programmed time-out period. See the description of
the SCSI Timer Zero (STIME0) register, bits [3:0], for more
information on the time-out timer.
GEN
HTH
General Purpose Timer Expired
1
This bit is set when the general purpose timer expires.
The time measured is the time between enabling and
disabling of the timer. See the description of the SCSI
Timer One (STIME1) register, bits [3:0], for more
information on the general purpose timer.
Handshake-to-Handshake Timer Expired
0
This bit is set when the handshake-to-handshake timer
expires. The time measured is the SCSI Request to
Request (target) or Acknowledge-to-Acknowledge
(initiator) period. See the description of the SCSI Timer
Zero (STIME0) register, bits [7:4], for more information on
the handshake-to-handshake timer.
Register: 0x44
SCSI Longitudinal Parity (SLPAR)
Read/Write
This register performs a bytewise longitudinal parity check on all SCSI
data received or sent through the SCSI core. If one of the bytes received
or sent (usually the last) is the set of correct even parity bits, SLPAR
should go to zero (assuming it started at zero). As an example, suppose
that the following three data bytes and one check byte are received from
the SCSI bus (all signals are shown active high):
4-82
Registers
Data Bytes
Running SLPAR
–
00000000
1. 11001100 11001100 (XOR of word 1)
2. 01010101 10011001 (XOR of word 1 and 2)
3. 00001111 10010110 (XOR of word 1, 2 and 3)
4. 10010110 00000000
A one in any bit position of the final SLPAR value would indicate a
transmission error.
The SLPAR register is also used to generate the check bytes for SCSI
send operations. If the SCSI Longitudinal Parity (SLPAR) register contains
all zeros prior to sending a block move, it contains the appropriate check
byte at the end of the block move. This byte must then be sent across
the SCSI bus.
Note:
Writing any value to this register clears it to zero.
The longitudinal parity checks are meant to provide an added measure
of SCSI data integrity and are entirely optional. This register does not
latch SCSI selection/reselection IDs under any circumstances. The
default value of this register is zero.
The longitudinal parity function normally operates as a byte function.
During 16-bit transfers, the high and low bytes are XORed together and
then XORed into the current longitudinal parity value. By setting the
SLPMD bit in the SCSI Control Two (SCNTL2) register, the longitudinal
parity function is made to operate as a word-wide function. During 16-bit
transfers, the high byte of the SCSI bus is XORed with the high byte of
the current longitudinal parity value, and the low byte of the SCSI bus is
XORed with the low byte of the current longitudinal parity value. In this
mode, the 16-bit longitudinal parity value is accessed a byte at a time
through the SCSI Longitudinal Parity (SLPAR) register. Which byte is
accessed is controlled by the SLPHBEN bit in the SCSI Control Two
(SCNTL2) register.
SCSI Registers
4-83
Register: 0x45
SCSI Wide Residue (SWIDE)
Read/Write
After a wide SCSI data receive operation, this register contains a residual
data byte if the last byte received was never sent across the DMA bus.
It represents either the first data byte of a subsequent data transfer, or it
is a residue byte which should be cleared when an Ignore Wide Residue
message is received. It may also be an overrun data byte. The power-up
value of this register is indeterminate.
Register: 0x46
Chip Type (CTYPE)
Read Only
7
1
4
1
3
x
0
x
TYP
R
1
1
x
x
TYP
Chip Type
[7:4]
These bits identify the chip type for software purposes.
Note:
These bits no longer identify an 8XX device. These bits
have been set to 0xF to indicate that the device should be
uniquely identified by setting the PCI Configuration Enable
bit in the Chip Test Two (CTEST2) register and using the
PCI Revision ID (Rev ID) and PCI Device ID which will be
shadowed in the SCRIPTS Fetch Selector (SFS) register.
Any devices that contain the value 0xF in this register
should use this mechanism to uniquely identify the device.
R
Reserved
[3:0]
4-84
Registers
Register: 0x47
General Purpose Pin Control (GPCNTL)
Read/Write
7
ME
0
6
FE
0
5
LEDC
0
4
0
2
1
1
1
0
1
GPIO
1
GPIO
This register is used to determine if the pins controlled by the General
Purpose (GPREG) are inputs or outputs. Bits [4:0] in GPCNTL
correspond to bits [4:0] in the GPREG register. When the bits are
enabled as inputs, an internal pull-down is also enabled. If either SCSI
function GPCNTL register has a GPIO pin set as an output, the pin is
enabled as an output. If both the SCSI function GPREG registers define
a single GPIO pin as an output, the results are indeterminate.
ME
Master Enable
7
The internal bus master signal is presented on GPIO1 if
this bit is set, regardless of the state of bit 1 (GPIO1).
FE
Fetch Enable
6
The internal opcode fetch signal is presented on GPIO0
if this bit is set, regardless of the state of bit 0 (GPIO0).
LEDC
LED_CNTL
5
The internal connected signal (bit 3 of the Interrupt Status
Zero (ISTAT0) register) will be presented on GPIO0 if this
bit is set and bit 6 of GPCNTL is cleared and the chip is
not in progress of performing an EEPROM autodownload
regardless of the state of bit 0 (GPIO0). This provides a
hardware solution to driving a SCSI activity LED in many
implementations of LSI Logic SCSI chips.
GPIO
GPIO
GPIO Enable
[4:2]
General purpose control, corresponding to bit 4 in the
General Purpose (GPREG) register and the GPIO4 pin.
GPIO4 powers up as a general purpose output, and
GPIO[3:2] power-up as general purpose inputs.
GPIO Enable
[1:0]
These bits power-up set, causing the GPIO1 and GPIO0
pins to become inputs. Clearing these bits causes
GPIO[1:0] to become outputs.
SCSI Registers
4-85
Register: 0x48
SCSI Timer Zero (STIME0)
Read/Write
7
4
0
3
0
0
0
HTH[3:0]
SEL[3:0]
0
0
0
0
0
HTH[3:0]
Handshake-to-Handshake Timer Period
[7:4]
These bits select the handshake-to-handshake time-out
period, the maximum time between SCSI handshakes
(SREQ/ to SREQ/ in target mode, or SACK/ to SACK/ in
the initiator mode). When this timing is exceeded, an
interrupt is generated and the HTH bit in the SCSI
Interrupt Status One (SIST1) register is set. The following
table contains time-out periods for the Handshake-to-
Handshake Timer, the Selection/Reselection Timer (bits
[3:0]), and the General Purpose Timer (SCSI Timer One
(STIME1) bits [3:0]). For a more detailed explanation of
interrupts, refer to Chapter 2, “Functional Description”.
4-86
Registers
HTH[7:4], SEL[3:0], GEN[3:0]1
Minimum Time-Out
(40 or 160 MHz)2
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Disabled
125 µs
250 µs
500 µs
1 ms
2 ms
4 ms
8 ms
16 ms
32 ms
64 ms
128 ms
256 ms
512 ms
1.024 sec
2.048 sec
1. These values will be correct if the CCF bits in the SCSI
Control Three (SCNTL3) register are set according to the
valid combinations in the bit description.
2. A quadrupled 40 MHz clock is required for Ultra2 SCSI
operation.
SEL[3:0]
Selection Time-Out
[3:0]
These bits select the SCSI selection/reselection time-out
period. When this timing (plus the 200 µs selection abort
time) is exceeded, the STO bit in the SCSI Interrupt Status
One (SIST1) register is set. For a more detailed
explanation of interrupts, refer to Chapter 2, “Functional
Description”.
SCSI Registers
4-87
Register: 0x49
SCSI Timer One (STIME1)
Read/Write
7
R
x
6
HTHBA
0
5
GENSF
0
4
HTHSF
0
3
0
0
0
GEN[3:0]
0
0
R
Reserved
7
6
HTHBA
Handshake-to-Handshake Timer Bus Activity
Enable
Setting this bit causes this timer to begin testing for SCSI
REQ/ and ACK/ activity as soon as SBSY/ is asserted,
regardless of the agents participating in the transfer.
GENSF
General Purpose Timer Scale Factor
Setting this bit causes this timer to shift by a factor of 16.
Refer to the SCSI Timer Zero (STIME0) register
description for details.
5
4-88
Registers
Minimum Time-Out
(50 MHz Clock)2
HTH[7:4], SEL[3:0],
GEN[3:0]1
HTHSF = 0,
GENSF = 0
HTHSF = 1,
GENSF = 1
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Disabled
100 µs
Disabled
1.6 ms
3.2 ms
6.4 ms
12.8 ms
25.6 ms
51.2 ms
102.4 ms
204.8 ms
409.6 ms
819.2 ms
1.6 s
200 µs
400 µs
800 µs
1.6 ms
3.2 ms
6.4 ms
12.8 ms
25.6 ms
51.2 ms
102.4 ms
204.8 ms
409.6 ms
819.2 ms
1.6 s
3.2 s
6.4 s
12.8 s
25.6 s
1. These values will be correct if the CCF bits in the SCSI
Control Three (SCNTL3) register are set according to the
valid combinations in the bit description.
2. 50 MHz clock is not supported for Ultra2 SCSI operation.
HTHSF
Handshake-to-Handshake Timer Scale Factor
4
Setting this bit causes this timer to shift by a factor of 16.
Refer to the SCSI Timer Zero (STIME0) register
description for details.
GEN[3:0]
General Purpose Timer Period
[3:0]
These bits select the period of the general purpose timer.
The time measured is the time between enabling and
disabling of the timer. When this timing is exceeded, the
GEN bit in the SCSI Interrupt Status One (SIST1) register
is set. Refer to the table under SCSI Timer Zero (STIME0),
bits [3:0], for the available time-out periods.
SCSI Registers
4-89
Minimum Time-out
(40 or 160 MHz Clock)2
HTH[7:4], SEL[3:0],
GEN[3:0]1
HTHSF = 0,
GENSF = 0
HTHSF = 1,
GENSF = 1
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Disabled
125 µs
250 µs
500 µs
1 µs
Disabled
2 ms
4 ms
8 ms
16 ms
32 ms
64 ms
128 ms
256 ms
512 ms
1 s
2 ms
4 ms
8 ms
16 ms
32 ms
64 ms
128 ms
256 ms
512 ms
1.024 s
2.048 s
2 s
4.1 s
8.2 s
16.4 s
32.8 s
1. These values will be correct if the CCF bits in the SCSI
Control Three (SCNTL3) register are set according to the valid
combinations in the bit description.
2. Ultra2 SCSI operation requires a quadrupled 40 MHz clock.
Note:
To reset a timer before it expires and obtain repeatable
delays, the time value must be written to zero first, and then
written back to the desired value. This is also required
when changing from one time value to another.
4-90
Registers
Register: 0x4A
Response ID Zero (RESPID0)
Read/Write
7
0
x
ID
x
x
x
x
x
x
x
RESPID0 and Response ID One (RESPID1) contain the selection or
reselection IDs. In other words, these two 8-bit registers contain the ID
that the chip responds to on the SCSI bus. Each bit represents one
possible ID with the most significant bit of Response ID One (RESPID1)
representing ID 15 and the least significant bit of RESPID0 representing
ID 0. The SCSI Chip ID (SCID) register still contains the chip ID used
during arbitration. The chip can respond to more than one ID because
more than one bit can be set in the RESPID1 and RESPID0 registers.
However, the chip can arbitrate with only one ID value in the SCSI Chip
ID (SCID) register.
Register: 0x4B
Response ID One (RESPID1)
Read/Write
15
x
8
x
ID
x
x
x
x
x
x
Response ID Zero (RESPID0) and RESPID1 contain the selection or
reselection IDs. In other words, these two 8-bit registers contain the ID
that the chip responds to on the SCSI bus. Each bit represents one
possible ID with the most significant bit of RESPID1 representing ID 15
and the least significant bit of RESPID0 representing ID 0. The SCSI
Chip ID (SCID) register still contains the chip ID used during arbitration.
The chip can respond to more than one ID because more than one bit
can be set in the RESPID1 and RESPID0 registers. However, the chip
can arbitrate with only one ID value in the SCSI Chip ID (SCID) register.
SCSI Registers
4-91
Register: 0x4C
SCSI Test Zero (STEST0)
Read Only
7
4
x
3
SLT
0
2
ART
0
1
SOZ
1
0
SOM
1
SSAID
x
x
x
SSAID
SCSI Selected As ID
[7:4]
These bits contain the encoded value of the SCSI ID that
the SYM53C896 SCSI function is selected or reselected
as during a SCSI selection or reselection phase. These
bits are read only and contain the encoded value of 0–15
possible IDs that could be used to select the SYM53C896
SCSI function. During a SCSI selection or reselection
phase when a valid ID is put on the bus, and the
SYM53C896 SCSI function responds to that ID, the
“selected as” ID is written into these bits. These bits are
used with Response ID Zero (RESPID0) and Response ID
One (RESPID1) registers to allow response to multiple
IDs on the bus.
SLT
Selection Response Logic Test
3
This bit is set when the SYM53C896 SCSI function is
ready to be selected or reselected. This does not take
into account the bus settle delay of 400 ns. This bit is
used for functional test and fault purposes.
ART
Arbitration Priority Encoder Test
2
This bit is always set when the SYM53C896 SCSI
function exhibits the highest priority ID asserted on the
SCSI bus during arbitration. It is primarily used for chip
level testing, but it may be used during low level mode
operation to determine if the SYM53C896 SCSI function
won arbitration.
SOZ
SCSI Synchronous Offset Zero
1
This bit indicates that the current synchronous SREQ/,
SACK/ offset is zero. This bit is not latched and may
change at any time. It is used in low level synchronous
SCSI operations. When this bit is set, the SYM53C896
SCSI functioning as an initiator, is waiting for the target
to request data transfers. If the SYM53C896 SCSI is
4-92
Registers
functioning as a target, then the initiator has sent the
offset number of acknowledges.
SOM
SCSI Synchronous Offset Maximum
0
This bit indicates that the current synchronous SREQ/,
SACK/ offset is the maximum specified by bits [3:0] in the
SCSI Transfer (SXFER) register. This bit is not latched and
may change at any time. It is used in low level
synchronous SCSI operations. When this bit is set, the
SYM53C896 SCSI is functioning as a target, and is
waiting for the initiator to acknowledge the data transfers.
If the SYM53C896 SCSI is functioning as an initiator,
then the target has sent the offset number of requests.
Register: 0x4D
SCSI Test One (STEST1)
Read/Write
7
SCLK
0
6
ISO
0
5
x
4
x
3
QEN
0
2
QSEL
0
1
0
0
0
R
IRM[1:0]
SCLK
SCSI Clock
7
When set, this bit disables the external SCLK (SCSI
Clock) pin, and the chip uses the PCI clock as the
internal SCSI clock. If a transfer rate of 10 Mbytes/s (or
20 Mbytes/s on a wide SCSI bus) is desired on the SCSI
bus, this bit must be cleared and at least a 40 MHz
external SCLK must be provided.
ISO
SCSI Isolation Mode
6
This bit allows the SYM53C896 SCSI function to put the
SCSI bidirectional and input pins into a low power mode
when the SCSI bus is not in use. When this bit is set, the
SCSI bus inputs are logically isolated from the SCSI bus.
R
Reserved
[5:4]
3
QEN
SCLK Quadrupler Enable
This bit, when set, powers up the internal clock
quadrupler circuit, which quadruples the SCLK 40 MHz
clock to an internal 160 MHz SCSI clock required for
Fast-20 and Fast-40 SCSI operation. When cleared, this
bit powers down the internal quadrupler circuit.
SCSI Registers
4-93
QSEL
SCLK Quadrupler Select
2
This bit, when set, selects the output of the internal clock
doubler for use as the internal SCSI clock. When cleared,
this bit selects the clock presented on SCLK for use as
the internal SCSI clock.
IRM[1:0]
Interrupt Routing Mode
[1:0]
The SYM53C896 supports four different interrupt routing
modes. These modes are described in the following table.
Each SCSI core within the chip can be configured
independently. Mode 0 is the default mode and is
compatible with AMI RAID upgrade products.
Mode
Bits [1:0]
Operation
0
00
If the INT_DIR/ input pin is low,
interrupts are signaled on ALT_INTx/.
Otherwise, interrupts are signaled on
both INTx/ and ALT_INTx/.
1
2
3
01
10
11
Interrupts are only signaled on INTx/,
not ALT_INTx/, and the INT_DIR/
input pin is ignored.
Interrupts are only signaled on
ALT_INTx/, and the INT_DIR/ input pin
is ignored.
Interrupts are signaled on both INTx/
and ALT_INTx/, and the INT_DIR
input pin is ignored.
Register: 0x4E
SCSI Test Two (STEST2)
Read/Write
7
SCE
0
6
ROF
0
5
DIF
0
4
SLB
0
3
SZM
0
2
AWS
0
1
EXT
0
0
LOW
0
SCE
SCSI Control Enable
Setting this bit allows assertion of all SCSI control and
7
data lines through the SCSI Output Control Latch (SOCL)
and SCSI Output Data Latch (SODL) registers regardless
of whether the SYM53C896 SCSI function is configured
as a target or initiator.
4-94
Registers
Note:
Do not set this bit during normal operation, since it could
cause contention on the SCSI bus. It is included for
diagnostic purposes only.
ROF
DIF
Reset SCSI Offset
Setting this bit clears any outstanding synchronous
SREQ/SACK offset. If a SCSI gross error occurs, set this
bit. This bit automatically clears itself after resetting the
synchronous offset.
6
HVD or SE/LVD
5
Setting this bit allows the SYM53C896 SCSI function to
interface to external HVD transceivers. Clearing this bit
enables SE or LVD operation. Set this bit in the
initialization routine if the HVD pair interface is used.
SLB
SZM
SCSI Loopback Mode
4
Setting this bit allows the SYM53C896 SCSI function to
perform SCSI loopback diagnostics. That is, it enables
the SCSI core to simultaneously perform as both the
initiator and the target.
SCSI High Impedance Mode
3
Setting this bit places all the open drain 48 mA SCSI
drivers into a high impedance state. This is to allow
internal loopback mode operation without affecting the
SCSI bus.
AWS
EXT
Always Wide SCSI
2
When this bit is set, all SCSI information transfers are
done in the 16-bit wide mode. This includes data,
message, command, status and reserved phases.
Normally, deassert this bit since 16-bit wide message,
command, and status phases are not supported by the
SCSI specifications.
Extend SREQ/SACK/ Filtering
1
LSI Logic TolerANT SCSI receiver technology includes a
special digital filter on the SREQ/ and SACK/ pins which
causes the disregarding of glitches on deasserting
edges. Setting this bit increases the filtering period from
30 ns to 60 ns on the deasserting edge of the SREQ/ and
SACK/ signals.
SCSI Registers
4-95
Note:
Never set this bit during fast SCSI (greater than 5 Mbytes
transfers per second) operations, because a valid assertion
could be treated as a glitch.
LOW
SCSI Low level Mode
0
Setting this bit places the SYM53C896 SCSI function in
low level mode. In this mode, no DMA operations occur,
and no SCRIPTS execute. Arbitration and selection may
be performed by setting the start sequence bit as
described in the SCSI Control Zero (SCNTL0) register.
SCSI bus transfers are performed by manually asserting
and polling SCSI signals. Clearing this bit allows
instructions to be executed in the SCSI SCRIPTS mode.
Note:
It is not necessary to set this bit for access to the SCSI
bit-level registers (SCSI Output Data Latch (SODL), SCSI
Bus Control Lines (SBCL), and input registers).
Register: 0x4F
SCSI Test Three (STEST3)
Read/Write
7
TE
0
6
STR
0
5
HSC
0
4
DSI
0
3
S16
0
2
TTM
0
1
CSF
0
0
STW
0
TE
TolerANT Enable
7
Setting this bit enables the active negation portion of
LSI Logic TolerANT technology. Active negation causes
the SCSI Request, Acknowledge, Data, and Parity
signals to be actively deasserted, instead of relying on
external pull-ups, when the SYM53C896 SCSI function is
driving these signals. Active deassertion of these signals
occurs only when the SYM53C896 SCSI function is in an
information transfer phase. When operating in a
differential environment or at fast SCSI timings, TolerANT
Active negation should be enabled to improve setup and
deassertion times. Active negation is disabled after reset
or when this bit is cleared. For more information on
LSI Logic TolerANT technology, see Chapter 1,
“Introduction”.
4-96
Registers
Note:
Set this bit if the Enable Ultra SCSI bit in SCSI Control
Three (SCNTL3) is set.
STR
SCSI FIFO Test Read
6
Setting this bit places the SCSI core into a test mode in
which the SCSI FIFO is easily read. Reading the least
significant byte of the SCSI Output Data Latch (SODL)
register causes the FIFO to unload. The functions are
summarized in the following table.
Register
Name
Register
Operation
FIFO Bits FIFO Function
SODL
SODL0
SODL1
Read
Read
Read
[15:0]
[7:0]
Unload
Unload
None
[15:8]
HSC
DSI
Halt SCSI Clock
Asserting this bit causes the internal divided SCSI clock
to come to a stop in a glitchless manner. This bit is used
for test purposes or to lower I
mode.
5
during a power-down
DD
Disable Single Initiator Response
4
If this bit is set, the SYM53C896 SCSI function ignores
all bus-initiated selection attempts that employ the
single initiator option from SCSI-1. In order to select the
SYM53C896 SCSI function while this bit is set, the
SYM53C896 SCSI function’s SCSI ID and the initiator’s
SCSI ID must both be asserted. Assert this bit in
SCSI-2 systems so that a single bit error on the SCSI bus
is not interpreted as a single initiator response.
S16
16-Bit System
3
If this bit is set, all devices in the SCSI system
implementation are assumed to be 16-bit. This causes
the SYM53C896 to always check the parity bit for SCSI
IDs 15–8 during bus-initiated selection or reselection,
assuming parity checking has been enabled. If an 8-bit
SCSI device attempts to select the SYM53C896 while
this bit is set, the SYM53C896 will ignore the selection
attempt. This is because the parity bit for IDs 15–8 will
not be driven. See the description of the Enable Parity
Checking bit in the SCSI Control Zero (SCNTL0) register
for more information.
SCSI Registers
4-97
TTM
Timer Test Mode
2
Asserting this bit facilitates testing of the selection
time-out, general purpose, and handshake-to-handshake
timers by greatly reducing all three time-out periods.
Setting this bit starts all three timers and if the respective
bits in the SCSI Interrupt Enable One (SIEN1) register are
asserted, the SYM53C896 SCSI function generates
interrupts at time-out. This bit is intended for internal
manufacturing diagnosis and should not be used.
CSF
Clear SCSI FIFO
1
Setting this bit causes the “full flags” for the SCSI FIFO
to be cleared. This empties the FIFO. This bit is
self-clearing. In addition to the SCSI FIFO pointers, the
SIDL, SODL, and SODR full bits in the SCSI Status Zero
(SSTAT0) and SCSI Status Two (SSTAT2) are cleared.
STW
SCSI FIFO Test Write
0
Setting this bit places the SCSI core into a test mode in
which the FIFO is easily read or written. While this bit is
set, writes to the least significant byte of the SCSI Output
Data Latch (SODL) register cause the entire word
contained in SODL to be loaded into the FIFO. These
functions are summarized in the following table.
Register
Name
Register
Operation
FIFO Bits FIFO Function
SODL
SODL0
SODL1
Write
Write
Write
[15:0]
[7:0]
Load
Load
None
[15:8]
Registers:0x50–0x51
SCSI Input Data Latch (SIDL)
Read Only
This register is used primarily for diagnostic testing, programmed I/O
operation, or error recovery. Data received from the SCSI bus can be
read from this register. Data can be written to the SCSI Output Data Latch
(SODL) register and then read back into the SYM53C896 by reading this
register to allow loopback testing. When receiving SCSI data, the data
flows into this register and out to the host FIFO. This register differs from
the SCSI Bus Data Lines (SBDL) register; SCSI Input Data Latch (SIDL)
contains latched data and the SCSI Bus Data Lines (SBDL) always
4-98
Registers
contains exactly what is currently on the SCSI data bus. Reading this
register causes the SCSI parity bit to be checked, and causes a parity
error interrupt if the data is not valid. The power-up values are
indeterminate.
Register: 0x52
SCSI Test Four (STEST4)
Read Only
7
6
5
LOCK
0
4
0
0
0
SMODE[1:0]
R
0
0
0
0
0
SMODE[1:0] SCSI Mode
These bits contain the encoded value of the SCSI
[7:6]
operating mode that is indicated by the voltage level
sensed at the DIFFSENS pin. The incoming SCSI signal
goes to a pair of analog comparators that determine the
voltage window of the DIFFSENS signal. These voltage
windows indicate LVD, SE, or HVD operation. The bit
values are defined in the following table.
Bits [7:6]
Operating Mode
00
01
Not Possible
HVD or powered down (for HVD mode, the
DIF bit must also be set)
10
11
SE
LVD SCSI
LOCK
Frequency Lock
5
This bit is used when enabling the SCSI clock quadrupler,
which allows the SYM53C896 to transfer data at Ultra2
SCSI rates. Poll this bit for a 1 to determine that the clock
quadrupler has locked to 160 MHz. For more information
on enabling the clock quadrupler, refer to the descriptions
of SCSI Test One (STEST1), bits 2 and 3.
R
Reserved
[4:0]
SCSI Registers
4-99
Register: 0x53
Reserved
Registers:0x54–0x55
SCSI Output Data Latch (SODL)
Read/Write
This register is used primarily for diagnostic testing or programmed I/O
operation. Data written to this register is asserted onto the SCSI data bus
by setting the Assert Data Bus bit in the SCSI Control One (SCNTL1)
register. This register is used to send data using programmed I/O. Data
flows through this register when sending data in any mode. It is also used
to write to the synchronous data FIFO when testing the chip. The
power-up value of this register is indeterminate.
Register: 0x56
Chip Control 0 (CCNTL0)
Read/Write
7
6
5
4
DISFC
0
3
x
2
x
1
DILS
0
0
DPR
0
ENPMJ PMJCTL ENNDJ
R
0
0
0
ENPMJ
Enable Phase Mismatch Jump
7
Upon setting this bit, any phase mismatches do not
interrupt but force a jump to an alternate location to
handle the phase mismatch. Prior to actually taking the
jump, the appropriate remaining byte counts and
addresses will be calculated such that they can be easily
stored to the appropriate memory location with the
SCRIPTS Store instruction.
In the case of a SCSI send, any data in the part will be
automatically cleared after being accounted for. In the
case of a SCSI receive, all data will be flushed out of the
part and accounted for prior to taking the jump. This
feature does not cover, however, the byte that may
appear in SCSI Wide Residue (SWIDE). This byte must be
flushed manually.
This bit also enables the flushing mechanism to flush
data during a data in phase mismatch in a more efficient
manner.
4-100
Registers
PMJCTL
Jump Control
6
This bit controls which decision mechanism is used when
jumping on phase mismatch. When this bit is cleared the
SYM53C896 will use jump address one Phase Mismatch
Jump Address 1 (PMJAD1) when the WSR bit is cleared
and jump address two Phase Mismatch Jump Address 2
(PMJAD2) when the WSR bit is set. When this bit is set
the SYM53C896 will use jump address one (PMJAD1) on
data out (data out, command, message out) transfers and
jump address two (PMJAD2) on data in (data in, status,
message in) transfers. Note that the phase referred to
here is the phase encoded in the block move SCRIPTS
instruction, not the phase on the SCSI bus that caused
the phase mismatch.
ENNDJ
Enable Jump On Nondata Phase Mismatches
This bit controls whether or not a jump is taken during a
nondata phase mismatch (i.e. message in, message out,
status, or command). When this bit is cleared, jumps will
only be taken on data in or data out phases and a phase
mismatch interrupt will be generated for all other phases.
When this bit is set, jumps will be taken regardless of the
phase in the block move. Note that the phase referred to
here is the phase encoded in the block move SCRIPTS
instruction, not the phase on the SCSI bus that caused
the phase mismatch.
5
DISFC
Disable Auto FIFO Clear
4
This bit controls whether or not the FIFO is automatically
cleared during a data out phase mismatch. When set,
data in the DMA FIFO as well as data in the SCSI Output
Data Latch (SODL) and SODR (a hidden buffer register
which is not accessible) registers will not be cleared after
calculations on them are complete. When cleared, the
DMA FIFO, SODL and SODR will automatically be
cleared. This bit also disables the enhanced flushing
mechanism.
R
Reserved
[3:2]
DILS
Disable Internal Load/Store
1
This bit controls whether or not Load/Store data transfers,
in which the source/destination is located in SCRIPTS
RAM, generate external PCI cycles.
SCSI Registers
4-101
If cleared, Load/Store data transfers of this type will NOT
generate PCI cycles, but will stay internal to the chip.
If set, Load/Store data transfers of this type will generate
PCI cycles.
DPR
Disable Pipe Req
0
This bit controls whether or not overlapped arbitration on
the PCI bit is performed by asserting PCI REQ/ for one
SCSI function while the other SCSI function is executing
a PCI cycle.
If set, overlapped arbitration will be disabled, and PCI
REQ/ will not be asserted during a PCI master cycle
being executed by this chip.
Register: 0x57
Chip Control 1 (CCNTL1)
Read/Write
7
ZMOD
0
6
0
4
0
3
2
1
0
R
0
DDAC 64TIMOD EN64TIBMV EN64DBMV
x
x
0
0
ZMOD
High Impedance Mode
7
Setting this bit causes the SYM53C896 SCSI function to
place all output and bidirectional pins except
MOE/_TESTOUT, into a high impedance state. When this
bit is set, the MOE/_TESTOUT pin becomes the output
pin for the connectivity test of the SYM53C896 signals in
the “AND-tree” test mode. In order to read data out of the
SYM53C896 SCSI function, this bit must be cleared. This
bit is intended for board-level testing only. Do not set this
bit during normal system operation.
Note:
Both SCSI functions need to set this bit for the High
Impedance Mode.
R
Reserved
[6:4]
3
DDAC
Disable Dual Address Cycle (DDAC)
When this bit is set, all 64-bit addressing as a master will
be disabled. No DACs will be generated by the
SYM53C896.
4-102
Registers
When this bit is cleared, the SYM53C896 will generate
DACs based on the master operation being performed
and the value of its associated selector register.
64TIMOD
64-bit Table Indirect Indexing Mode
2
When this bit is cleared, bits [24:28] of the first table entry
dword will select one of 22 possible selectors to be used
in a BMOV operation. When this bit is set, bits [24:31] of
the first table entry dword will be copied directly into DMA
Next Address 64 (DNAD64) to provide 40-bit addressing
capability. This bit will only function if the EN64TIBMV bit
is set.
Index Mode 0 (64TIMOD clear) table entry format:
Bits [31:29]
Bits [28:24]
Bits [23:0]
Reserved
Sel Index
Byte Count
Source/Destination Address
Index Mode 1 (64TIMOD set) table entry format:
Bits [31:24]
Bits [23:0]
Src/Dest Addr [39:32]
Byte Count
Source/Destination Address [31:0]
EN64TIBMV Enable 64-bit Table Indirect BMOV
Setting this bit enables 64-bit addressing for Table
1
Indirect BMOVs using the upper byte (bits [24:31]) of the
first dword of the table entry. When this bit is cleared
table indirect BMOVs will use the Static Block Move Selec-
tor (SBMS) register to obtain the upper 32 bits of the data
address.
EN64DBMV Enable 64-bit Direct BMOV
Setting this bit enables the 64-bit version of a direct
0
BMOV. When this bit is cleared direct BMOVs will use the
Static Block Move Selector (SBMS) register to obtain the
upper 32 bits of the data address.
SCSI Registers
4-103
Registers:0x58–0x59
SCSI Bus Data Lines (SBDL)
Read Only
This register contains the SCSI data bus status. Even though the SCSI
data bus is active low, these bits are active high. The signal status is not
latched and is a true representation of exactly what is on the data bus at
the time the register is read. This register is used when receiving data
using programmed I/O. This register can also be used for diagnostic
testing or in the low level mode. The power-up value of this register is
indeterminate.
If the chip is in the wide mode (SCSI Control Three (SCNTL3), bit 3 and
SCSI Test Two (STEST2), bit 2 are set) and SCSI Bus Data Lines (SBDL)
is read, both byte lanes are checked for parity regardless of phase. When
in a nondata phase, this will cause a parity error interrupt to be generated
because upper byte lane parity is invalid.
Registers:0x5A–0x5B
Reserved
Registers:0x5C–0x5F
Scratch Register B (SCRATCHB)
Read/Write
This is a general purpose user definable scratch pad register. Apart from
CPU access, only register read/write and memory moves directed at the
SCRATCH register will alter its contents. The power-up values are
indeterminate. A special mode of this register can be enabled by setting
the PCI Configuration Info Enable bit in the Chip Test Two (CTEST2)
register. If this bit is set, the Scratch Register B (SCRATCHB) returns bits
[31:13] of the SCRIPTS RAM PCI Base Address Register Two (SCRIPTS
RAM) in bits [31:13] of the SCRATCH B register when read. When read,
bits [12:0] of SCRATCH B will always return zeros in this mode. Writes
to the SCRATCH B register are unaffected. Resetting the PCI
Configuration Info Enable bit causes the SCRATCH B register to return
to normal operation.
4-104
Registers
Registers:0x60–0x9F
Scratch Registers C–R (SCRATCHC–SCRATCHR)
Read/Write
These are general purpose user definable scratch pad registers. Apart
from CPU access, only register read/write, memory moves and
Load/Stores directed at a SCRATCH register will alter its contents. The
power-up values are indeterminate.
SCSI Registers
4-105
4.3 64-Bit SCRIPTS Selectors
The following registers are used to hold the upper 32-bit addresses for
various SCRIPTS operations. When a particular type of SCRIPTS
operation is performed, one of the 6 selector registers below will be used
to generate a 64-bit address.
If the selector for a particular device operation is zero, then a standard
32-bit address cycle will be generated. If the selector value is nonzero,
then a DAC will be issued with the entire 64-bit address.
All selectors default to 0 (zero) with the exception of the 16 scratch
registers, these power-up in an indeterminate state and should be
initialized before they are used.
All selectors can be read/written using the Load/Store SCRIPTS
instruction, Memory-to-Memory Move, Read/Write SCRIPTS instruction
or CPU with SCRIPTS not running.
Note:
Crossing of selector boundaries in one memory operation
is not supported.
Registers:0xA0–0xA3
Memory Move Read Selector (MMRS)
Read/Write
Supplies AD[63:32] during data read operations for Memory-to-Memory
Moves and absolute address LOAD operations.
A special mode of this register can be enabled by setting the PCI
Configuration Info Enable bit in the Chip Test Two (CTEST2) register. If
this bit is set, the Memory Move Read Selector (MMRS) register returns
bits [63:32] of the memory mapped operating register, PCI Base Address
Register One (MEMORY), when read.
Writes to the MMRS register are unaffected. Clearing the PCI
Configuration Info Enable bit causes the MMRS register to return to
normal operation.
4-106
Registers
Registers:0xA4–0xA7
Memory Move Write Selector (MMWS)
Read/Write
Supplies AD[63:32] during data write operations during
Memory-to-Memory Moves and absolute address STORE operations.
A special mode of this register can be enabled by setting the PCI
Configuration Info Enable bit in the Chip Test Two (CTEST2) register. If
this bit is set, the MMWS register returns bits [63:32] of the SCRIPTS
RAM PCI Base Address Register Two (SCRIPTS RAM) in bits [31:0] of the
MMWS register when read.
Writes to the MMWS register are unaffected. Clearing the PCI
Configuration Info Enable bit causes the MMWS register to return to
normal operation.
Registers:0xA8–0xAB
SCRIPTS Fetch Selector (SFS)
Read/Write
Supplies AD[63:32] during SCRIPTS fetches and Indirect fetches
(excluding Table Indirect fetches). This register can be loaded
automatically using a 64-bit jump instruction.
A special mode of this register can be enabled by setting the PCI
Configuration Info Enable bit in the Chip Test Two (CTEST2) register. If
this bit is set, bits [16:23] of the SCRIPTS Fetch Selector (SFS) register
return the PCI Revision ID (Rev ID) register value and bits [0:15] return
the PCI Device ID register value when read.
Writes to the SCRIPTS Fetch Selector (SFS) register are unaffected.
Clearing the PCI Configuration Information Enable bit causes the SFS
register to return to normal operation.
Registers:0xAC–0xAF
DSA Relative Selector (DRS)
Read/Write
Supplies AD[63:32] during table indirect fetches and Load/Store Data
Structure Address (DSA) relative operations.
64-Bit SCRIPTS Selectors
4-107
Registers:0xB0–0xB3
Static Block Move Selector (SBMS)
Read/Write
Supplies AD[63:32] during block move operations, reads or writes. This
register is static and will not be changed when a 64-bit direct BMOV is
used.
Registers:0xB4–0xB7
Dynamic Block Move Selector (DBMS)
Read/Write
Supplies AD[63:32] during block move operations, reads or writes. This
register is used only during 64-bit direct BMOV instructions and will be
reloaded with the upper 32-bit data address upon execution of 64-bit
direct BMOVs.
Registers:0xB8–0xBB
DMA Next Address 64 (DNAD64)
Read/Write
This register holds the current selector being used in a given host
transaction. The appropriate selector is copied to this register prior to
beginning a host transaction.
Registers:0xBC–0xBF
Reserved
4-108
Registers
4.4 Phase Mismatch Jump Registers
Eight 32-bit registers contain the byte count and addressing information
required to update the direct, indirect, or table indirect BMOV instructions
with new byte counts and addresses. The eight register descriptions
follow.
All registers can be read/written using the Load/Store SCRIPTS
instructions, Memory-to-Memory Moves, read/write SCRIPTS
instructions, or the CPU with SCRIPTS not running.
Registers:0xC0–0xC3
Phase Mismatch Jump Address 1 (PMJAD1)
Read/Write
This register contains the 32-bit address that will be jumped to upon a
phase mismatch. Depending upon the state of the PMJCTL bit this
address will either be used during an outbound (data out, command,
message out) phase mismatch (PMJCTL = 0) or when the WSR bit is
cleared (PMJCTL = 1). It should be loaded with an address of a
SCRIPTS routine that will handle the updating of memory data structures
of the BMOV that was executing when the phase mismatch occurred.
Registers:0xC4–0xC7
Phase Mismatch Jump Address 2 (PMJAD2)
Read/Write
This register contains the 32-bit address that will be jumped to upon a
phase mismatch. Depending upon the state of the PMJCTL bit this
address will either be used during an inbound (data in, status, message
in) phase mismatch (PMJCTL = 0) or when the WSR bit is set
(PMJCTL = 1). It should be loaded with an address of a SCRIPTS
routine that will handle the updating of memory data structures of the
BMOV that was executing when the phase mismatch occurred.
Phase Mismatch Jump Registers
4-109
Registers:0xC8–0xCB
Remaining Byte Count (RBC)
Read/Write
This register contains the byte count that remains for the BMOV that was
executing when the phase mismatch occurred. In the case of direct or
indirect BMOV instructions, the upper byte of this register will also
contain the opcode of the BMOV that was executing. In the case of a
table indirect BMOV instruction, the upper byte will contain the upper
byte of the table indirect entry that was fetched.
In the case of a SCSI data receive, this byte count will reflect all data
received from the SCSI bus, including any byte in SCSI Wide Residue
(SWIDE). There will be no data remaining in the part that must be flushed
to memory with the exception of a possible byte in the SWIDE register.
That byte must be flushed to memory manually in SCRIPTS.
In the case of a SCSI data send, this byte count will reflect all data sent
out onto the SCSI bus. Any data left in the part from the phase mismatch
will be ignored and automatically cleared from the FIFOs.
Registers:0xCC–0xCF
Updated Address (UA)
Read/Write
This register will contain the updated data address for the BMOV that
was executing when the phase mismatch occurred.
In the case of a SCSI data receive, if there is a byte in the SCSI Wide
Residue (SWIDE) register then this address will point to the location
where that byte must be stored. The SWIDE byte must be manually
written to memory and this address must be incremented prior to
updating any scatter/gather entry.
In the case of a SCSI data receive, if there is not a byte in the SWIDE
register then this address will be the next location that should be written
to when this I/O restarts. No manual flushing will be necessary.
In the case of a SCSI data send, all data sent to the SCSI bus will be
accounted for and any data left in the part will be ignored and will be
automatically cleared from the FIFOs.
4-110
Registers
Registers:0xD0–0xD3
Entry Storage Address (ESA)
Read/Write
This register's value depends on the type of BMOV being executed. The
three types of BMOVs are.
Direct BMOV:
In the case of a direct BMOV, this register will contain
the address the BMOV was fetched from when the
phase mismatch occurred.
Indirect BMOV:
In the case of an indirect BMOV, this register will
contain the address the BMOV was fetched from when
the phase mismatch occurred.
Table Indirect BMOV: In the case of a table indirect BMOV, this register will
contain the address of the table indirect entry being
used when the phase mismatch occurred.
Registers:0xD4–0xD7
Instruction Address (IA)
Read/Write
This register always contains the address of the BMOV instruction that
was executing when the phase mismatch occurred. This value will always
match the value in the Entry Storage Address (ESA) except in the case
of a table indirect BMOV in which case the ESA will have the address of
the table indirect entry and this register will point to the address of the
BMOV instruction.
Registers:0xD8–0xDA
SCSI Byte Count (SBC)
Read Only
This register contains the count of the number of bytes transferred to or
from the SCSI bus during any given BMOV. This value is used in
calculating the information placed into the Remaining Byte Count (RBC)
and Updated Address (UA) registers and should not need to be used in
normal operations. There are two conditions in which this byte count will
not match the number of bytes transferred exactly. If a BMOV is executed
to transfer an odd number of bytes across a wide bus then the byte count
at the end of the BMOV will be greater than the number of bytes sent by
one. This will also happen in an odd byte count wide receive case. Also,
in the case of a wide send in which there is a chain byte from a previous
Phase Mismatch Jump Registers
4-111
transfer, the count will not reflect the chain byte sent across the bus
during that BMOV. The reason for this is due to the fact that to determine
the correct address to start fetching data from after a phase mismatch
this byte cannot be counted for this BMOV as it was actually part of the
byte count for the previous BMOV.
Register: 0xDB
Reserved
Registers:0xDC–0xDF
Cumulative SCSI Byte Count (CSBC)
Read/Write
This loadable register contains a cumulative count of the actual number
of bytes that have been transferred across the SCSI bus during data
phases, i.e. it will not count bytes sent in command, status, message in
or message out phases. It will count bytes as long as the phase
mismatch enable (ENPMJ) in the Chip Control 0 (CCNTL0) register is set.
Unlike the SCSI Byte Count (SBC) this count will not be cleared on each
BMOV instruction but will continue to count across multiple BMOV
instructions. This register can be loaded with any arbitrary start value.
Registers:0xE0–0xFF
Reserved
4-112
Registers
Chapter 5
SCSI SCRIPTS
Instruction Set
After power-up and initialization, the SYM53C896 can operate in the low
level register interface mode, or use SCSI SCRIPTS.
With the low level register interface, the user has access to the DMA
control logic and the SCSI bus control logic. An external processor has
access to the SCSI bus signals and the low level DMA signals, which
allow creation of complicated board level test algorithms. The low level
interface is useful for backward compatibility with SCSI devices that
require certain unique timings or bus sequences to operate properly.
Another feature allowed at the low level is loopback testing. In loopback
mode, the SCSI core can be directed to talk to the DMA core to test
internal data paths all the way out to the chip’s pins.
The following sections describe the benefits and use of SCSI SCRIPTS.
•
•
•
•
•
•
•
Section 5.1, “SCSI SCRIPTS”
Section 5.2, “Block Move Instructions”
Section 5.3, “I/O Instructions”
Section 5.4, “Read/Write Instructions”
Section 5.5, “Transfer Control Instructions”
Section 5.6, “Memory Move Instructions”
Section 5.7, “Load/Store Instructions”
5.1 SCSI SCRIPTS
To operate in the SCSI SCRIPTS mode, the SYM53C896 requires only
a SCRIPTS start address. The start address must be at a dword (four
byte) boundary. This aligns all the following SCRIPTS at a dword
boundary since all SCRIPTS are 8 or 12 bytes long. Instructions are
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
5-1
fetched until an interrupt instruction is encountered, or until an
unexpected event (such as a hardware error) causes an interrupt to the
external processor.
Once an interrupt is generated, the SYM53C896 halts all operations until
the interrupt is serviced. Then, the start address of the next SCRIPTS
instruction is written to the DMA SCRIPTS Pointer (DSP) register to
restart the automatic fetching and execution of instructions.
In the SCSI SCRIPTS mode the SYM53C896 is allowed to make
decisions based on the status of the SCSI bus, which frees the
microprocessor from servicing the numerous interrupts inherent in I/O
operations.
Given the rich set of SCSI oriented features included in the instruction
set, and the ability to re-enter the SCSI algorithm at any point, this high
level interface is all that is required for both normal and exception
conditions. Switching to the low level mode for error recovery is not
required.
The following types of SCRIPTS instructions are implemented in the
SYM53C896:
•
•
Block Move—used to move data between the SCSI bus and memory.
I/O or Read/Write—causes the SYM53C896 to trigger common SCSI
hardware sequences, or to move registers.
•
•
•
Transfer Control—allows SCRIPTS instructions to make decisions
based on real time SCSI bus conditions.
Memory Move—causes the SYM53C896 to execute block moves
between different parts of main memory.
Load/Store—provides a more efficient way to move data to/from
memory from/to an internal register in the chip without using the
Memory Move instruction.
Each instruction consists of two or three 32-bit words. The first 32-bit
word is always loaded into the DMA Command (DCMD) and DMA Byte
Counter (DBC) registers, the second into the DMA SCRIPTS Pointer Save
(DSPS) register. The third word, used only by Memory Move instructions,
is loaded into the Temporary (TEMP) shadow register. In an indirect I/O
or Move instruction, the first two 32-bit opcode fetches are followed by
one or two more 32-bit fetch cycles.
5-2
SCSI SCRIPTS Instruction Set
5.1.1 Sample Operation
The following example describes execution of a SCRIPTS Block Move
instruction.
•
•
•
The host CPU, through programmed I/O, gives the DMA SCRIPTS
Pointer (DSP) register (in the Operating register file) the starting
address in main memory that points to a SCSI SCRIPTS program
for execution.
Loading the DMA SCRIPTS Pointer (DSP) register causes the
SYM53C896 to fetch its first instruction at the address just loaded.
This fetch is from main memory or the internal RAM, depending on
the address.
The SYM53C896 typically fetches two dwords (64 bits) and decodes
the high-order byte of the first dword as a SCRIPTS instruction. If the
instruction is a Block Move, the lower three bytes of the first dword
are stored and interpreted as the number of bytes to move. The
second dword is stored and interpreted as the 32-bit beginning
address in main memory to which the move is directed.
•
•
For a SCSI send operation, the SYM53C896 waits until there is
enough space in the DMA FIFO to transfer a programmable size
block of data. For a SCSI receive operation, it waits until enough data
is collected in the DMA FIFO for transfer to memory. At this point,
the SYM53C896 requests use of the PCI bus again to transfer the
data.
When the SYM53C896 is granted the PCI bus, it executes (as a bus
master) a burst transfer (programmable size) of data, decrements the
internally stored remaining byte count, increments the address
pointer, and then releases the PCI bus. The SYM53C896 stays off
the PCI bus until the FIFO can again hold (for a write) or has
collected (for a read) enough data to repeat the process.
The process repeats until the internally stored byte count has reached
zero. The SYM53C896 releases the PCI bus and then performs another
SCRIPTS instruction fetch cycle, using the incremented stored address
maintained in the DMA SCRIPTS Pointer (DSP) register. Execution of
SCRIPTS instructions continues until an error condition occurs or an
interrupt SCRIPTS instruction is received. At this point, the SYM53C896
interrupts the host CPU and waits for further servicing by the host
system. It can execute independent Block Move instructions specifying
SCSI SCRIPTS
5-3
new byte counts and starting locations in main memory. In this manner,
the SYM53C896 performs scatter/gather operations on data without
requiring help from the host program, generating a host interrupt, or
programming of an external DMA controller.
Figure 5.1 SCRIPTS Overview
System Processor
Write DSP
S
y
System Memory
(or Internal RAM)
s
t
SCSI Initiator Write Example
e
m
select ATN0, alt_addr
Fetch
SCRIPTS
move 1, identify_msg_buf, when MSG_OUT
move 6, cmd_buf, when CMD
move 512, data_buf, when DATA_OUT
move 1, stat_in_buf, when STATUS
move 1, msg_in_buf, when MSG_IN
move SCNTL2 & 7F to SCNTL2
clear ACK
SCSI
Bus
SYM53C896
B
u
s
wait disconnect alt2
int 10
Data
Data Structure
Message Buffer
Command Buffer
Data Buffer
(Data is not fetched across system bus if
internal RAM is enabled.)
Status Buffer
5.2 Block Move Instructions
For Block Move instructions, bits 5 and 4 (SIOM and DIOM) in the DMA
Mode (DMODE) register determine whether the source/destination
address resides in memory or I/O space. When data is moved onto the
SCSI bus, SIOM controls whether that data comes from I/O or memory
space. When data is moved off of the SCSI bus, DIOM controls whether
that data goes to I/O or memory space.
5-4
SCSI SCRIPTS Instruction Set
5.2.1 First Dword
Figure 5.2 Block Move Instruction - First Dword
31
30
29
28
27
26
24 23
0
DCMD Register
TIA OPC
DBC Register
TC[23:0]
IT[1:0]
IA
SCSIP[2:0]
IT[1:0]
IA
Instruction Type-Block Move
[31:30]
29
Indirect Addressing
Direct
When this bit is cleared, user data is moved to or from
the 32-bit data start address for the Block Move
instruction. The value is loaded into the chip’s address
register and incremented as data is transferred. The
address of the data to move is in the second dword of
this instruction.
When the EN64DBMV bit in Chip Control 1 (CCNTL1) is
set, a third dword is fetched to provide the upper dword
of a 64-bit address. The upper dword address will be
fetched along with the instruction and loaded into the
Dynamic Block Move Selector (DBMS) register.
If the EN64DBMV bit is cleared, then the upper dword
address is pulled from the Static Block Move Selector
(SBMS) register.
The byte count and absolute address are as follows:
Command
Byte Count
Lower dword Address of Data
Upper dword address of data (EN64DBMV = 1)
Indirect
When set, the 32-bit user data start address for the Block
Move is the address of a pointer to the actual data buffer
address. The value at the 32-bit start address is loaded
into the chip’s DMA Next Address (DNAD) register using
a third dword fetch (4-byte transfer across the host
computer bus).
Block Move Instructions
5-5
Use the fetched byte count, but fetch the data address
from the address in the instruction.
If 64-bit addressing is desired, the upper dword of the
address is stored in the Static Block Move Selector
(SBMS) register. When the value in SBMS is 0x0, 32-bit
addressing is assumed.
.
Command
Byte Count
Address of Pointer to Data
Once the data pointer address is loaded, it is executed
as when the chip operates in the direct mode. This
indirect feature allows specification of a table of data
buffer addresses. Using the SCSI SCRIPTS compiler, the
table offset is placed in the SCRIPTS at compile time.
Then at the actual data transfer time, the offsets are
added to the base address of the data address table by
the external processor. The logical I/O driver builds a
structure of addresses for an I/O rather than treating each
address individually.
Note:
Using indirect and table indirect addressing simultaneously
is not permitted; use only one addressing method at a time.
TIA
Table Indirect
28
32-Bit Addressing
When this bit is set, the 24-bit signed value in the start
address of the move is treated as a relative displacement
from the value in the Data Structure Address (DSA)
register. Both the transfer count and the source/
destination address are fetched from this location.
Use the signed integer offset in bits [23:0] of the second
four bytes of the instruction, added to the value in the
Data Structure Address (DSA) register, to fetch first the
byte count and then the data address. The signed value
is combined with the data structure base address to
generate the physical address used to fetch values from
the data structure. Sign-extended values of all ones for
negative values are allowed, but bits [31:24] are ignored.
.
Command
Not Used
Don’t Care
Table Offset
5-6
SCSI SCRIPTS Instruction Set
Note:
Using indirect and table indirect addressing simultaneously
is not permitted; use only one addressing method at a time.
Prior to the start of an I/O, load the Data Structure
Address (DSA) register with the base address of the I/O
data structure. Any address on a dword boundary is
allowed.
After a Table Indirect opcode is fetched, the Data
Structure Address (DSA) is added to the 24-bit signed
offset value from the opcode to generate the address of
the required data; both positive and negative offsets are
allowed. A subsequent fetch from that address brings the
data values into the chip.
For a MOVE instruction, the 24-bit byte count is fetched
from system memory. Then the 32-bit physical address is
brought into the SYM53C896. Execution of the move
begins at this point.
SCRIPTS can directly execute operating system I/O data
structures, saving time at the beginning of an I/O
operation. The I/O data structure can begin on any dword
boundary and may cross system segment boundaries.
There are two restrictions on the placement of pointer
data in system memory:
•
The eight bytes of data in the MOVE instruction must
be contiguous, as shown below, and
•
Indirect data fetches are not available during
execution of a Memory-to-Memory DMA operation
.
00
Byte Count
Physical Data Address
64-Bit Addressing
If the enable 64-bit Table Indirect Block Move
(EN64TIBMV) bit is clear, then table indirect block moves
will remain as 2 dword opcodes plus a 2 dword table
entry and the upper 32 bits of the address will be pulled
from the Static Block Move Selector (SBMS) (which is
loaded manually) when doing data transfers during block
move operations.
Block Move Instructions
5-7
If the enable 64-bit Table Indirect Block Move
(EN64TIBMV) bit is set and the 64-bit Table Indirect Index
Mode (64TIMOD) bit is cleared, then bits [28:24] of the
first dword of the table entry (where the byte count is
located) will select one of the 16 scratch registers or any
of the six 64-bit selector registers (for a total of 22
selector choices) as a selector for the upper 32-bit
address. Please see the Table Indirect Index mode
mapping table for a breakdown of index values and the
corresponding registers selected. The selected address
will get loaded into the DMA Next Address 64 (DNAD64)
automatically.
Note:
If EN64TIBMV is set and 64TIMOD is set then bits [31:24]
of the first dword of the table entry (where the byte count
is located) will be loaded directly into DMA Next Address 64
(DNAD64) to provide a 40-bit address.
The format for the table indirect entries for each mode is
shown below. The table for Table Indirect block moves
upper 32-bit address locations summarizes the available
modes for table indirect block moves.
Index Mode 0 (64TIMOD clear) table entry format:
31
31
29 28
24 23
0
R
Sel Index
Byte Count
Source/Destination Address [31:0]
Index Mode 1 (64TIMOD set) table entry format:
24 23
0
Src/Dest Addr [39:32]
Byte Count
Source/Destination Address [31:0]
Table Indirect block moves upper 32-bit address
locations:
5-8
SCSI SCRIPTS Instruction Set
Upper 32 bit Data
Address Comes From
EN64TIBMV 64TIMOD
0
0
1
0
1
0
SBMS
SBMS
ScratchC–J, MMWS, MMRS, SFS,
DRS, SBMS, DBMS
1
1
1st Table Entry dword bits 24–31
(40-bit addressing only)
Table Indirect Index mode mapping:
Index Value
Selector Used
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
0x08
0x09
0x0A
0x0B
0x0C
0x0D
0x0E
0x0F
0x10
0x11
0x12
Scratch C
Scratch D
Scratch E
Scratch F
Scratch G
Scratch H
Scratch I
Scratch J
Scratch K
Scratch L
Scratch M
Scratch N
Scratch O
Scratch P
Scratch Q
Scratch R
MMRS
MMWS
SFS
Block Move Instructions
5-9
Index Value
Selector Used
0x13
0x14
DRS
SBMS
DBMS
0x15
0x16–0x1F
Illegal (will result in IID interrupt)
OPC
Opcode
27
This 1-bit field defines the instruction to execute as a
block move (MOVE).
Target Mode
OPC
Instruction Defined
0
1
MOVE/MOVE64
CHMOV/CHMOV64
The SYM53C896 verifies that it is connected to the SCSI
bus as a target before executing this instruction.
The SYM53C896 asserts the SCSI phase signals
(SMSG/, SC_D/, and SI_O/) as defined by the Phase
Field bits in the instruction.
If the instruction is for the command phase, the
SYM53C896 receives the first command byte and
decodes its SCSI Group Code.
•
•
If the SCSI Group Code is either Group 0,
Group 1, Group 2, or Group 5, then the SYM53C896
overwrites the DMA Byte Counter (DBC) register with
the length of the Command Descriptor Block: 6, 10, or
12 bytes.
If the Vendor Unique Enhancement 0 (VUE0) bit
(SCSI Control Two (SCNTL2), bit 1) is cleared and the
SCSI group code is a vendor unique code, the
SYM53C896 overwrites the DMA Byte Counter (DBC)
register with the length of the Command Descriptor
Block: 6, 10, or 12 bytes. If the VUE0 bit is set, the
SYM53C896 receives the number of bytes in the byte
count regardless of the group code.
5-10
SCSI SCRIPTS Instruction Set
•
If any other Group Code is received, the DMA Byte
Counter (DBC) register is not modified and the
SYM53C896 requests the number of bytes specified
in the DMA Byte Counter (DBC) register. If the DBC
register contains 0x000000, an illegal instruction
interrupt is generated.
The SYM53C896 transfers the number of bytes specified
in the DMA Byte Counter (DBC) register starting at the
address specified in the DMA Next Address (DNAD)
register. If the Opcode bit is set and a data transfer ends
on an odd byte boundary, the SYM53C896 stores the last
byte in the SCSI Wide Residue (SWIDE) register during a
receive operation. This byte is combined with the first
byte from the subsequent transfer so that a wide transfer
can complete.
If the SATN/ signal is asserted by the initiator or a parity
error occurred during the transfer, it is possible to halt the
transfer and generate an interrupt. The Disable Halt on
Parity Error or ATN bit in the SCSI Control One (SCNTL1)
register controls whether the SYM53C896 halts on these
conditions immediately, or waits until completion of the
current Move.
Initiator Mode
OPC
Instruction Defined
0
1
CHMOV/CHMOV64
MOVE/MOVE64
The SYM53C896 verifies that it is connected to the SCSI
bus as an initiator before executing this instruction.
The SYM53C896 waits for an unserviced phase to occur.
An unserviced phase is defined as any phase (with
SREQ/ asserted) for which the SYM53C896 has not yet
transferred data by responding with a SACK/.
The SYM53C896 compares the SCSI phase bits in the
DMA Command (DCMD) register with the latched SCSI
phase lines stored in the SCSI Status One (SSTAT1)
register. These phase lines are latched when SREQ/ is
asserted.
Block Move Instructions
5-11
If the SCSI phase bits match the value stored in the SCSI
Status One (SSTAT1) register, the SYM53C896 transfers
the number of bytes specified in the DMA Byte Counter
(DBC) register starting at the address pointed to by the
DMA Next Address (DNAD) register. If the opcode bit is
cleared and a data transfer ends on an odd byte
boundary, the SYM53C896 stores the last byte in the
SCSI Wide Residue (SWIDE) register during a receive
operation, or in the SCSI Output Data Latch (SODL)
register during a send operation. This byte is combined
with the first byte from the subsequent transfer so that a
wide transfer can complete.
If the SCSI phase bits do not match the value stored in
the SCSI Status One (SSTAT1) register, the SYM53C896
generates a phase mismatch interrupt and the instruction
is not executed.
During a Message-Out phase, after the SYM53C896 has
performed a select with Attention (or SATN/ is manually
asserted with a Set ATN instruction), the SYM53C896
deasserts SATN/ during the final SREQ/SACK/
handshake.
When the SYM53C896 is performing a block move for
Message-In phase, it does not deassert the SACK/ signal
for the last SREQ/SACK/ handshake. Clear the SACK/
signal using the Clear SACK I/O instruction.
SCSIP[2:0]
SCSI Phase
[26:24]
This 3-bit field defines the desired SCSI information
transfer phase. When the SYM53C896 operates in the
initiator mode, these bits are compared with the latched
SCSI phase bits in the SCSI Status One (SSTAT1)
register. When the SYM53C896 operates in the target
mode, it asserts the phase defined in this field. The
following table describes the possible combinations and
the corresponding SCSI phase.
5-12
SCSI SCRIPTS Instruction Set
MSG C_D I_O SCSI Phase
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
Data-Out
Data-In
Command
Status
Reserved-Out
Reserved-In
Message-Out
Message-In
TC[23:0]
Transfer Counter
[23:0]
This 24-bit field specifies the number of data bytes to be
moved between the SYM53C896 and system memory.
The field is stored in the DMA Byte Counter (DBC)
register. When the SYM53C896 transfers data to/from
memory, the DBC register is decremented by the number
of bytes transferred. In addition, the DMA Next Address
(DNAD) register is incremented by the number of bytes
transferred. This process is repeated until the DBC
register is decremented to zero. At this time, the
SYM53C896 fetches the next instruction.
If bit 28 is set, indicating table indirect addressing, this
field is not used. The byte count is instead fetched from
a table pointed to by the Data Structure Address (DSA)
register.
Block Move Instructions
5-13
5.2.2 Second Dword
Figure 5.3 Block Move Instruction - Second Dword
31
24 23
16 15
8
7
0
DSPS Register
Start Address
[31:0]
This 32-bit field specifies the starting address of the data
to move to/from memory. This field is copied to the DMA
Next Address (DNAD) register. When the SYM53C896
transfers data to or from memory, the DNAD register is
incremented by the number of bytes transferred.
When bit 29 is set, indicating indirect addressing, this
address is a pointer to an address in memory that points
to the data location. When bit 28 is set, indicating table
indirect addressing, the value in this field is an offset into
a table pointed to by the Data Structure Address (DSA).
The table entry contains byte count and address
information.
5.2.3 Third Dword
Figure 5.4 Block Move Instruction - Third Dword
31
24 23
16 15
8
7
0
DBMS Register
Start Address
[63:32]
This 32-bit field specifies the upper dword of a 64-bit
starting address of data to move to/from memory. This
field is copied to the Dynamic Block Move Selector (DBMS)
register. The EN64DBMV bit in the Chip Control 1
(CCNTL1) register must be set for this dword to be
fetched.
5-14
SCSI SCRIPTS Instruction Set
5.3 I/O Instructions
This section contains information about the I/O Instruction Register. It is
divided into First Dword and Second Dword.
5.3.1 First Dword
Figure 5.5 First 32-Bit Word of the I/O Instruction
31 30 29
DCMD Register
IT[1:0] OPC[2:0] RA TI Sel
27 26 25 24 23
20 19
16 15
11 10
9
8
7
6
5
4
3
2
0
DBC Register
CA TM
R
ENDID[3:0]
R
R
A
R
ATN
R
IT[1:0]
Instruction Type - I/O Instruction
Opcode
[31:30]
[29:27]
OPC[2:0]
The following Opcode bits have different meanings,
depending on whether the SYM53C896 is operating in
the initiator or target mode. Opcode selections 0b101–
0b111 are considered Read/Write instructions, and are
described Section 5.4, “Read/Write Instructions”.
Target Mode
OPC2 OPC1 OPC0 Instruction Defined
0
0
0
0
1
0
0
1
1
0
0
1
0
1
0
Reselect
Disconnect
Wait Select
Set
Clear
Reselect Instruction
The SYM53C896 arbitrates for the SCSI bus by asserting
the SCSI ID stored in the SCSI Chip ID (SCID) register. If
it loses arbitration, it tries again during the next available
arbitration cycle without reporting any lost arbitration
status.
If the SYM53C896 wins arbitration, it attempts to reselect
the SCSI device whose ID is defined in the destination ID
field of the instruction. Once the SYM53C896 wins
I/O Instructions
5-15
arbitration, it fetches the next instruction from the address
pointed to by the DMA SCRIPTS Pointer (DSP) register.
This way the SCRIPTS can move on to the next
instruction before the reselection completes. It continues
executing SCRIPTS until a SCRIPTS that requires a
response from the initiator is encountered.
If the SYM53C896 is selected or reselected before
winning arbitration, it fetches the next instruction from the
address pointed to by the 32-bit jump address field stored
in the DMA Next Address (DNAD) register. Manually set
the SYM53C896 to the initiator mode if it is reselected, or
to the target mode if it is selected.
Disconnect Instruction
The SYM53C896 disconnects from the SCSI bus by
deasserting all SCSI signal outputs.
Wait Select Instruction
If the SYM53C896 is selected, it fetches the next
instruction from the address pointed to by the DMA
SCRIPTS Pointer (DSP) register.
If reselected, the SYM53C896 fetches the next instruction
from the address pointed to by the 32-bit jump address
field stored in the DMA Next Address (DNAD) register.
Manually set the SYM53C896 to the initiator mode when
it is reselected.
If the CPU sets the SIGP bit in the Interrupt Status Zero
(ISTAT0) register, the SYM53C896 aborts the Wait Select
instruction and fetches the next instruction from the
address pointed to by the 32-bit jump address field stored
in the DMA Next Address (DNAD) register.
Set Instruction
When the SACK/ or SATN/ bits are set, the
corresponding bits in the SCSI Output Control Latch
(SOCL) register are set. Do not set SACK/ or SATN/
except for testing purposes. When the target bit is set,
the corresponding bit in the SCSI Control Zero (SCNTL0)
register is also set. When the carry bit is set, the
corresponding bit in the Arithmetic Logic Unit (ALU) is
set.
Note:
None of the signals are set on the SCSI bus in target mode.
5-16
SCSI SCRIPTS Instruction Set
Clear Instruction
When the SACK/ or SATN/ bits are cleared, the
corresponding bits are cleared in the SCSI Output Control
Latch (SOCL) register. Do not set SACK/ or SATN/ except
for testing purposes. When the target bit is cleared, the
corresponding bit in the SCSI Control Zero (SCNTL0)
register is cleared. When the carry bit is cleared, the
corresponding bit in the ALU is cleared.
Note:
None of the signals are cleared on the SCSI bus in the
target mode.
Initiator Mode
OPC2 OPC1 OPC0
Instruction Defined
Select
0
0
0
0
1
0
0
1
1
0
0
1
0
1
0
Wait Disconnect
Wait Reselect
Set
Clear
Select Instruction
The SYM53C896 arbitrates for the SCSI bus by asserting
the SCSI ID stored in the SCSI Chip ID (SCID) register. If
it loses arbitration, it tries again during the next available
arbitration cycle without reporting any lost arbitration
status.
If the SYM53C896 wins arbitration, it attempts to select
the SCSI device whose ID is defined in the destination ID
field of the instruction. Once the SYM53C896 wins
arbitration, it fetches the next instruction from the address
pointed to by the DMA SCRIPTS Pointer (DSP) register.
This way the SCRIPTS can move to the next instruction
before the selection completes. It continues executing
SCRIPTS until a SCRIPTS that requires a response from
the target is encountered.
If the SYM53C896 is selected or reselected before
winning arbitration, it fetches the next instruction from the
address pointed to by the 32-bit jump address field stored
I/O Instructions
5-17
in the DMA Next Address (DNAD) register. Manually set
the SYM53C896 to the initiator mode if it is reselected, or
to the target mode if it is selected.
If the Select with SATN/ field is set, the SATN/ signal is
asserted during the selection phase.
Wait Disconnect Instruction
The SYM53C896 waits for the target to perform a “legal”
disconnect from the SCSI bus. A “legal” disconnect
occurs when SBSY/ and SSEL/ are inactive for a
minimum of one Bus Free delay (400 ns), after the
SYM53C896 receives a Disconnect Message or a
Command Complete Message.
Wait Reselect Instruction
If the SYM53C896 is selected before being reselected, it
fetches the next instruction from the address pointed to
by the 32-bit jump address field stored in the DMA Next
Address (DNAD) register. Manually set the SYM53C896
to the target mode when it is selected.
If the SYM53C896 is reselected, it fetches the next
instruction from the address pointed to by the DMA
SCRIPTS Pointer (DSP) register.
If the CPU sets the SIGP bit in the Interrupt Status Zero
(ISTAT0) register, the SYM53C896 aborts the Wait
Reselect instruction and fetches the next instruction from
the address pointed to by the 32-bit jump address field
stored in the DMA Next Address (DNAD) register.
Set Instruction
When the SACK/ or SATN/ bits are set, the
corresponding bits in the SCSI Output Control Latch
(SOCL) register are set. When the target bit is set, the
corresponding bit in the SCSI Control Zero (SCNTL0)
register is also set. When the carry bit is set, the
corresponding bit in the ALU is set.
Clear Instruction
When the SACK/ or SATN/ bits are cleared, the
corresponding bits are cleared in the SCSI Output Control
Latch (SOCL) register. When the target bit is cleared, the
5-18
SCSI SCRIPTS Instruction Set
corresponding bit in the SCSI Control Zero (SCNTL0)
register is cleared. When the carry bit is cleared, the
corresponding bit in the ALU is cleared.
RA
Relative Addressing Mode
26
When this bit is set, the 24-bit signed value in the DMA
Next Address (DNAD) register is used as a relative
displacement from the current DMA SCRIPTS Pointer
(DSP) address. Use this bit only in conjunction with the
Select, Reselect, Wait Select, and Wait Reselect
instructions. The Select and Reselect instructions can
contain an absolute alternate jump address or a relative
transfer address.
TI
Table Indirect Mode
25
When this bit is set, the 24-bit signed value in the DMA
Byte Counter (DBC) register is added to the value in the
Data Structure Address (DSA) register, and used as an
offset relative to the value in the Data Structure Address
(DSA) register. The SCSI Control Three (SCNTL3) value,
SCSI ID, synchronous offset and synchronous period are
loaded from this address. Prior to the start of an I/O, load
the Data Structure Address (DSA) with the base address
of the I/O data structure. Any address on a dword
boundary is allowed. After a Table Indirect opcode is
fetched, the Data Structure Address (DSA) is added to the
24-bit signed offset value from the opcode to generate
the address of the required data. Both positive and
negative offsets are allowed. A subsequent fetch from
that address brings the data values into the chip.
SCRIPTS can directly execute operating system I/O data
structures, saving time at the beginning of an I/O
operation. The I/O data structure can begin on any dword
boundary and may cross system segment boundaries.
There are two restrictions on the placement of data in
system memory:
•
The I/O data structure must lie within the 8 Mbytes
above or below the base address.
•
An I/O command structure must have all four bytes
contiguous in system memory, as shown below. The
offset/period bits are ordered as in the SCSI Transfer
(SXFER) register. The configuration bits are ordered
as in the SCSI Control Three (SCNTL3) register.
I/O Instructions
5-19
Config
ID
Offset/period
00
Use this bit only in conjunction with the Select, Reselect,
Wait Select, and Wait Reselect instructions. It is allowable
to set bits 25 and 26 individually or in combination:
Bit 25
Bit 26
Direct
0
0
1
1
0
1
0
1
Table Indirect
Relative
Table Relative
Direct
Uses the device ID and physical address in the
instruction.
Command
ID
Not Used
Not Used
Absolute Alternate Address
Table Indirect
Uses the physical jump address, but fetches data using
the table indirect method.
Command
Table Offset
Absolute Alternate Address
Relative
Uses the device ID in the instruction, but treats the
alternate address as a relative jump.
Command
ID
Not Used
Not Used
Absolute Jump Offset
Table Relative
Treats the alternate jump address as a relative jump and
fetches the device ID, synchronous offset, and
synchronous period indirectly. The value in bits [23:0] of
5-20
SCSI SCRIPTS Instruction Set
the first four bytes of the SCRIPTS instruction is added
to the data structure base address to form the fetch
address.
Command
Table Offset
Alternate Jump Offset
Sel
Select with ATN/
24
This bit specifies whether SATN/ is asserted during the
selection phase when the SYM53C896 is executing a
Select instruction. When operating in the initiator mode,
set this bit for the Select instruction. If this bit is set on
any other I/O instruction, an illegal instruction interrupt is
generated.
R
Reserved
[23:20]
ENDID[3:0]
Encoded SCSI Destination ID
[19:16]
This 4-bit field specifies the destination SCSI ID for an I/O
instruction.
R
Reserved
[15:11]
CA
Set/Clear Carry
10
This bit is used in conjunction with a Set or Clear
instruction to set or clear the Carry bit. Setting this bit
with a Set instruction asserts the Carry bit in the ALU.
Clearing this bit with a Clear instruction deasserts the
Carry bit in the ALU.
TM
Set/Clear Target Mode
9
This bit is used in conjunction with a Set or Clear
instruction to set or clear the target mode. Setting this bit
with a Set instruction configures the SYM53C896 as a
target device (this sets bit 0 of the SCSI Control Zero
(SCNTL0) register). Clearing this bit with a Clear
instruction configures the SYM53C896 as an initiator
device (this clears bit 0 of the SCNTL0 register).
R
A
R
Reserved
[8:7]
6
Set/Clear SACK/
Reserved
[5:4]
I/O Instructions
5-21
ATN
Set/Clear SATN/
3
These two bits are used in conjunction with a Set or Clear
instruction to assert or deassert the corresponding SCSI
control signal. Bit 6 controls the SCSI SACK/ signal. Bit
3 controls the SCSI SATN/ signal.
The Set instruction is used to assert SACK/ and/or SATN/
on the SCSI bus. The Clear instruction is used to
deassert SACK/ and/or SATN/ on the SCSI bus. The
corresponding bit in the SCSI Output Control Latch
(SOCL) register will be set or cleared depending on the
instruction used.
Since SACK/ and SATN/ are initiator signals, they are not
asserted on the SCSI bus unless the SYM53C896 is
operating as an initiator or the SCSI Loopback Enable bit
is set in the SCSI Test Two (STEST2) register.
The Set/Clear SCSI ACK/, ATN/ instruction is used after
message phase Block Move operations to give the
initiator the opportunity to assert attention before
acknowledging the last message byte. For example, if the
initiator wishes to reject a message, it issues an Assert
SCSI ATN instruction before a Clear SCSI ACK
instruction.
R
Reserved
[2:0]
5.3.2 Second Dword
Figure 5.6 Second 32-Bit Word of the I/O Instruction
31
24 23
16 15
8
7
0
DSPS Register
SA
Start Address
[31:0]
This 32-bit field contains the memory address to fetch the
next instruction if the selection or reselection fails.
If relative or table relative addressing is used, this value
is a 24-bit signed offset relative to the current DMA
SCRIPTS Pointer (DSP) register value.
5-22
SCSI SCRIPTS Instruction Set
5.4 Read/Write Instructions
The Read/Write instruction supports addition, subtraction, and
comparison of two separate values within the chip. It performs the
desired operation on the specified register and the SCSI First Byte
Received (SFBR) register, then stores the result back to the specified
register or the SFBR. If the COM bit (DMA Control (DCNTL), bit 0) is
cleared, Read/Write instructions cannot be used.
5.4.1 First Dword
Figure 5.7 Read/Write Instruction - First Dword
31 30 29
27 26
24 23 22
16 15
8
7
6
0
DCMD Register
DBC Register
ImmD
IT[1:0] OPC[2:0] O[2:0] D8
A[6:0]
A7
R-Must be 0
IT[1:0]
Instruction Type - Read/Write Instruction
[31:30]
The Read/Write instruction uses operator bits [26:24] in
conjunction with the opcode bits to determine which
instruction is currently selected.
OPC[2:0]
Opcode
[29:27]
The combinations of these bits determine if the
instruction is a Read/Write or an I/O instruction. Opcodes
0b000 through 0b100 are considered I/O instructions.
O[2:0]
D8
Operator
[26:24]
These bits are used in conjunction with the opcode bits
to determine which instruction is currently selected. Refer
to Table 5.1 for field definitions.
Use data8/SFBR
23
When this bit is set, SCSI First Byte Received (SFBR) is
used instead of the data8 value during a Read-Modify-
Write instruction (see Table 5.1). This allows the user to
add two register values.
A[6:0]
Register Address - A[6:0]
[22:16]
It is possible to change register values from SCRIPTS in
read-modify-write cycles or move to/from SCSI First Byte
Received (SFBR) cycles. A[6:0] selects an 8-bit
source/destination register within the SYM53C896.
Read/Write Instructions
5-23
ImmD
A7
Immediate Data
This 8-bit value is used as a second operand in logical
and arithmetic functions.
[15:8]
Upper Register Address Line [A7]
7
This bit is used to access registers 0x80–0xFF.
R
Reserved
[6:0]
5.4.2 Second Dword
Figure 5.8 Read/Write Instruction - Second Dword
31
24 23
16 15
8
7
0
DSPS Register
DA
Destination Address
[31:0]
This field contains the 32-bit destination address where
the data is to move.
5.4.3 Read-Modify-Write Cycles
During these cycles the register is read, the selected operation is
performed, and the result is written back to the source register.
The Add operation is used to increment or decrement register values (or
memory values if used in conjunction with a Memory-to-Register Move
operation) for use as loop counters.
Subtraction is not available when SCSI First Byte Received (SFBR) is
used instead of data8 in the instruction syntax. To subtract one value
from another when using SFBR, first XOR the value to subtract
(subtrahend) with 0xFF, and add 1 to the resulting value. This creates the
2s compliment of the subtrahend. The two values are then added to
obtain the difference.
5.4.4 Move To/From SFBR Cycles
All operations are read-modify-writes as shown in Table 5.1. However,
two registers are involved, one of which is always the SCSI First Byte
Received (SFBR). The possible functions of this instruction are:
5-24
SCSI SCRIPTS Instruction Set
•
•
•
•
Write one byte (value contained within the SCRIPTS instruction) into
any chip register.
Move to/from the SCSI First Byte Received (SFBR) from/to any other
register.
Alter the value of a register with AND, OR, ADD, XOR, SHIFT LEFT,
or SHIFT RIGHT operators.
After moving values to the SCSI First Byte Received (SFBR), the
compare and jump, call, or similar instructions are used to check the
value.
•
A Move-to-SFBR followed by a Move-from-SFBR is used to perform
a register to register move.
Table 5.1
Read/Write Instructions
Opcode 111
Operator Read-Modify-Write
Opcode 110
Move to SFBR
Opcode 101
Move from SFBR
000
Move data into register.
Syntax: “Move data8 to
RegA”
Move data into SCSI First
Byte Received (SFBR)
register. Syntax: “Move
data8 to SFBR”
Move data into register.
Syntax: “Move data8 to
RegA”
0011
Shift register one bit to the Shift register one bit to the
left and place the result in left and place the result in
Shift the SFBR register one
bit to the left and place the
the same register. Syntax: the SCSI First Byte Received result in the register. Syntax:
“Move RegA SHL RegA”
(SFBR) register. Syntax:
“Move RegA SHL SFBR”
“Move SFBR SHL RegA”
010
011
100
OR data with register and OR data with register and
place the result in the same place the result in the SCSI place the result in the
OR data with SFBR and
register. Syntax: “Move
RegA | data8 to RegA”
First Byte Received (SFBR)
register. Syntax: “Move
RegA | data8 to SFBR”
register. Syntax: “Move
SFBR | data8 to RegA”
XOR data with register and XOR data with register and XOR data with SFBR and
place the result in the same place the result in the SCSI place the result in the
register. Syntax: “Move
First Byte Received (SFBR)
register. Syntax: “Move
SFBR XOR data8 to RegA”
RegA XOR data8 to RegA” register. Syntax: “Move
RegA XOR data8 to SFBR”
AND data with register and AND data with register and AND data with SFBR and
place the result in the same place the result in the SCSI place the result in the
register. Syntax: “Move
RegA & data8 to RegA”
First Byte Received (SFBR)
register. Syntax: “Move
RegA & data8 to SFBR”
register. Syntax: “Move
SFBR & data8 to RegA”
Read/Write Instructions
5-25
Table 5.1
Read/Write Instructions (Cont.)
Opcode 111
Operator Read-Modify-Write
Opcode 110
Move to SFBR
Opcode 101
Move from SFBR
1011
Shift register one bit to the Shift register one bit to the
right and place the result in right and place the result in bit to the right and place the
the same register. Syntax: the SCSI First Byte Received result in the register. Syntax:
Shift the SFBR register one
“Move RegA SHR RegA”
(SFBR) register. Syntax:
“Move RegA SHR SFBR”
“Move SFBR SHR RegA”
110
Add data to register without Add data to register without Add data to SFBR without
carry and place the result
in the same register.
Syntax: “Move RegA +
data8 to RegA”
carry and place the result in carry and place the result in
the SCSI First Byte Received the register. Syntax: “Move
(SFBR) register. Syntax:
“Move RegA + data8 to
SFBR”
SFBR + data8 to RegA”
111
Add data to register with
carry and place the result
in the same register.
Add data to register with
carry and place the result in and place the result in the
the SCSI First Byte Received register. Syntax: “Move
Add data to SFBR with carry
Syntax: “Move RegA +
data8 to RegA with carry” “Move RegA + data8 to
SFBR with carry”
(SFBR) register. Syntax:
SFBR + data8 to RegA with
carry”
1. Data is shifted through the Carry bit and the Carry bit is shifted into the data byte.
Miscellaneous Notes:
Substitute the desired register name or address for “RegA” in the syntax examples.
data8 indicates eight bits of data.
Use SFBR instead of data8 to add two register values.
5-26
SCSI SCRIPTS Instruction Set
5.5 Transfer Control Instructions
This section describes transfer control instructions for the First Dword,
Second Dword, and Third Dword.
5.5.1 First Dword
Figure 5.9 Transfer Control Instructions - First Dword
31 30 29
27 26
24 23 22 21 20 19 18 17 16 15
DBC Register
MC
8
7
0
DCMD Register
IT[1:0] OPC[2:0] SCSIP[2:0] RA
J
CT IF TF CD CP VP
DC
IT[1:0]
Instruction Type - Transfer Control
Instruction
[31:30]
[29:27]
OPC[2:0]
Opcode
This 3-bit field specifies the type of transfer control
instruction to execute. All transfer control instructions can
be conditional. They can be dependent on a true/false
comparison of the ALU Carry bit or a comparison of the
SCSI information transfer phase with the Phase field,
and/or a comparison of the First Byte Received with the
Data Compare field. Each instruction can operate in the
initiator or target mode.
OPC2
OPC1
OPC0
Instruction Defined
0
0
0
0
1
0
0
1
1
X
0
1
0
1
X
Jump
Call
Return
Interrupt
Reserved
Jump Instruction
The SYM53C896 can do a true/false comparison of the
ALU carry bit, or compare the phase and/or data as
defined by the Phase Compare, Data Compare and
True/False bit fields. If the comparisons are true, then it
loads the DMA SCRIPTS Pointer (DSP) register with the
contents of the DMA SCRIPTS Pointer Save (DSPS)
Transfer Control Instructions
5-27
register. The DSP register now contains the address of
the next instruction.
If the comparisons are false, the SYM53C896 fetches the
next instruction from the address pointed to by the DMA
SCRIPTS Pointer (DSP) register, leaving the instruction
pointer unchanged.
When the JUMP64 instruction is used, a third dword is
fetched and loaded into the SCRIPTS Fetch Selector
(SFS) register. Bit 22 indicates whether the jump is to a
32-bit address (0) or a 64-bit address (1). All
combinations of jumps are still valid for JUMP64.
Call Instruction
The SYM53C896 can do a true/false comparison of the
ALU carry bit, or compare the phase and/or data as
defined by the Phase Compare, Data Compare, and
True/False bit fields. If the comparisons are true, it loads
the DMA SCRIPTS Pointer (DSP) register with the
contents of the DMA SCRIPTS Pointer Save (DSPS)
register and that address value becomes the address of
the next instruction.
When the SYM53C896 executes a Call instruction, the
instruction pointer contained in the DMA SCRIPTS Pointer
(DSP) register is stored in the Temporary (TEMP) register.
Since the TEMP register is not a stack and can only hold
one dword, nested call instructions are not allowed.
If the comparisons are false, the SYM53C896 fetches the
next instruction from the address pointed to by the DMA
SCRIPTS Pointer (DSP) register and the instruction
pointer is not modified.
Return Instruction
The SYM53C896 can do a true/false comparison of the
ALU carry bit, or compare the phase and/or data as
defined by the Phase Compare, Data Compare, and
True/False bit fields. If the comparisons are true, it loads
the DMA SCRIPTS Pointer (DSP) register with the
contents of the DMA SCRIPTS Pointer Save (DSPS)
register. That address value becomes the address of the
next instruction.
5-28
SCSI SCRIPTS Instruction Set
When a Return instruction is executed, the value stored
in the Temporary (TEMP) register is returned to the DMA
SCRIPTS Pointer (DSP) register. The SYM53C896 does
not check to see whether the Call instruction has already
been executed. It does not generate an interrupt if a
Return instruction is executed without previously
executing a Call instruction.
If the comparisons are false, the SYM53C896 fetches the
next instruction from the address pointed to by the DMA
SCRIPTS Pointer (DSP) register and the instruction
pointer is not modified.
Interrupt Instruction
The SYM53C896 can do a true/false comparison of the
ALU carry bit, or compare the phase and/or data as
defined by the Phase Compare, Data Compare, and
True/False bit fields. If the comparisons are true, the
SYM53C896 generates an interrupt by asserting the IRQ/
signal.
The 32-bit address field stored in the DMA SCRIPTS
Pointer Save (DSPS) register can contain a unique
interrupt service vector. When servicing the interrupt, this
unique status code allows the Interrupt Service Routine
to quickly identify the point at which the interrupt
occurred.
The SYM53C896 halts and the DMA SCRIPTS Pointer
(DSP) register must be written to before starting any
further operation.
Interrupt-on-the-Fly Instruction
The SYM53C896 can do a true/false comparison of the
ALU carry bit or compare the phase and/or data as
defined by the Phase Compare, Data Compare, and
True/False bit fields. If the comparisons are true, and the
Interrupt-on-the-Fly bit Interrupt Status Zero (ISTAT0) bit 2)
is set, the SYM53C896 asserts the Interrupt-on-the-Fly
bit.
SCSIP[2:0]
SCSI Phase
[26:24]
This 3-bit field corresponds to the three SCSI bus phase
signals that are compared with the phase lines latched
when SREQ/ is asserted. Comparisons can be performed
to determine the SCSI phase actually being driven on the
Transfer Control Instructions
5-29
SCSI bus. The following table describes the possible
combinations and their corresponding SCSI phase.
These bits are only valid when the SYM53C896 is
operating in the initiator mode. Clear these bits when the
SYM53C896 is operating in the target mode.
MSG
C/D I/O
SCSI Phase
Data-Out
0
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
0
0
1
1
1
1
Data-In
Command
Status
Reserved-Out
Reserved-In
Message-Out
Message-In
RA
Relative Addressing Mode
23
When this bit is set, the 24-bit signed value in the DMA
SCRIPTS Pointer Save (DSPS) register is used as a
relative offset from the current DMA SCRIPTS Pointer
(DSP) address (which is pointing to the next instruction,
not the one currently executing). The relative mode does
not apply to Return and Interrupt SCRIPTS.
Jump/Call an Absolute Address
Start execution at the new absolute address.
Command
Condition Codes
Absolute Alternate Address
Jump/Call a Relative Address
Start execution at the current address plus (or minus) the
relative offset.
Command
Condition Codes
Don’t Care
Alternate Jump Offset
The SCRIPTS program counter is a 32-bit value pointing
to the SCRIPTS currently under execution by the
SYM53C896. The next address is formed by adding the
5-30
SCSI SCRIPTS Instruction Set
32-bit program counter to the 24-bit signed value of the
last 24 bits of the Jump or Call instruction. Because it is
signed (twos compliment), the jump can be forward or
backward.
A relative transfer can be to any address within a
16 Mbyte segment. The program counter is combined
with the 24-bit signed offset (using addition or
subtraction) to form the new execution address.
SCRIPTS programs may contain a mixture of direct
jumps and relative jumps to provide maximum versatility
when writing SCRIPTS. For example, major sections of
code can be accessed with far calls using the 32-bit
physical address, then local labels can be called using
relative transfers. If a SCRIPTS is written using only
relative transfers it does not require any run time
alteration of physical addresses, and can be stored in and
executed from a PROM.
J
32/64 Bit Jump
22
When this bit is cleared, the jump address is 32 bits wide.
When this bit is set, the jump address is 64 bits wide.
CT
Carry Test
21
When this bit is set, decisions based on the ALU carry bit
can be made. True/False comparisons are legal, but Data
Compare and Phase Compare are illegal.
IF
Interrupt-on-the-Fly
20
When this bit is set, the interrupt instruction does not halt
the SCRIPTS processor. Once the interrupt occurs, the
Interrupt-on-the-Fly bit (Interrupt Status Zero (ISTAT0) bit
2) is asserted.
TF
Jump If True/False
19
This bit determines whether the SYM53C896 branches
when a comparison is true or when a comparison is false.
This bit applies to phase compares, data compares, and
carry tests. If both the Phase Compare and Data
Compare bits are set, then both compares must be true
to branch on a true condition. Both compares must be
false to branch on a false condition.
Transfer Control Instructions
5-31
Result of
Compare
Bit 19
Action
0
0
1
1
False
Jump Taken
No Jump
True
False
True
No Jump
Jump Taken
CD
Compare Data
18
When this bit is set, the first byte received from the SCSI
data bus (contained in the SCSI First Byte Received
(SFBR) register) is compared with the Data to be
Compared Field in the Transfer Control instruction. The
Wait for Valid Phase bit controls when this compare
occurs. The Jump if True/False bit determines the
condition (true or false) to branch on.
CP
Compare Phase
17
When the SYM53C896 is in the initiator mode, this bit
controls phase compare operations. When this bit is set,
the SCSI phase signals (latched by SREQ/) are
compared to the Phase Field in the Transfer Control
instruction. If they match, the comparison is true. The
Wait for Valid Phase bit controls when the compare
occurs. When the SYM53C896 is operating in the target
mode and this bit is set it tests for an active SCSI SATN/
signal.
VP
Wait For Valid Phase
16
If the Wait for Valid Phase bit is set, the SYM53C896
waits for a previously unserviced phase before comparing
the SCSI phase and data.
If the Wait for Valid Phase bit is cleared, the SYM53C896
compares the SCSI phase and data immediately.
MC
Data Compare Mask
[15:8]
The Data Compare Mask allows a SCRIPTS to test
certain bits within a data byte. During the data compare,
if any mask bits are set, the corresponding bit in the SCSI
First Byte Received (SFBR) data byte is ignored. For
instance, a mask of 0b01111111 and data compare value
of 0b1XXXXXXX allows the SCRIPTS processor to
determine whether or not the high-order bit is set while
ignoring the remaining bits.
5-32
SCSI SCRIPTS Instruction Set
DC
Data Compare Value
[7:0]
This 8-bit field is the data compared against the SCSI
First Byte Received (SFBR) register. These bits are used
in conjunction with the Data Compare Mask Field to test
for a particular data value. If the COM bit (DMA Control
(DCNTL), bit 0) is cleared, the value in the SFBR register
may not be stable. In this case, do not use instructions
using this data compare value.
5.5.2 Second Dword
Figure 5.10 Transfer Control Instructions - Second Dword
31
24 23
16 15
8
7
0
DSPS Register
Jump Address
[31:0]
This 32-bit field contains the address of the next
instruction to fetch when a jump is taken. Once the
SYM53C896 fetches the instruction from the address
pointed to by these 32 bits, this address is incremented
by 4, loaded into the DMA SCRIPTS Pointer (DSP)
register and becomes the current instruction pointer.
5.5.3 Third Dword
Figure 5.11 Transfer Control Instructions - Third Dword
31
24 23
16 15
8
7
0
SFS Register (Used for JUMP64 Instruction)
JUMP64 Address
[31:0]
This 32-bit field contains the upper dword of a 64-bit
address of the next instruction to fetch when a JUMP64
is taken.
Transfer Control Instructions
5-33
5.6 Memory Move Instructions
For Memory Move instructions, bits 5 and 4 (SIOM and DIOM) in the
DMA Mode (DMODE) register determine whether the source or
destination addresses reside in memory or I/O space. By setting these
bits appropriately, data may be moved within memory space, within I/O
space, or between the two address spaces.
The Memory Move instruction is used to copy the specified number of
bytes from the source address to the destination address.
For memory moves where the data read is from the 64-bit address
space, the upper dword of the address resides in the Memory Move Read
Selector (MMRS) register. For memory moves where the data is written
to the 64-bit address space, the upper dword of the address resides in
the Memory Move Write Selector (MMWS) register.
Allowing the SYM53C896 to perform memory moves frees the system
processor for other tasks and moves data at higher speeds than available
from current DMA controllers. Up to 16 Mbytes may be transferred with
one instruction. There are two restrictions:
•
Both the source and destination addresses must start with the same
address alignment (A[1:0]) must be the same). If the source and
destination are not aligned, then an illegal instruction interrupt
occurs. For the PCI Cache Line Size register setting to take effect,
the source and destination must be the same distance from a cache
line boundary.
•
Indirect addresses are not allowed. A burst of data is fetched from
the source address, put into the DMA FIFO and then written out to
the destination address. The move continues until the byte count
decrements to zero, then another SCRIPTS is fetched from system
memory.
The DMA SCRIPTS Pointer Save (DSPS) and Data Structure Address
(DSA) registers are additional holding registers used during the Memory
Move. However, the contents of the Data Structure Address (DSA) register
are preserved.
5-34
SCSI SCRIPTS Instruction Set
5.6.1 First Dword
Figure 5.12 Memory Move Instructions - First Dword
31
29 28
25 24 23
NF
16 15
8
7
0
DCMD Register
DBC Register
TC[23:0]
IT[2:0]
R
IT[2:0]
R
Instruction Type - Memory Move
Reserved
[31:29]
[28:25]
These bits are reserved and must be zero. If any of these
bits are set, an illegal instruction interrupt occurs.
NF
No Flush
24
When this bit is set, the SYM53C896 performs a Memory
Move without flushing the prefetch unit. When this bit is
cleared, the Memory Move instruction automatically
flushes the prefetch unit. Use the No Flush option if the
source and destination are not within four instructions of
the current Memory Move instruction.
Note:
This bit has no effect unless the Prefetch Enable bit in the
DMA Control (DCNTL) register is set. For information on
SCRIPTS instruction prefetching, see
Chapter 2, "Functional Description".
TC[23:0]
Transfer Count
[23:0]
The number of bytes to transfer is stored in the lower 24
bits of the first instruction word.
5.6.2 Read/Write System Memory from a SCRIPTS
By using the Memory Move instruction, single or multiple register values
are transferred to or from system memory.
Because the SYM53C896 responds to addresses as defined in the Base
Address Register Zero (I/O) or Base Address Register One (MEMORY)
registers, it can be accessed during a Memory Move operation if the
source or destination address decodes to within the chip’s register space.
If this occurs, the register indicated by the lower seven bits of the address
is taken as the data source or destination. In this way, register values are
Memory Move Instructions
5-35
saved to system memory and later restored, and SCRIPTS can make
decisions based on data values in system memory.
The SCSI First Byte Received (SFBR) is not writable using the CPU, and
therefore not by a Memory Move. However, it can be loaded using
SCRIPTS Read/Write operations. To load the SFBR with a byte stored
in system memory, first move the byte to an intermediate SYM53C896
register (for example, a SCRATCH register), and then to the SCSI First
Byte Received (SFBR).
The same address alignment restrictions apply to register access
operations as to normal memory-to-memory transfers.
5.6.3 Second Dword
Figure 5.13 Memory Move Instructions - Second Dword
-
31
24 23
16 15
8
7
0
DSPS Register
DSPS Register
[31:0]
These bits contain the source address of the Memory
Move.
If the source address is in the 64-bit address space, the
bits will be contained in the Memory Move Read Selector
(MMRS) register.
31
24 23
16 15
8
7
0
MMRS Register
5.6.4 Third Dword
Figure 5.14 Memory Move Instructions - Third Dword
31
24 23
16 15
8
7
0
TEMP Register
5-36
SCSI SCRIPTS Instruction Set
TEMP Register
[31:0]
These bits contain the destination address for the
Memory Move.
If the destination address is in the 64-bit address space,
the bits will be contained in the Memory Move Write Selec-
tor (MMWS) register.
31
24 23
16 15
8
7
0
MMWS Register
5.7 Load/Store Instructions
The Load/Store instructions provide a more efficient way to move data
from/to memory to/from an internal register in the chip without using the
normal memory move instruction.
The load/store instructions are represented by two-dword opcodes. The
first dword contains the DMA Command (DCMD) and DMA Byte Counter
(DBC) register values. The second dword contains the DMA SCRIPTS
Pointer Save (DSPS) value. This is either the actual memory location of
where to load/store, or the offset from the Data Structure Address (DSA),
depending on the value of bit 28 (DSA Relative).
For load operations where the data is read from the 64-bit address
space, the upper dword of address resides in the Memory Move Read
Selector (MMRS) register. For store operations where the data is written
to the 64-bit address space, the upper dword of address resides in the
Memory Move Write Selector (MMWS) register.
A maximum of 4 bytes may be moved with these instructions. The
register address and memory address must have the same byte
alignment, and the count set such that it does not cross dword
boundaries. The memory address may not map back to the chip,
excluding RAM and ROM. If it does, a PCI read/write cycle occurs (the
data does not actually transfer to/from the chip), and the chip issues an
interrupt (Illegal Instruction Detected) immediately following.
Load/Store Instructions
5-37
Bits A1, A0
Number of Bytes Allowed to Load/Store
00
01
10
11
One, two, three or four
One, two, or three
One or two
One
The SIOM and DIOM bits in the DMA Mode (DMODE) register determine
whether the destination or source address of the instruction is in Memory
space or I/O space, as illustrated in the following table. The Load/Store
utilizes the PCI commands for I/O read and I/O write to access the I/O
space.
Bit
Source
Destination
SIOM (Load)
DIOM (Store)
Memory
Register
Register
Memory
5.7.1 First Dword
Figure 5.15 Load/Store Instruction - First Dword
31
29 28 27 26 25 24 23
DCMD Register
16 15
3
2
0
DBC Register
IT[2:0] DSA
R
NF LS
A[7:0]
R
BC
IT[2:0]
Instruction Type
[31:29]
These bits should be 0b111, indicating the Load/Store
instruction.
DSA
DSA Relative
28
When this bit is cleared, the value in the DMA SCRIPTS
Pointer Save (DSPS) is the actual 32-bit memory address
used to perform the Load/Store to/from. When this bit is
set, the chip determines the memory address to perform
the Load/Store to/from by adding the 24 bit signed offset
value in the DMA SCRIPTS Pointer Save (DSPS) to the
Data Structure Address (DSA).
5-38
SCSI SCRIPTS Instruction Set
R
Reserved
[27:26]
25
NF
No Flush (Store instruction only)
When this bit is set, the SYM53C896 performs a Store
without flushing the prefetch unit. When this bit is cleared,
the Store instruction automatically flushes the prefetch
unit. Use No Flush if the source and destination are not
within four instructions of the current Store instruction.
This bit has no effect on the Load instruction.
Note:
This bit has no effect unless the Prefetch Enable bit in the
DMA Control (DCNTL) register is set. For information on
SCRIPTS instruction prefetching, see
Chapter 2, "Functional Description".
LS
Load/Store
24
When this bit is set, the instruction is a Load. When
cleared, it is a Store.
A[7:0]
Register Address
[23:16]
A[7:0] selects the register to load/store to/from within the
SYM53C896.
R
Reserved
[15:3]
[2:0]
BC
Byte Count
This value is the number of bytes to load/store.
5.7.2 Second Dword
Figure 5.16 Load/Store Instructions - Second Dword
31
24 23
16 15
8
8
7
7
0
DSPS Register - Memory I/O Address/DSA Offset
31
24 23
16 15
0
MMRS/MMWS Register
Memory I/O Address / DSA Offset
[31:0]
This is the actual memory location of where to load/store,
or the offset from the Data Structure Address (DSA)
register value.
Load/Store Instructions
5-39
5-40
SCSI SCRIPTS Instruction Set
Chapter 6
Specifications
This chapter specifies the SYM53C896 electrical and mechanical
characteristics. It is divided into the following sections:
•
•
•
•
•
Section 6.1, “DC Characteristics”
Section 6.2, “TolerANT Technology Electrical Characteristics”
Section 6.3, “AC Characteristics”
Section 6.4, “PCI and External Memory Interface Timing Diagrams”
Section 6.5, “SCSI Timing Diagrams”
6.1 DC Characteristics
Table 6.1
Absolute Maximum Stress Ratings
Symbol Parameter
Min
Max1
Unit
Test Conditions
TSTG
VDD
VIN
Storage temperature
−55
−0.5
150
4.5
°C
V
–
–
–
–
Supply voltage
Input voltage
VSS −0.3
±150
–
VDD +0.3
–
V
2
ILP
Latch-up current
Electrostatic discharge
mA
V
ESD3
2 K
MIL-STD 883C,
Method 3015.7
1. Stresses beyond those listed above may cause permanent damage to the device. These are stress
ratings only; functional operation of the device at these or any other conditions beyond those
indicated in the Operating Conditions section of the manual is not implied.
2. −2 V < VPIN < 8 V.
3. SCSI pins only.
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
6-1
Table 6.2
Operating Conditions
Symbol Parameter
VDD Supply voltage
IDD
Supply current (dynamic)2
IDD-I/O LVD Mode Supply Current (dynamic)
Min
Max1
Unit
Test Conditions
3.13
–
3.47
200
600
V
–
mA
mA
–
–
RBIAS = 9.76 kΩ
VDD = 3.3 V
IDD
TA
Supply current (static)
–
0
–
1
mA
°C
–
–
–
Operating free air
70
20
θJA
Thermal resistance (junction to ambient air)
°C/W
1. Conditions that exceed the operating limits may cause the device to function incorrectly.
2. Core and analog supply only.
Table 6.3
Symbol
LVD Driver SCSI Signals—SD[15:0], SDP[1:0], SREQ/, SREQ2/, SACK/,
SACK2/, SMSG/, SIO/, SCD/, SATN/, SBSY/, SSEL/, SRST/
Parameter
Min
Max
Units
Test Conditions
IO+
IO−
IO+
IO−
IOZ
Source (+) current
Sink (−) current
Source (+) current
Sink (−) current
3-state leakage
−7
7
−13
13
mA
mA
mA
mA
µA
Asserted state
Asserted state
Negated state
Negated state
0, VDD = 3 max
3.5
−3.5
−20
6.5
−6.5
20
Note: VCM = 0.7–1.8 V (Common Mode, nominal ~1.2 V), RL = 0–110 Ω, Rbias = 9.76 kΩ.
Figure 6.1 LVD Driver
R
L
I +
2
O
+
V
CM
−
I −
O
R
L
2
6-2
Specifications
Table 6.4
Symbol
LVD Receiver SCSI Signals—SD[15:0], SDP[1:0], SREQ/, SREQ2/, SACK/,
SACK2/, SMSG/, SIO/, SCD/, SATN/, SBSY/, SSEL/, SRST/
Parameter
Min
Max
Units
Test Condition
VI
VI
LVD receiver voltage asserting
LVD receiver voltage negating
120
–
–
mV
mV
AC Test
−120
At Speed
Note: VCM = 0.7–1.8 V (Common Mode Voltage, nominal ~1.2 V).
Figure 6.2 LVD Receiver
+
V
I
+
+
2
−
V
CM
+
−
V
I
−
2
−
Table 6.5
A and B DIFFSENS SCSI Signals
Symbol Parameter
Min
Max
Unit
Test Conditions
VIH
VS
HVD sense voltage
2.4
0.7
5.0
1.9
0.5
10
V
V
Note 1
Note 1
LVD sense voltage
SE sense voltage
3-state leakage
VIL
IOZ
V
SS −0.3
V
Note 1
−10
µA
0 VDD = 3 Max
1. Functional test specified VIH/VIL for each mode.
Table 6.6
Input Capacitance
Symbol Parameter
Min
Max
Unit
Test Conditions
CI
Input capacitance of input pads
Input capacitance of I/O pads
–
–
7
pF
pF
Guaranteed by design
Guaranteed by design
CIO
15
DC Characteristics
6-3
Table 6.7
Symbol
Bidirectional Signals—GPIO0_FETCH/, GPIO1_MASTER/, GPIO2, GPIO3,
GPIO4, MAD[7:0]
1
Parameter
Min
Max
Unit
Test Conditions
VIH
VIL
Input high voltage
Input low voltage
Output high voltage
Output low voltage
3-state leakage
2.0
VSS −0.5
2.4 VDD
VSS
5.0
0.8
–
V
V
–
–
VOH
VOL
IOZ
V
−8 mA dynamic
8 mA dynamic
0, 5.25 V
–
0.4
10
V
−10
µA
µA
IPULL
Pull down current
+7.5
+75
1. For channels A and B (except MAD[7:0]).
1
Table 6.8
Symbol
Output Signals—MAS/[1:0], MCE/, MOE/_TESTOUT , MWE/, TDO
Parameter
Min
Max
Unit
Test Conditions
VOH
VOL
IOZ
Output high voltage
Output low voltage
3-state leakage
2.4 VDD
VSS
–
V
V
−4 mA dynamic
4 mA dynamic
0, 5.25 V
0.4
10
−10
µA
1. MOE/_TESTOUT is not tested for 3-state leakage. It cannot be 3-stated.
6-4
Specifications
Table 6.9
Symbol
Bidirectional Signals—AD[63:0], C_BE[7:0]/, FRAME/, IRDY/, TRDY/,
DEVSEL/, STOP/, PERR/, PAR, PAR64, REQ64/, ACK64/
Parameters
Min
Max
Unit Test Conditions
VIH
VIL
Input high voltage
0.5 VDD MAX
5.0
V
V
VDD 3 Max
VDD 3 Min
−500 µA
1500 µA
−2 mA
Input low voltage
−0.5
0.3 VDD MIN
VOH
VOL
VOH
VOL
IOZ
Output high voltage
0.9 VDD MIN
–
V
Output low voltage
–
0.1 VDD MIN
V
5 V TolerANT output high voltage
5 V TolerANT output low voltage
3-state leakage
2.4
–
–
0.55
10
V
V
6 mA
−10
7.5
µA
µA
0, 5.25 V
–
IPULL-DOWN Pull down current1
75
1. Pull-down text does not apply to AD[31:0] and C_BE[3:0]/.
Table 6.10 Input Signals—CLK, GNT/, IDSEL, INT_DIR, RST/, SCLK, TCK, TDI,
TEST_HSC, TEST_RST/, TMS
Symbol Parameters
Min
Max
Unit
Test Conditions
1
VIH
VIL
IIN
Input high voltage
0.5 VDD
−0.5
5.0
0.3 VDD
10
V
V
VDD Max
1
Input low voltage
3-state leakage
VDD Max
−10
µA
µA
0, 5.25 V
–
IPULL-UP Pull up current - only on INT_DIR
1.
−75
−7.5
3-state leakage low does not apply to TEST_RST/.
Pull-up spec does not apply to: SCLK, CLK, GNT/, IDSEL, and RST/.
TEST_HSC has a pull-down.
DC Characteristics
6-5
Table 6.11 Output Signals—INTA, INTB, ALT_INTA, ALT_INTB, REQ/
Symbol Parameters
Min
Max
Unit
Test Conditions
VOH
VOL
VOH
VOL
IOZ
Output high voltage
0.9 VDD
–
–
0.1 VDD
–
V
V
−500 µA
1500 µa
−2 mA
6 mA
Output low voltage
5 V TolerANT output high voltage
5 V TolerANT output low voltage
3-state leakage
2.4
V
–
0.55
10
V
−10
−75
µA
µA
0, 5.25 V
–
IPULL-UP Pull-up current1
−7.5
1. Pull-up test does not apply to REQ/.
Table 6.12 Output Signal—SERR/
Parameters
Symbol
Min
Max
Unit
Test Conditions
VOL
IOZ
Output low voltage
3-state leakage
–
0.1 VDD
10
V
1.5 mA
–
−10
µA
6-6
Specifications
6.2 TolerANT Technology Electrical Characteristics
1
Table 6.13 TolerANT Technology Electrical Characteristics for SE SCSI Signals
Symbol Parameter
Min
Max
Units
Test Conditions
2
VOH
VOL
VIH
VIL
Output high voltage
2.0
VSS
2.0
VDD +0.3
0.5
V
V
IOH = 7 mA
IOL = 48 mA
–
Output low voltage
Input high voltage
VDD +0.3
0.8
V
Input low voltage
VSS −0.3
−0.66
1.0
V
Referenced to VSS
VIK
Input clamp voltage
Threshold, HIGH to LOW
Threshold, LOW to HIGH
−0.77
1.2
V
VDD = 4.75; II = −20 mA
VTH
VTL
V
–
1.4
1.6
V
–
V
TH-VTL Hysteresis
300
500
mV
mA
mA
mA
–
2
IOH
Output high current
2.5
24
VOH = 2.5 V
VOL = 0.5 V
IOL
Output low current
100
200
2
IOSH
Short-circuit output high
current
–
625
Output driving low, pin shorted
to VDD supply3
IOSL
Short-circuit output low
current
–
–
–
95
20
mA Output driving high, pin shorted
to VSS supply
ILH
Input high leakage
µA
−0.5<VDD<VDD 5 Max
3
VPIN = VDD
ILL
Input low leakage
−20
µA
−0.5<VDD<VDD 5 Max
VPIN = 0 V
RI
Input resistance
20
–
–
MΩ
pF
SCSI pins4
PQFP
CP
Capacitance per pin
Rise time, 10% to 90%
Fall time, 90% to 10%
15
2
tR
4.0
4.0
0.15
0.15
18.5
18.5
0.50
0.50
ns
Figure 6.3
Figure 6.3
Figure 6.3
Figure 6.3
tF
ns
dVH/dt Slew rate LOW to HIGH
dVL/dt Slew rate HIGH to LOW
V/ns
V/ns
TolerANT Technology Electrical Characteristics
6-7
1
Table 6.13 TolerANT Technology Electrical Characteristics for SE SCSI Signals
Symbol Parameter
ESD Electrostatic discharge
Min
Max
Units
Test Conditions
2
100
20
10
5
–
–
KV
mA
ns
MIL-STD-883C; 3015-7
–
Latch-up
Filter delay
30
15
8
Figure 6.4
Figure 6.4
Figure 6.4
Figure 6.4
Ultra filter delay
Ultra2 filter delay
Extended filter delay
ns
ns
40
60
ns
1. These values are guaranteed by periodic characterization; they are not 100% tested on every
device.
2. Active negation outputs only: Data, Parity, SREQ/, SACK/. (Minus Pins) SCSI mode only.
3. Single pin only; irreversible damage may occur if sustained for one second.
4. SCSI RESET pin has 10 kΩ pull-up resistor.
Figure 6.3 Rise and Fall Time Test Condition
47 Ω
20 pF
+
2.5 V
−
Figure 6.4 SCSI Input Filtering
t1
REQ/ or ACK/ Input
VTH
Note: t is the input filtering period.
1
6-8
Specifications
Figure 6.5 Hysteresis of SCSI Receivers
1.1
1.3
1
0
1.5
1.7
Input Voltage (Volts)
Figure 6.6 Input Current as a Function of Input Voltage
+40
+20
14.4 V
8.2 V
0
-0.7 V
HI-Z
OUTPUT
ACTIVE
-20
-40
-4
0
4
8
12
16
Input Voltage (Volts)
TolerANT Technology Electrical Characteristics
6-9
Figure 6.7 Output Current as a Function of Output Voltage
0
100
80
-200
-400
-600
-800
60
40
20
0
0
1
2
3
4
5
0
1
2
3
4
5
Output Voltage (Volts)
Output Voltage (Volts)
6-10
Specifications
6.3 AC Characteristics
The AC characteristics described in this section apply over the entire
range of operating conditions (refer to Section 6.1, “DC Characteristics”).
Chip timing is based on simulation at worst case voltage, temperature,
and processing. Timing was developed with a load capacitance of 50 pF.
1
Table 6.14 External Clock
Symbol
Parameter
Min
Max
Units
t1
Bus clock cycle time
SCSI clock cycle time (SCLK)2
CLK LOW time3
30
25
10
6
DC
60
–
ns
ns
t2
t3
t4
ns
SCLK LOW time3
CLK HIGH time3
33
–
ns
12
10
1
ns
SCLK HIGH time3
CLK slew rate
33
–
ns
V/ns
V/ns
SCLK slew rate
1
–
1. Timing is for an external 40 MHz clock. A quadrupled 40 MHz clock is required for Ultra2 SCSI
operation.
2. This parameter must be met to ensure SCSI timing is within specification.
3. Duty cycle not to exceed 60/40.
Figure 6.8 External Clock
t
1
t
3
CLK, SCLK 1.4 V
t
2
t
4
AC Characteristics
6-11
Table 6.15 Reset Input
Symbol
Parameter
Min
Max
Units
t1
t2
t3
Reset pulse width
10
0
–
–
–
tCLK
ns
Reset deasserted setup to CLK HIGH
MAD setup time to CLK HIGH (for configuring
the MAD bus only)
20
ns
t4
MAD hold time from CLK HIGH (for configuring
the MAD bus only)
20
–
ns
Figure 6.9 Reset Input
CLK
t
2
t
1
RST/
t
t
4
3
Valid
Data
MAD*
*When enabled
Table 6.16 Interrupt Output
Symbol
Parameter
Min
Max
Units
t1
t2
t3
CLK HIGH to IRQ/ LOW
CLK HIGH to IRQ/ HIGH
IRQ/ deassertion time
2
2
3
11
11
–
ns
ns
CLK
Figure 6.10 Interrupt Output
t
t
t
1
2
3
IRQ/
CLK
6-12
Specifications
6.4 PCI and External Memory Interface Timing Diagrams
Figure 6.11 through Figure 6.34 represent signal activity when the
SYM53C896 accesses the PCI bus. This section includes timing
diagrams for access to three groups of memory configurations. The first
group applies to Target Timing. The second group applies to IInitiator
Timing. The third group applies to External Memory Timing.
Note:
Multiple byte accesses to the external memory bus
increase the read or write cycle by 11 clocks for each
additional byte.
Timing diagrams included in this section are:
•
Target Timing
–
–
–
–
PCI Configuration Register Read
PCI Configuration Register Write
Operating Register/SCRIPTS RAM Read, 32 and 64-bit
Operating Register/SCRIPTS RAM Write, 32 and 64-bit
•
Initiator Timing
–
–
–
–
–
–
Nonburst Opcode Fetch, 32-bit Address and Data
Burst Opcode Fetch, 32-bit Address and Data
Back to Back Read, 32-bit Address and Data
Back to Back Write, 32-bit Address and Data
Burst Read, 32 and 64-bit
Burst Write, 32 and 64-bit
•
External Memory Timing
–
–
–
External Memory Read
External Memory Write
Normal/Fast Memory (≥128 Kbytes) Single Byte Access Read
Cycle
–
Normal/Fast Memory (≥ 128 Kbytes) Single Byte Access Write
Cycle
PCI and External Memory Interface Timing Diagrams
6-13
–
–
Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte Access Read
Cycle
Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte Access Write
Cycle
–
–
–
–
Slow Memory (≥ 128 Kbytes) Read Cycle
Slow Memory (≥ 128 Kbytes) Write Cycle
64 Kbytes ROM Read Cycle
64 Kbytes ROM Write Cycle
6-14
Specifications
6.4.1 Target Timing
Table 6.17 PCI Configuration Register Read
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
7
0
–
–
–
ns
ns
ns
11
Figure 6.11 PCI Configuration Register Read
CLK
(Driven by System)
t
1
FRAME/
(Driven by System)
t
2
t
Addr In
CMD
3
t
1
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Data Out
t
2
t
2
t
1
C_BE[3:0]/
(Driven by Master)
Byte Enable
t
2
t
3
t
1
PAR
(Driven by Master-Addr;
SYM53C896-Data)
Out
In
t
2
t
2
IRDY/
(Driven by Master)
t
1
t
3
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
t
1
IDSEL
(Driven by Master)
t
2
PCI and External Memory Interface Timing Diagrams
6-15
Table 6.18 PCI Configuration Register Write
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
7
0
–
–
–
ns
ns
ns
11
Figure 6.12 PCI Configuration Register Write
CLK
(Driven by System)
t
1
FRAME/
(Driven by Master)
t
2
Addr In
CMD
t
1
t
t
2
1
AD[31:0]
(Driven by Master)
Data In
t
2
t
t
2
1
C_BE[3:0]/
(Driven by Master)
Byte Enable
t
2
t
1
PAR
t
2
(Driven by Master)
t
1
t
2
IRDY/
(Driven by Master)
t
3
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
t
1
IDSEL
(Driven by Master)
t
2
6-16
Specifications
Table 6.19 Operating Register/SCRIPTS RAM Read, 32-Bit
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
7
0
–
–
–
ns
ns
ns
11
Figure 6.13 Operating Registers/SCRIPTS RAM Read, 32-Bit
CLK
(Driven by System)
t
1
FRAME/
(Driven by Master)
t
2
Addr In
t
3
t
1
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Data
Out
t
2
t
1
C_BE[3:0]/
(Driven by Master)
CMD
Byte Enable
t
t
2
2
t
t
1
3
PAR
(Driven by Master-Addr;
SYM53C896-Data
In
Out
t
2
t
1
t
2
IRDY/
(Driven by Master)
t
3
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
PCI and External Memory Interface Timing Diagrams
6-17
Table 6.20 Operating Register/SCRIPTS RAM Read, 64-Bit
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
7
0
–
–
–
ns
ns
ns
11
Figure 6.14 Operating Register/SCRIPTS RAM Read, 64-Bit
CLK
(Driven by System)
t
t
1
2
REQ64/
(Driven by Master)
ACK64/
(Driven by SYM53C896)
t
t
2
1
FRAME/
(Driven by Master)
t
t
3
t
1
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Addr Addr
Lo Hi
Data
Out
t
2
t
t
1
1
C_BE[3:0]/
(Driven by Master)
Dual
Addr CMD
Bus
Byte Enable
t
2
2
t
1
AD[63:32]
(Driven by Master-Addr;
SYM53C896-Data)
Hi Addr
t
2
t
t
1
1
C_BE[7:4]/
(Driven by Master)
Bus CMD
Byte Enable
t
t
2
2
t
1
t
3
PAR; PAR64
(Driven by Master-Addr;
SYM53C896-Data
In
In
Out
t
2
IRDY/
(Driven by Master)
t
2
t
1
TRDY/
(Driven by SYM53C896)
t
3
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
t
3
6-18
Specifications
Table 6.21 Operating Register/SCRIPTS RAM Write, 32-Bit
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
7
0
–
–
–
ns
ns
ns
11
Figure 6.15 Operating Register/SCRIPTS RAM Write, 32-Bit
CLK
(Driven by System)
t
1
FRAME/
(Driven by Master)
t
2
Addr In
t
t
2
1
t
1
AD[31:0]
(Driven by Master)
Data In
t
2
t
1
C_BE[3:0]/
(Driven by Master)
CMD
Byte Enable
t
t
2
2
t
t
1
1
PAR
In
In
(Driven by Master)
t
t
2
2
IRDY/
(Driven by Master)
t
1
t
2
t
3
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
PCI and External Memory Interface Timing Diagrams
6-19
Table 6.22 Operating Register/SCRIPTS RAM Write, 64-Bit
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
7
0
–
–
–
ns
ns
ns
11
6-20
Specifications
Figure 6.16 Operating Register/SCRIPTS RAM Write, 64-Bit
CLK
(Driven by System)
t
1
REQ64/
(Driven by Master)
t
2
ACK64/
(Driven by SYM53C896)
t
1
FRAME/
(Driven by Master)
t
2
t
t
t
2
1
AD[31:0]
(Driven by Master)
Addr Addr
Lo Hi
Data In
t
2
t
t
1
1
C_BE[3:0]/
(Driven by Master)
Dual
Addr
Bus
CMD
t
Byte Enable
2
2
t
1
AD[63:32]
(Driven by Master)
Data
In
Hi Addr
t
t
1
1
C_BE[7:4]/
(Driven by Master)
Bus CMD
Byte Enable
t
t
2
2
t
1
t
1
PAR; PAR64
(Driven by Master)
In
In
In
t
t
2
2
IRDY/
(Driven by Master)
t
2
t
1
TRDY/
(Driven by SYM53C896)
t
3
STOP/
(Driven by SYM53C896)
DEVSEL/
(Driven by SYM53C896)
t
3
PCI and External Memory Interface Timing Diagrams
6-21
6.4.2 Initiator Timing
Table 6.23 Nonburst Opcode Fetch, 32-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
t4
t5
t6
t7
t8
t9
t10
Shared signal input setup time
Shared signal input hold time
7
0
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
CLK to shared signal output valid
Side signal input setup time
2
11
–
10
0
Side signal input hold time
–
CLK to side signal output valid
CLK HIGH to GPIO0_FETCH/ LOW
CLK HIGH to GPIO0_FETCH/ HIGH
CLK HIGH to GPIO1_MASTER/ LOW
CLK HIGH to GPIO1_MASTER/ HIGH
–
12
20
20
20
20
–
–
–
–
6-22
Specifications
Figure 6.17 Nonburst Opcode Fetch, 32-Bit Address and Data
CLK
(Driven by System)
REQ64/
(Driven by SYM53C896)
ACK64/
(Driven by SYM53C896)
t
7
GPIO0_FETCH/
(Driven by SYM53C896)
t
8
t
9
GPIO1_MASTER/
(Driven by SYM53C896)
t
10
REQ/
t
6
(Driven by SYM53C896)
GNT/
(Driven by Arbiter)
t
4
t
5
FRAME/
(Driven by SYM53C896)
t
3
Data
In
1
Data
In
t
AD[31:0]
(Driven by SYM53C896-
Addr; Target-Data)
Addr
Out
Addr
Out
t
2
t
3
C_BE[3:0]/
(Driven by SYM53C896)
Byte
Enable
Byte
Enable
CMD
CMD
t
t
3
1
PAR
(Driven by SYM53C896-
Addr; Target-Data)
t
3
t
2
IRDY/
t
3
(Driven by SYM53C896)
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
2
DEVSEL/
(Driven by Target)
t
1
PCI and External Memory Interface Timing Diagrams
6-23
Table 6.24 Burst Opcode Fetch, 32-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
t4
t5
t6
t7
t8
t9
t10
Shared signal input setup time
Shared signal input hold time
7
0
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
CLK to shared signal output valid
Side signal input setup time
2
11
–
10
0
Side signal input hold time
–
CLK to side signal output valid
CLK HIGH to GPIO0_FETCH/ LOW
CLK HIGH to GPIO0_FETCH/ HIGH
CLK HIGH to GPIO1_MASTER/ LOW
CLK HIGH to GPIO1_MASTER/ HIGH
–
12
20
20
20
20
–
–
–
–
6-24
Specifications
Figure 6.18 Burst Opcode Fetch, 32-Bit Address and Data
CLK
(Driven by System)
REQ64/
(Driven by SYM53C896)
ACK64/
(Driven by SYM53C896)
t
7
GPIO0_FETCH/
(Driven by SYM53C896)
t
8
t
9
GPIO1_MASTER/
t
10
(Driven by SYM53C896)
REQ/
t
6
(Driven by SYM53C896)
GNT/
(Driven by Arbiter)
t
4
t
5
FRAME/
(Driven by SYM53C896)
t
t
3
Data Data
t
t
1
3
In
In
AD[31:0]
(Driven by SYM53C896-
Addr; Target-Data)
Addr
Out
t
2
3
C_BE[3:0]/
(Driven by SYM53C896)
Byte
Enable
CMD
t
t
1
3
PAR
(Driven by SYM53C896-
Addr; Target-Data)
Out
In
In
t
t
3
2
IRDY/
t
3
(Driven by SYM53C896)
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
2
DEVSEL/
(Driven by Target)
t
1
PCI and External Memory Interface Timing Diagrams
6-25
Table 6.25 Back-to-Back Read, 32-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
Side signal input setup time
7
0
–
–
ns
ns
ns
ns
ns
ns
ns
ns
t3
2
11
–
t4
10
0
t5
Side signal input hold time
–
t6
CLK to side signal output valid
CLK HIGH to GPIO1_MASTER/ LOW
CLK HIGH to GPIO1_MASTER/ HIGH
–
12
20
20
t9
–
t10
–
6-26
Specifications
Figure 6.19 Back-to-Back Read, 32-Bit Address and Data
CLK
(Driven by System)
REQ64/
(Driven by SYM53C896)
ACK64/
(Driven by SYM53C896)
GPIO0_FETCH/
(Driven by SYM53C896)
t
9
GPIO1_MASTER/
(Driven by SYM53C896)
t
10
t
6
REQ/
(Driven by SYM53C896)
t
5
GNT/
(Driven by Arbiter)
t
4
FRAME/
(Driven by SYM53C896)
t
t
3
Data
In
1
Data
In
t
3
AD[31:0]
(Driven by SYM53C896-
Addr; Target-Data)
Addr
Out
Addr
Out
t
2
t
3
C_BE[3:0]/
(Driven by SYM53C896)
CMD
CMD
BE
BE
t
1
t
3
PAR
(Driven by SYM53C896-
Addr; Target-Data)
Out
Out
In
In
t
2
IRDY/
t
3
(Driven by SYM53C896)
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
2
DEVSEL/
(Driven by Target)
t
1
PCI and External Memory Interface Timing Diagrams
6-27
Table 6.26 Back-to-Back Write, 32-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
Side signal input setup time
7
0
–
–
ns
ns
ns
ns
ns
ns
ns
ns
t3
2
11
–
t4
10
0
t5
Side signal input hold time
–
t6
CLK to side signal output valid
CLK HIGH to GPIO1_MASTER/ LOW
CLK HIGH to GPIO1_MASTER/ HIGH
–
12
20
20
t9
–
t10
–
6-28
Specifications
Figure 6.20 Back-to-Back Write, 32-Bit Address and Data
CLK
(Driven by System)
REQ64/
(Driven by SYM53C896)
ACK64/
(Driven by SYM53C896)
GPIO0_FETCH/
(Driven by SYM53C896)
t
9
GPIO1_MASTER/
(Driven by SYM53C896)
t
10
t
6
REQ/
(Driven by SYM53C896)
t
5
GNT/
(Driven by Arbiter)
t
4
FRAME/
(Driven by SYM53C896)
t
t
3
t
3
t
3
1
AD[31:0]
(Driven by SYM53C896-
Addr; Target-Data)
Addr Data
Out Out
Addr Data
Out Out
t
2
t
3
t
3
C_BE[3:0]/
(Driven by SYM53C896)
CMD
CMD
BE
BE
t
t
3
3
PAR
(Driven by SYM53C896-
Addr; Target-Data)
t
3
IRDY/
(Driven by SYM53C896)
t
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
2
1
DEVSEL/
(Driven by Target)
PCI and External Memory Interface Timing Diagrams
6-29
Table 6.27 Burst Read, 32-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
t3
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
7
0
2
–
–
ns
ns
ns
11
6-30
Specifications
Figure 6.21 Burst Read, 32-Bit Address and Data
CLK
(Driven by System)
GPIO0_FETCH/
(Driven by SYM53C896)
GPIO1_MASTER/
(Driven by SYM53C896)
REQ/
(Driven by SYM53C896)
GNT/
(Driven by Arbiter)
FRAME/
(Driven by SYM53C896)
Data In
AD[31:0]
(Driven by SYM53C896-
Addr
Out
Addr; Target-Data)
t
3
C_BE[3:0]/
(Driven by SYM53C896)
CMD
BE
PAR
(Driven by SYM53C896-
Addr; Target-Data)
Out
In
In
IRDY/
(Driven by SYM53C896)
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
2
DEVSEL/
(Driven by Target)
PCI and External Memory Interface Timing Diagrams
6-31
Table 6.28 Burst Read, 64-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
Shared signal input setup time
Shared signal input hold time
7
0
2
–
–
–
ns
ns
ns
ns
t3
CLK to shared signal output valid
CLK HIGH to GPIO1_MASTER/ HIGH
11
20
t10
6-32
Specifications
Figure 6.22 Burst Read, 64-Bit Address and Data
CLK
(Driven by System)
GPIO0_FETCH/
(Driven by SYM53C896)
t
10
GPIO1_MASTER/
(Driven by SYM53C896)
REQ/
(Driven by SYM53C896)
GNT/
(Driven by Arbiter)
REQ64/
(Driven by SYM53C896)
t
2
ACK64/
(Driven by Target)
FRAME/
(Driven by SYM53C896)
Data In
AD[31:0]
(Driven by SYM53C896-
Addr; Target-Data)
Addr
Out Hi
Addr
Out Lo
t
3
C_BE[3:0]/
(Driven by SYM53C896)
Dual
Addr
Bus
CMD
BE
Data In
AD[63:32]
(Driven by SYM53C896-
Addr; Target-Data)
Hi Address
C_BE[7:4]/
(Driven by SYM53C896)
t
Bus CMD
In
BE
PAR; PAR64
(Addr drvn by 896;-
Data drvn by Target)
Out
In
In
t
1
IRDY/
(Driven by SYM53C896)
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
2
DEVSEL/
(Driven by Target)
PCI and External Memory Interface Timing Diagrams
6-33
Table 6.29 Burst Write, 32-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
Shared signal input setup time
Shared signal input hold time
7
0
2
–
–
–
ns
ns
ns
ns
t3
CLK to shared signal output valid
CLK HIGH to GPIO1_MASTER/ HIGH
11
20
t10
6-34
Specifications
Figure 6.23 Burst Write, 32-Bit Address and Data
CLK
(Driven by System)
GPIO0_FETCH/
(Driven by SYM53C896)
t
10
GPIO1_MASTER/
(Driven by SYM53C896)
REQ/
(Driven by SYM53C896)
GNT/
(Driven by Arbiter)
FRAME/
(Driven by SYM53C896)
AD[31:0]
(Driven by SYM53C896)
Addr
Out
Data
Out
Data
Out
C_BE[3:0]/
(Driven by SYM53C896)
CMD
BE
t
3
PAR
(Driven by SYM53C896)
IRDY/
(Driven by SYM53C896)
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
1
DEVSEL/
(Driven by Target)
t
2
PCI and External Memory Interface Timing Diagrams
6-35
Table 6.30 Burst Write, 64-Bit Address and Data
Symbol
Parameter
Min
Max
Unit
t1
t2
Shared signal input setup time
Shared signal input hold time
7
0
2
–
–
–
ns
ns
ns
ns
t3
CLK to shared signal output valid
CLK HIGH to GPIO1_MASTER/ HIGH
11
20
t10
6-36
Specifications
Figure 6.24 Burst Write, 64-Bit Address and Data
CLK
(Driven by System)
GPIO0_FETCH/
(Driven by SYM53C896)
t
10
GPIO1_MASTER/
(Driven by SYM53C896)
REQ/
(Driven by SYM53C896)
GNT/
(Driven by Arbiter)
REQ64/
(Driven by SYM53C896)
t
2
ACK64/
(Driven by Target)
t
1
FRAME/
(Driven by SYM53C896)
AD[31:0]
(Driven by SYM53C896)
Addr
Out Hi
Data
Out
Data
Out
Addr
Out Lo
t
3
C_BE[3:0]/
(Driven by SYM53C896)
Dual
Addr
Bus
CMD
BE
BE
AD[63:32]
(Driven by SYM53C896)
Data
Out
Data
Out
Hi Address
Bus CMD
t
C_BE[7:4]/
(Driven by SYM53C896)
BE
BE
PAR; PAR64
(Driven by SYM53C896)
t
3
IRDY/
(Driven by SYM53C896)
t
1
TRDY/
(Driven by Target)
t
2
STOP/
(Driven by Target)
t
2
DEVSEL/
(Driven by Target)
t
1
PCI and External Memory Interface Timing Diagrams
6-37
6.4.3 External Memory Timing
Table 6.31 External Memory Read
Symbol
Parameter
Min
Max
Unit
t1
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
Address setup to MAS/ HIGH
Address hold from MAS/ HIGH
MAS/ pulse width
7
0
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
t2
t3
–
11
–
t11
t12
t13
t14
t15
t16
t17
t19
25
15
25
160
205
100
0
–
–
MCE/ LOW to data clocked in
Address valid to data clocked in
MOE/ LOW to data clocked in
Data hold from address, MOE/, MCE/ change
Data setup to CLK HIGH
–
–
–
–
5
–
6-38
Specifications
Figure 6.25 External Memory Read
1
2
3
4
5
6
7
8
9
10
CLK
(Driven by System)
t
1
FRAME/
(Driven by Master)
t
2
t
1
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Addr
In
t
t
2
t
1
C_BE[3:0]/
(Driven by Master)
Byte Enable
CMD
2
t
1
PAR
(Driven by Master-Addr;
SYM53C896-Data)
In
t
2
t
1
IRDY/
(Driven by Master)
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
MAD
(Addr drvn by SYM53C896;
Data Driven by Memory)
High Order
Address
Middle Order
Address
Low Order
Address
t
11
t
12
t
13
MAS1/
(Driven by SYM53C896)
t
15
MAS0/
(Driven by SYM53C896)
MCE/
(Driven by SYM53C896)
MOE/
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
PCI and External Memory Interface Timing Diagrams
6-39
Figure 6.25 External Memory Read (Cont.)
11
12
13
14
15
16
17
18
19
20
21
CLK
(Driven by System)
FRAME/
(Driven by Master)
t
3
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Data
Out
C_BE[3:0]/
(Driven by Master)
t
2
t
3
PAR
(Driven by Master-Addr;
SYM53C896-Data)
Out
t
2
IRDY/
(Driven by Master)
t
3
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
t
19
MAD
(Addr drvn by SYM53C896;
Data Driven by Memory)
Data
In
t
17
MAS1/
(Driven by SYM53C896)
t
15
MAS0/
(Driven by SYM53C896)
t
14
MCE/
(Driven by SYM53C896)
t
MOE/
16
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
6-40
Specifications
Table 6.32 External Memory Write
Symbol
Parameter
Min
Max
Unit
t1
Shared signal input setup time
Shared signal input hold time
CLK to shared signal output valid
Address setup to MAS/ HIGH
Address hold from MAS/ HIGH
MAS/ pulse width
7
0
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
t2
t3
–
11
–
t11
t12
t13
t20
t21
t22
t23
t24
t25
t26
25
15
25
30
20
100
75
120
25
25
–
–
Data setup to MWE/ LOW
Data hold from MWE/ HIGH
MWE/ pulse width
–
–
–
Address setup to MWE/ LOW
MCE/ LOW to MWE/ HIGH
MCE/ LOW to MWE/ LOW
MWE/ HIGH to MCE/ HIGH
–
–
–
–
PCI and External Memory Interface Timing Diagrams
6-41
Figure 6.26 External Memory Write
1
2
3
4
5
6
7
8
9
10
CLK
(Driven by System)
t
1
FRAME/
(Driven by Master)
t
2
t
1
t
1
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Addr
In
Data In
t
2
t
1
C_BE[3:0]/
(Driven by Master)
Byte Enable
CMD
t
2
t
1
PAR
(Driven by Master-Addr;
SYM53C896-Data)
In
t
2
t
1
IRDY/
(Driven by Master)
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
t
3
DEVSEL/
(Driven by SYM53C896)
MAD
High Order
Address
Middle Order
Address
Low Order
Address
(Driven by SYM53C896)
t
11
t
12
t
13
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
MCE/
(Driven by SYM53C896)
MOE/
t20
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
t23
6-42
Specifications
Figure 6.26 External Memory Write (Cont.)
11
12
13
14
15
16
17
18
19
20
21
CLK
(Driven by System)
FRAME/
(Driven by Master)
t
2
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Data In
C_BE[3:0]/
(Driven by Master)
Byte Enable
t
1
2
t
PAR
(Driven by Master-Addr;
SYM53C896-Data)
In
t
2
t
2
IRDY/
(Driven by Master)
t
3
TRDY/
(Driven by SYM53C896)
t
3
STOP/
(Driven by SYM53C896)
DEVSEL/
(Driven by SYM53C896)
MAD
Data Out
(Driven by SYM53C896)
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
t
24
MCE/
(Driven by SYM53C896)
t
26
t
25
MOE/
(Driven by SYM53C896)
t
20
t
21
MWE/
(Driven by SYM53C896)
t
23
t
22
PCI and External Memory Interface Timing Diagrams
6-43
Table 6.33 Normal/Fast Memory (≥ 128 Kbytes) Single Byte Access Read Cycle
Symbol
Parameter
Min
Max
Unit
t11
t12
t13
t14
t15
t16
t17
t18
t19
Address setup to MAS/ high
Address hold from MAS/ high
MAS/ pulse width
25
15
25
160
205
100
0
–
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
MCE/ LOW to data clocked in
Address valid to data clocked in
MOE/ LOW to data clocked in
Data hold from address, MOE/, MCE/ change
Address out from MOE/, MCE/ HIGH
Data setup to CLK HIGH
50
5
Figure 6.27 Normal/Fast Memory (≥ 128 Kbytes) Single Byte Access Read Cycle
1
2
3
4
5
6
7
8
9
10
CLK
(Driven by System)
MAD
(Addr driven by SYM53C896;
Data Driven by Memory)
High Order
Address
Middle Order
Address
Low Order
Address
t
11
t
12
t
13
MAS1/
(Driven by SYM53C896)
t
15
MAS0/
(Driven by SYM53C896)
t
14
MCE/
(Driven by SYM53C896)
t
16
MOE/
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
6-44
Specifications
Figure 6.27 Normal/Fast Memory (≥ 128 Kbytes) Single Byte Access Read
Cycle (Cont.)
11
12
13
14
15
16
17
18
19
20
21
CLK
(Driven by System)
Valid
MAD
(Addr driven by SYM53C896;
Data Driven by Memory)
Read
Data
19
t
t
17
MAS1/
(Driven by SYM53C896)
t
15
MAS0/
(Driven by SYM53C896)
t
14
MCE/
(Driven by SYM53C896)
t
18
t
MOE/
16
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
PCI and External Memory Interface Timing Diagrams
6-45
Table 6.34 Normal/Fast Memory (≥ 128 Kbytes) Single Byte Access Write Cycle
Symbol
Parameter
Min
Max
Unit
t11
t12
t13
t20
t21
t22
t23
t24
t25
t26
Address setup to MAS/ HIGH
Address hold from MAS/ HIGH
MAS/ pulse width
25
15
–
–
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
25
Data setup to MWE/ LOW
Data hold from MWE/ HIGH
MWE/ pulse width
30
20
100
75
Address setup to MWE/ LOW
MCE/ LOW to MWE/ HIGH
MCE/ LOW to MWE/ LOW
MWE/ HIGH to MCE/ HIGH
120
25
25
Figure 6.28 Normal/Fast Memory (≥ 128 Kbytes) Single Byte Access Write Cycle
1
2
3
4
5
6
7
8
9
10
CLK
(Driven by System)
Valid
MAD
Middle Order
Address
High Order
Address
Low Order
Address
Write
Data
(Driven by SYM53C896)
t
t
11
12
t
13
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
t
24
MCE/
(Driven by SYM53C896)
t
25
MOE/
(Driven by SYM53C896)
t
20
MWE/
(Driven by SYM53C896)
t
23
6-46
Specifications
Figure 6.28 Normal/Fast Memory (≥ 128 Kbytes) Single Byte Access Write Cycle
(Cont.)
11
12
13
14
15
16
17
18
19
20
21
CLK
(Driven by System)
MAD
Valid Write Data
(Driven by SYM53C896)
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
t
t
t
26
24
MCE/
t
25
(Driven by SYM53C896)
MOE/
(Driven by SYM53C896)
t
20
21
MWE/
(Driven by SYM53C896)
t
23
t
22
PCI and External Memory Interface Timing Diagrams
6-47
Figure 6.29 Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte Access Read Cycle
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15
CLK
(Driven by System)
FRAME/
(Driven by Master)
Addr
AD[31:0]
(Driven by SYM53C896-
Master-Addr; Data)
In
CMD
C_BE[3:0]/
Byte Enable
(Driven by Master)
PAR
(Driven by SYM53C896-
Master-Addr;-Data)
In
IRDY/
(Driven by Master)
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
DEVSEL/
(Driven by SYM53C896)
Middle
Low
MAD
(Addr Driven by SYM53C896
Data Driven by Memory)
Order
Address
High Order
Address
Order
Address
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
MCE/
(Driven by SYM53C896)
MOE/
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
6-48
Specifications
Figure 6.29 Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte Access Read Cycle
(Cont.)
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
CLK
(Driven by System)
FRAME/
(Driven by Master)
Data Out
AD[31:0]
(Driven by SYM53C896-
Master-Addr; Data)
C_BE[3:0]/
(Driven by Master)
Byte Enable
PAR
(Driven by SYM53C896-
Master-Addr;-Data)
Out
IRDY/
(Driven by Master)
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
DEVSEL/
(Driven by SYM53C896)
Data In
Low Order
Address
Data In
MAD
(Addr Driven by SYM53C896
Data Driven by Memory)
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
MCE/
(Driven by SYM53C896)
MOE/
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
PCI and External Memory Interface Timing Diagrams
6-49
Figure 6.30 Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte Access Write Cycle
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15
CLK
(Driven by System)
FRAME/
(Driven by Master)
Addr
In
AD[31:0]
(Driven by Master-Addr;
SYM53C896-Data)
Data In
CMD
C_BE[3:0]/
Byte Enable
(Driven by Master)
PAR
(Driven by Master-Addr;
SYM53C896-Data)
In
IRDY/
(Driven by Master)
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
DEVSEL/
(Driven by SYM53C896)
Middle
Low
Order
Address
MAD
High Order
Address
Order
Address
Data Out
(Driven by SYM53C896)
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
MCE/
(Driven by SYM53C896)
MOE/
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
6-50
Specifications
Figure 6.30 Normal/Fast Memory (≥ 128 Kbytes) Multiple Byte Access Write Cycle
(Cont.)
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
CLK
(Driven by System)
FRAME/
(Driven by Master)
AD[31:0]
(Driven by Master-Addr;
Data In
SYM53C896-Data)
C_BE[3:0]/
(Driven by Master)
Byte Enable
PAR
(Driven by Master-Addr;
SYM53C896-Data)
In
IRDY/
(Driven by Master)
TRDY/
(Driven by SYM53C896)
STOP/
(Driven by SYM53C896)
DEVSEL/
(Driven by SYM53C896)
Low Order
Address
MAD
Data Out
(Driven by SYM53C896
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
MCE/
(Driven by SYM53C896)
MOE/
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
PCI and External Memory Interface Timing Diagrams
6-51
Table 6.35 Slow Memory (≥ 128 Kbytes) Read Cycle
Symbol
Parameter
Min
Max
Unit
t11
t12
t13
t14
t15
t16
t17
t18
t19
Address setup to MAS/ HIGH
Address hold from MAS/ HIGH
MAS/ pulse width
25
15
25
160
205
100
0
–
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
MCE/ LOW to data clocked in
Address valid to data clocked in
MOE/ LOW to data clocked in
Data hold from address, MOE/, MCE/ change
Address out from MOE/, MCE/ HIGH
Data setup to CLK HIGH
50
5
Figure 6.31 Slow Memory (≥ 128 Kbytes) Read Cycle
1
2
3
4
5
6
7
8
9
10
CLK
(Driven by System)
MAD
(Addr driven by SYM53C896
Data drvn by mem)
Middle Order
Address
High Order
Address
Low Order
Address
t
t
11
12
t
13
MAS1/
(Driven by SYM53C896)
t
15
MAS0/
(Driven by SYM53C896)
t
14
MCE/
(Driven by SYM53C896)
MOE/
t
16
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
6-52
Specifications
Figure 6.31 Slow Memory (≥ 128 Kbytes) Read Cycle (Cont.)
11
12
13
14
15
16
17
18
19
20
21
22
CLK
(Driven by System)
Valid
MAD
(Addr driven by SYM53C896;
Data Driven by Memory)
Read
Data
t
19
t
17
MAS1/
(Driven by SYM53C896)
t
15
MAS0/
(Driven by SYM53C896)
t
14
MCE/
(Driven by SYM53C896)
t
18
t
MOE/
16
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
PCI and External Memory Interface Timing Diagrams
6-53
Table 6.36 Slow Memory (≥ 128 Kbytes) Write Cycle
Symbol
Parameter
Min
Max
Unit
t11
t12
t13
t20
t21
t22
t23
t24
t25
t26
Address setup to MAS/ HIGH
Address hold from MAS/ HIGH
MAS/ pulse width
25
15
–
–
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
25
Data setup to MWE/ LOW
Data hold from MWE/ HIGH
MWE/ pulse width
30
20
100
75
Address setup to MWE/ LOW
MCE/ LOW to MWE/ HIGH
MCE/ LOW to MWE/ LOW
MWE/ HIGH to MCE/ HIGH
120
25
25
Figure 6.32 Slow Memory (≥ 128 Kbytes) Write Cycle
1
2
3
4
5
6
7
8
9
10
CLK
(Driven by System)
Valid
MAD
Middle Order
Address
High Order
Address
Low Order
Address
Write
Data
(Driven by SYM53C896)
t
t
11
12
t
13
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
t
24
MCE/
(Driven by SYM53C896)
t
25
MOE/
(Driven by SYM53C896)
t
20
MWE/
(Driven by SYM53C896)
t
23
6-54
Specifications
Figure 6.32 Slow Memory (≥ 128 Kbytes) Write Cycle (Cont.)
11
12
13
14
15
16
17
18
19
20
21
CLK
(Driven by System)
MAD
(Driven by SYM53C896)
Valid Write Data
MAS1/
(Driven by SYM53C896)
MAS0/
(Driven by SYM53C896)
t
t
24
26
MCE/
t
25
(Driven by SYM53C896)
MOE/
(Driven by SYM53C896)
t
20
t
21
t
22
MWE/
(Driven by SYM53C896)
t
23
PCI and External Memory Interface Timing Diagrams
6-55
Table 6.37 ≤ 64 Kbytes ROM Read Cycle
Symbol
Parameter
Min
Max
Unit
t11
t12
t13
t14
t15
t16
t17
t18
t19
Address setup to MAS/ HIGH
Address hold from MAS/ HIGH
MAS/ pulse width
25
15
25
160
205
100
0
–
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
MCE/ LOW to data clocked in
Address valid to data clocked in
MOE/ LOW to data clocked in
Data hold from address, MOE/, MCE/ change
Address out from MOE/, MCE/ HIGH
Data setup to CLK HIGH
50
5
Figure 6.33 ≤ 64 Kbytes ROM Read Cycle
1
2
3
4
5
6
7
8
9
10
11 12 13 14 15
CLK
(Driven by System)
Valid
MAD
(Addr driven by SYM53C896;
Data driven by Memory)
Read
Data
High Order
Address
Low Order
Address
t19
t12
t17
t11
MAS1/
(Driven by SYM53C896)
t15
t13
MAS0/
(Driven by SYM53C896)
t14
MCE/
(Driven by SYM53C896)
t18
t16
MOE/
(Driven by SYM53C896)
MWE/
(Driven by SYM53C896)
6-56
Specifications
Table 6.38 ≤ 64 Kbytes ROM Write Cycle
Symbol
Parameter
Min
Max
Unit
t11
t12
t13
t20
t21
t22
t23
t24
t25
t26
Address setup to MAS/ HIGH
Address hold from MAS/ HIGH
MAS/ pulse width
25
15
–
–
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
25
Data setup to MWE/ LOW
Data hold from MWE/ HIGH
MWE/ pulse width
30
20
100
75
Address setup to MWE/ LOW
MCE/ LOW to MWE/ HIGH
MCE/ LOW to MWE/ LOW
MWE/ HIGH to MCE/ HIGH
120
25
25
Figure 6.34 ≤ 64 Kbytes ROM Write Cycle
1
2
3
4
5
6
7
8
9
10
11 12 13
CLK
(Driven by System)
MAD
(Driven by SYM53C896)
High Order
Address
Low Order
Address
Valid Write Data
t
12
t
11
MAS1/
(Driven by SYM53C896)
t
13
MAS0/
(Driven by SYM53C896)
t
t
24
26
MCE/
(Driven by SYM53C896)
t
25
MOE/
(Driven by SYM53C896)
t
21
t
20
t
22
MWE/
(Driven by SYM53C896)
t
23
PCI and External Memory Interface Timing Diagrams
6-57
6.5 SCSI Timing Diagrams
Table 6.39 Initiator Asynchronous Send
Symbol
Parameter
Min
Max
Units
t1
t2
t3
t4
SACK/ asserted from SREQ/ asserted
SACK/ deasserted from SREQ/ deasserted
Data setup to SACK/ asserted
5
5
–
–
–
–
ns
ns
ns
ns
55
20
Data hold from SREQ/ deasserted
Figure 6.35 Initiator Asynchronous Send
SREQ/
n + 1
n
t
2
t
1
SACK/
n + 1
n
t
3
t
4
SD[15:0]/,
SDP[1:0]/
Valid n + 1
Valid n
Table 6.40 Initiator Asynchronous Receive
Symbol
Parameter
SACK/ asserted from SREQ/ asserted
Min
Max
Units
t1
t2
t3
t4
5
5
0
0
–
–
–
–
ns
ns
ns
ns
SACK/ deasserted from SREQ/ deasserted
Data setup to SREQ/ asserted
Data hold from SACK/ asserted
Figure 6.36 Initiator Asynchronous Receive
SREQ/
SACK/
t
n + 1
n
2
t
1
n + 1
n
t
3
t
4
SD[15:0]/,
SDP[1:0]/
Valid n + 1
Valid n
6-58
Specifications
Table 6.41 Target Asynchronous Send
Symbol
Parameter
Min
Max
Units
t1
t2
t3
t4
SREQ/ deasserted from SACK/ asserted
SREQ/ asserted from SACK/ deasserted
Data setup to SREQ/ asserted
5
5
–
–
–
–
ns
ns
ns
ns
55
20
Data hold from SACK/ asserted
Figure 6.37 Target Asynchronous Send
SREQ/
n
n + 1
t
2
t
1
SACK/
t
n + 1
n
3
t
4
SD[15:0]/,
SDP[1:0]/
Valid n + 1
Valid n
Table 6.42 Target Asynchronous Receive
Symbol
Parameter
Min
Max
Units
t1
t2
t3
t4
SREQ/ deasserted from SACK/ asserted
SREQ/ asserted from SACK/ deasserted
Data setup to SACK/ asserted
5
5
0
0
–
–
–
–
ns
ns
ns
ns
Data hold from SREQ/ deasserted
Figure 6.38 Target Asynchronous Receive
SREQ/
n
n + 1
t
2
t
1
SACK/
n + 1
n
t
3
t
4
SD[15:0]/,
SDP[1:0]/
Valid n
Valid n + 1
SCSI Timing Diagrams
6-59
Table 6.43 SCSI-1 Transfers (SE 5.0 Mbytes)
Symbol
Parameter
Min
Max
Units
t1
t2
t1
t2
t3
t4
t5
t6
Send SREQ/ or SACK/ assertion pulse width
Send SREQ/ or SACK/ deassertion pulse width
Receive SREQ/ or SACK/ assertion pulse width
Receive SREQ/ or SACK/ deassertion pulse width
Send data setup to SREQ/ or SACK/ asserted
Send data hold from SREQ/ or SACK/ asserted
Receive data setup to SREQ/ or SACK/ asserted
Receive data hold from SREQ/ or SACK/ asserted
90
90
90
90
55
100
0
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
45
Table 6.44 SCSI-1 Transfers (Differential 4.17 Mbytes)
Symbol
Parameter
Min
Max
Units
t1
t2
t1
t2
t3
t4
t5
t6
Send SREQ/ or SACK/ assertion pulse width
Send SREQ/ or SACK/ deassertion pulse width
Receive SREQ/ or SACK/ assertion pulse width
Receive SREQ/ or SACK/deassertion pulse width
Send data setup to SREQ/ or SACK/ asserted
Send data hold from SREQ/ or SACK/ asserted
Receive data setup to SREQ/ or SACK/ asserted
Receive data hold from SREQ/ or SACK/ asserted
96
96
84
84
65
110
0
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
45
6-60
Specifications
Table 6.45 SCSI-2 Fast Transfers 10.0 Mbytes (8-bit transfers) or
20.0 Mbytes (16-bit transfers) 40 MHz Clock
Symbol
Parameter
Min
Max
Units
t1
t2
t1
t2
t3
t4
t5
t6
Send SREQ/ or SACK/ assertion pulse width
Send SREQ/ or SACK/ deassertion pulse width
Receive SREQ/ or SACK/ assertion pulse width
Receive SREQ/ or SACK/ deassertion pulse width
Send data setup to SREQ/ or SACK/ asserted
Send data hold from SREQ/ or SACK/ asserted
Receive data setup to SREQ/ or SACK/ asserted
Receive data hold from SREQ/ or SACK/ asserted
35
35
20
20
33
45
0
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
10
Table 6.46 SCSI-2 Fast Transfers 10.0 Mbytes (8-bit transfers) or
1
20.0 Mbytes (16-bit transfers) 50 MHz Clock
Symbol
Parameter2
Min
Max
Unit
t1
t2
t1
t2
t3
t4
t5
t6
Send SREQ/ or SACK/ assertion pulse width
Send SREQ/ or SACK/ deassertion pulse width
Receive SREQ/ or SACK/ assertion pulse width
Receive SREQ/ or SACK/ deassertion pulse width
Send data setup to SREQ/ or SACK/ asserted
Send data hold from SREQ/ or SACK/ asserted
Receive data setup to SREQ/ or SACK/ asserted
Receive data hold from SREQ/ or SACK/ asserted
35
35
20
20
33
403
0
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
10
1. Transfer period bits (bits [6:4] in the SCSI Transfer (SXFER) register) are set to zero and the Extra
Clock Cycle of Data Setup bit (bit 7 in SCSI Control One (SCNTL1)) is set.
2. Note: for fast SCSI, set the TolerANT Enable bit (bit 7 in SCSI Test Three (STEST3)).
3. Analysis of system configuration is recommended due to reduced driver skew margin in differential
systems.
SCSI Timing Diagrams
6-61
Table 6.47 Ultra SCSI SE Transfers 20.0 Mbytes (8-bit transfers) or
40.0 Mbytes (16-bit transfers) Quadrupled 40 MHz Clock
1
Symbol
Parameter2
Min
Max
Unit
t1
t2
t1
t2
t3
t4
t5
t6
Send SREQ/ or SACK/ assertion pulse width
Send SREQ/ or SACK/ deassertion pulse width
Receive SREQ/ or SACK/ assertion pulse width
Receive SREQ/ or SACK/ deassertion pulse width
Send data setup to SREQ/ or SACK/ asserted
Send data hold from SREQ/ or SACK/ asserted
Receive data setup to SREQ/ or SACK/ asserted
Receive data hold from SREQ/ or SACK/ asserted
16
16
10
10
12
17
0
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
6
1. Transfer period bits (bits [6:4] in the SCSI Transfer (SXFER) register) are set to zero and the Extra
Clock Cycle of Data Setup bit (bit 7 in SCSI Control One (SCNTL1)) is set.
2. Note: for fast SCSI, set the TolerANT Enable bit (bit 7 in SCSI Test Three (STEST3)). During Ultra
SCSI transfers, the value of the Extend REQ/ACK Filtering bit (SCSI Test Two (STEST2), bit 1) has
no effect.
Table 6.48 Ultra SCSI HVD Transfers 20.0 Mbytes (8-bit transfers) or 40.0 Mbytes
1
(16-bit transfers) 80 MHz Clock
Symbol
Parameter2
Min
Max
Unit
t1
t2
t1
t2
t3
t4
t5
t6
Send SREQ/ or SACK/ assertion pulse width
Send SREQ/ or SACK/ deassertion pulse width
Receive SREQ/ or SACK/ assertion pulse width
Receive SREQ/ or SACK/ deassertion pulse width
Send data setup to SREQ/ or SACK/ asserted
Send data hold from SREQ/ or SACK/ asserted
Receive data setup to SREQ/ or SACK/ asserted
Receive data hold from SREQ/ or SACK/ asserted
16
16
10
10
16
21
0
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
6
1. Transfer period bits (bits [6:4] in the SCSI Transfer (SXFER) register) are set to zero and the Extra
Clock Cycle of Data Setup bit (bit 7 in SCSI Control One (SCNTL1)) is set.
2. During Ultra SCSI transfers, the value of the Extend REQ/ACK Filtering bit (SCSI Test Two
(STEST2), bit 1) has no effect.
6-62
Specifications
Table 6.49 Ultra2 SCSI Transfers 40.0 Mbyte (8-bit transfers) or
80.0 Mbyte (16-bit transfers) Quadrupled 40 MHz Clock
1
Symbol
Parameter2
Min
Max
Unit
t1
t2
t1
t2
t3
t4
t5
t6
Send SREQ/ or SACK/ assertion pulse width
Send SREQ/ or SACK/ deassertion pulse width
Receive SREQ/ or SACK/ assertion pulse width
Receive SREQ/ or SACK/ deassertion pulse width
Send data setup to SREQ/ or SACK/ asserted
Send data hold from SREQ/ or SACK/ asserted
Receive data setup to SREQ/ or SACK/ asserted
Receive data hold from SREQ/ or SACK/ asserted
8
8
–
–
–
–
–
–
–
–
ns
ns
ns
ns
ns
ns
ns
ns
6
6
10
10
4.5
4.5
1. Transfer period bits (bits [6:4] in the SCSI Transfer (SXFER) register) are set to zero and the Extra
Clock Cycle of Data Setup bit (bit 7 in SCSI Control One (SCNTL1)) is set.
2. During Ultra2 SCSI transfers, the value of the Extend REQ/ACK Filtering bit (SCSI Test Two
(STEST2), bit 1) has no effect.
Figure 6.39 Initiator and Target Synchronous Transfer
t
t
1
2
SREQ/
or SACK/
n + 1
n
t
t
3
4
Send Data
SD[15:0]/,
SDP[1:0]/
Valid n
Valid n + 1
t
6
t
5
Receive Data
SD[15:0]/,
Valid n
Valid n + 1
SDP[1:0]/
SCSI Timing Diagrams
6-63
Table 6.50 Signal Names and BGA Position
Signal
Name
BGA Signal
Pos Name
BGA Signal
Pos Name
BGA Signal
Pos Name
BGA Signal
Pos Name
BGA
Pos
AD0
A20
Y3 B_GPIO0_FETCH/AA14 C_BE3/
K1
AC4
AB4
AC3
AA4
H3
VDD
P20
K20
G20
Y17
Y14
Y10
Y7
A_DIFFSENS
A-GPIO0_
FETCH/
AD1
AA1 B_GPIO1_
Y2 MASTER/
Y1 B_GPIO2
W3 B_GPIO3
W4 B_GPIO4
W2 B_SACK−
W1 B_SACK+
V4 B_SACK2−
V2 B_SACK2+
V1 B_SATN−
U3 B_SATN+
U2 B_SBSY−
U1 B_SBSY+
T3 B_SC_D−
T4 B_SC_D+
N3 B_SD0−
C_BE4/
AC15 C_BE5/
AB15 C_BE6/
AA15 C_BE7/
AC16 CLK
N20 DEVSEL/
P21 FRAME/
P23 GNT/
P22 IDSEL
M23 INT_DIR
N22 INTA/
N23 INTB/
N21 IRDY/
VDD
AD2
VDD
AB16
AD3
AD4
VDD
A_GPIO1_
MASTER/Y16
A_GPIO2
A_GPIO3
A_GPIO4
A_SACK−
A_SACK+
A_SACK2−
A_SACK2+
A_SATN−
A_SATN+
A_SBSY−
A_SBSY+
A_SC_D−
A_SC_D+
A_SD0−
VDD
AD5
VDD
AA16
AD6
R1
VDD
AC17
AD7
P2
VDD
U4
AB17
AD8
C13
H4
VDD
P4
AD9
A14
L3
VDD
K4
AD10
B13
G2
VDD
G4
AD11
A13
F4
VDD
D17
D7
AD12
B11
F2
VDD
AD13
B12
N4
VDD
D14
C20
M22
A11
D3
AD14
C12
T20 MAD0
T21 MAD[1]
G21 MAD[2]
G22 MAD[3]
G23 MAD[4]
H21 MAD[5]
H20 MAD[6]
H22 MAD[7]
H23 MAS0/
J21 MAS1/
J20 MCE/
AC23
AB21
AC22
AA20
AB20
AC20
AA19
Y19
AC18
AA17
AA18
VDD-A
VDD-BIAS
VDD-BIAS2
VDD-CORE
VDD-CORE
VDD-CORE
VDD-CORE
VSS
AD15
A12
AD16
C15
AD17
A16
N1 B_SD0+
AD18
B6
N2 B_SD1−
E4
AD19
A6
M2 B_SD1+
Y13
AB18
D20
M4
A_SD0+
AD20
C7
M3 B_SD2−
A_SD1−
AD21
B7
M1 B_SD2+
A_SD1+
AD22
A7
L2 B_SD3−
VSS
A_SD2−
AD23
C8
L1 B_SD3+
VSS
Y4
A_SD2+
AD24
D8
K2 B_SD4−
VSS
Y12
Y20
M20
AA3
AA21
D12
D4
A_SD3−
AD25
B8
L4 B_SD4+
J22 MOE/_TESTOUT Y18
VSS
A_SD3+
AD26
A8
K3 B_SD5−
J23 MWE/
K21 NC
AC19
A1
A2
A22
A23
B1
B2
B3
B21
B22
B23
C2
C22
D21
AC1
AA22
AC2
AB2
AB22
AB23
AB3
T1
VSS
A_SD4−
AD27
C9
J1 B_SD5+
VSS
A_SD4+
AD28
D9
J2 B_SD6−
L20 NC
VSS
A_SD5−
AD29
B9
J4 B_SD6+
K22 NC
VSS
A_SD5+
AD30
A9
J3 B_SD7−
K23 NC
VSS
A_SD6−
AD31
C10
H1 B_SD7+
L21 NC
VSS
K10
K11
K12
K13
K14
L10
L11
L12
L13
L14
C21
C3
M10
M11
M12
M13
M14
N10
N11
N12
N13
N14
P10
P11
P12
P13
P14
B20
D2
A_SD6+
AD32
D11
AC14 B_SD8−
AA13 B_SD8+
AC13 B_SD9−
AB13 B_SD9+
AB12 B_SD10−
AA12 B_SD10+
AC12 B_SD11−
AB11 B_SD11+
AC11 B_SD12−
AA11 B_SD12+
AC10 B_SD13−
AB10 B_SD13+
Y11 B_SD14−
AA10 B_SD14+
AC9 B_SD15−
AB9 B_SD15+
Y9 B_SDP0−
AA9 B_SDP0+
AC8 B_SDP1−
AB8 B_SDP1+
Y8 B_SI_O−
AA8 B_SI_O+
AC7 B_SMSG−
AB7 B_SMSG+
AA7 B_SREQ−
AC6 B_SREQ+
AB6 B_SREQ2−
Y6 B_SREQ2+
AA6 B_SRST−
AC5 B_SRST+
AB5 B_SSEL−
Y5 B_SSEL+
F1 C_BE0/
V21 NC
VSS
A_SD7−
AD33
B10
W23 NC
VSS
A_SD7+
AD34
A18
W22 NC
VSS
A_SD8−
AD35
B18
W20 NC
VSS
A_SD8+
AD36
D18
W21 NC
VSS
A_SD9−
AD37
C18
Y23 NC
VSS
A_SD9+
AD38
A19
Y22 NC
VSS
A_SD10−
A_SD10+
A_SD11−
A_SD11+
A_SD12−
A_SD12+
A_SD13−
A_SD13+
A_SD14−
A_SD14+
A_SD15−
A_SD15+
A_SDP0−
A_SDP0+
A_SDP1−
A_SDP1+
A_SI_O−
A_SI_O+
A_SMSG−
A_SMSG+
A_SREQ−
A_SREQ+
A_SREQ2−
A_SREQ2+
A_SRST−
A_SRST+
A_SSEL−
A_SSEL+
ACK64/
AD39
B19
AA23 NC
D22 NC
VSS
AD40
D19
VSS
AD41
C19
D23 NC
VSS
AD42
C4
E21 NC
VSS
AD43
A3
E20 NC
VSS
AD44
B4
E22 NC
VSS
AD45
A4
E23 NC
VSS
AD46
C5
F21 NC
VSS
AD47
D5
F20 PAR
L23 PAR64
L22 PERR/
F22 RBIAS
F23 REQ/
V22 REQ64/
V20 RESERVED
R20 RST/
R21 SCLK
U21 SERR/
V23 STOP/
U23 TCK
U22 TDI
VSS
AD48
B5
AA5
R4
M21
H2
VSS
AD49
A5
VSS
AD50
A10
VSS
AD51
C11
VSS
AD52
C6
AA2
AB14
G1
VSS
AD53
D6
VSS
AD54
B17
VSS
AD55
C17
A21
R3
VSS
AD56
C14
VSS
AD57
A15
R2
VSS
AD58
C16
D1
VSS-A
VSS-CORE
VSS-CORE
VSS-CORE
VSS-CORE
VSS_CORE
AD59
A17
E2
AD60
B16
R23 TDO
R22 TEST_HSC
T23 TMS
T22 TRDY/
V3 TEST_RST/
T2 VDD
E1
Y15
AB19
AC21
F3
AD61
D16
C23
E3
AD62
B14
AD63
D13
P3
C1
ALT_INTA/
B15
D15
AB1
ALT_INTB/
B_DIFFSENS
G3 C_BE1/
D10
U20
Y21 C_BE2/
P1 VDD
6-64
Specifications
Table 6.51 Signal Names By BGA Position
Signal
Name
BGA Signal
Pos Name
BGA Signal
Pos Name
BGA Signal
Pos Name
BGA Signal
Pos Name
BGA
Pos
MAD[4]
MAD[1]
NC
AB20 A_SI_O+
AB21 A_SD9+
AB22 A_SD11+
AB23 VDD-A
AC1 VSS
C17 B_SD3+
C18 B_SD4+
C19 B_SD5−
C20 C_BE3/
C21 AD24
C22 AD26
C23 VDD
D1 VSS
J21
J22
J23
K1
NC
A1
A2
B_SACK2−
DEVSEL/
STOP/
BSERR/
PERR/
B_SMSG−
B_SMSG+
B_SRST+
B_SRST−
PAR
P23
R1
NC
A_SD12+
A_SD13+
A_SD15+
A_SD0+
A_SD2−
A_SD4−
A_SD6−
A_SDP0−
VDD-BIAS2
A_SBSY+
A_SACK2+
A_SACK+
A_SMSG+
A_SC_D+
A_SREQ+
A_SD8−
A_SD10−
A_DIFFSENS
SCLK
A3
R2
NC
A4
R3
R4
NC
NC
K2
A5
AC2 NC
K3
K4
A6
R20
R21
R22
R23
T1
C_BE6/
C_BE4/
AD61
AC3 TEST_HSC
AC4 TCK
AC5 VSS-CORE
AC6 VDD-CORE
AC7 VSS
AC8 A_SD14+
AC9 A_SDP1+
AC10 VDD
AC11 A_SD3−
AC12 A_SD5−
AC13 VDD
AC14 A_SD7−
VSS
AC15 A_SRST+
AC16 VDD
A7
K10
K11
K12
K13
K14
K20
K21
K22
K23
L1
A8
D2 VSS
A9
AD57
D3 VSS
A10
A11
A12
A13
A14
A15
A16
A17
A18
A19
A20
A21
A22
A23
AA1
AA2
AA3
AA4
AA5
AA6
AA7
AA8
AA9
AA10
AA11
AA12
AA13
AD54
D4 VSS
C_BE1/
AD14
AD15
T2
AD50
D5 VSS
T3
AD46
D6 VDD
T4
AD42
D7 B_SD5+
D8 B_SD6+
D9 B_SD7−
D10 AD23
D11 AD22
D12 IDSEL
D13 AD25
D14 VSS
B_SC_D−
B_SC_D+
B_SSEL+
B_SSEL−
AD13
T20
T21
T22
T23
U1
AD40
AD38
AD34
AD32
L2
B_GPIO1_
MASTER/
B_GPIO4
A_GPIO3
MAS0/
L3
AD12
U2
L4
AD11
U3
L10
L11
L12
L13
L14
L20
L21
L22
L23
M1
VDD
U4
AC17 A_SSEL+
AC18 A_SREQ2+
AC19 VDD
D15 VSS
NC
VDD
U20
U21
U22
U23
V1
D16 VSS
NC
B_SREQ−
B_SREQ2+
B_SREQ2−
AD10
MWE/
D17 VSS
AD1
MAD[5]
VSS-CORE
MAD[2]
MAD[0]
NC
AC20 A_SD9−
AC21 A_SD11−
AC22 VSS
D18 VSS
REQ64/
VSS
D19 B_SD6−
D20 B_SD7+
D21 B_SDP0+
D22 B_SDP0−
D23 AD21
E1 AD19
C_BE7/
PAR64
AD60
AD9
C_BE0/
AD8
V2
AC23 NC
V3
B1 B_SD12−
B2 B_SD12+
B3 TDO
V4
NC
NC
AD56
B_SI_O+
B_SD8−
B_SI_O−
B_SREQ+
AD7
V20
V21
V22
V23
W1
W2
W3
W4
W20
W21
W22
W23
Y1
M2
AD53
A_SD13−
A_SD15−
A_SD0−
A_SD1+
A_SD3+
A_SD5+
A_SD7+
A_SATN−
A_SATN+
A_SACK2−
A_SRST−
A_SSEL−
A_SREQ2−
A_SI_O−
A_SD8+
A_SD10+
VSS-A
B4 TDI
B5 TMS
E2 AD20
M3
AD49
E3 VSS
M4
AD45
B6 VDD-CORE
B7 B_SD13+
B8 B_SD13−
B9 B_SD14−
B10 B_SD14+
B11 ALT_INTA/
B12 INTB/
E4 VSS
M10
M11
M12
M13
M14
M20
M21
M22
M23
N1
AD41
E20 VSS
AD37
AD6
E21 VSS
AD33
AD4
E22 VSS
B_GPIO0_
FETCH/
B_GPIO3
A_GPIO2
MAS1/
AD5
E23 VSS
AA14
AA15
AA16
AA17
AA18
AA19
AA20
AA21
AA22
AA23
AB1
B_SD9+
B_SD10−
B_SD9−
B_SD8+
AD3
F1 VSS
F2 RBIAS
F3 VDD-BIAS
F4 B_SATN−
F20 AD17
F21 AD18
F22 AD16
F23 IRDY/
G1 VSS
B13 VSS_CORE
B14 INTA/
B15 B_SD15+
B16 B_SD15−
B17 B_SDP1−
B18 B_SDP1+
B19 RST/
MCE/
MAD[6]
MAD[3]
VSS
AD2
Y2
N2
AD0
Y3
N3
VSS
Y4
N4
NC
AD63
Y5
N10
N11
N12
N13
N14
N20
N21
N22
N23
P1
B_SD11+
ACK64/
NC
AD59
Y6
B20 INT_DIR
B21 ALT_INTB/
B22 VDD
G2 VSS
VDD
Y7
NC
G3 VSS
AB2
AD52
Y8
NC
G4 VSS
NC
AB3
AD48
Y9
NC
B23 VDD
G20 VSS
G21 B_SACK−
G22 B_SBSY+
G23 B_SATN+
H1 B_SBSY−
H2 C_BE2/
H3 FRAME/
H4 TRDY/
H20 VDD
H21 VSS
C_BE5/
AD62
AB4
VDD
Y10
Y11
Y12
Y13
Y14
Y15
TEST_RST/
NC
C1 B_SD0−
C2 B_SD0+
C3 B_SD1−
C4 AD31
AB5
AD44
AD58
AB6
VSS
VSS
AD55
AB7
VDD-CORE
VDD
A_SD12−
A_SD14−
A_SDP1−
A_SD1−
A_SD2+
A_SD4+
A_SD6+
A_SDP0+
A_SBSY−
A_SACK−
A_SMSG−
A_SC_D−
A_SREQ−
AD51
AB8
C5 REQ/
AD47
AB9
VSS-CORE
A_GPIO1_
MASTER/
VDD
C6 CLK
P2
AD43
AB10
AB11
AB12
AB13
AB14
AB15
C7 GNT/
P3
AD39
Y16
Y17
C8 B_SD2−
C9 B_SD1+
C10 B_SD2+
C11 B_SD3-
C12 AD27
P4
AD36
P10
P11
P12
P13
P14
P20
P21
P22
AD35
MOE/_TESTOUT Y18
MAD[7]
VSS
B_DIFFSENS
B_SD11−
B_SD10+
H22 VSS
RESERVED
B_GPIO2
A-GPIO0_
FETCH/
A_GPIO4
VDD-CORE
VSS-CORE
Y19
Y20
Y21
Y22
Y23
H23 VSS
J1 VSS
C13 AD28
J2 VSS
AB16
AB17
AB18
AB19
C14 AD30
J3 VDD
C15 AD29
J4 B_SACK+
J20 B_SACK2+
C16 B_SD4−
SCSI Timing Diagrams
6-65
Figure 6.40 SYM53C896 329 BGA (Bottom View)
6-66
Specifications
CSI
i
a
mas
MD98.BL
Important:
This drawing may not be the latest version. For board layout and manufacturing, obtain
the most recent engineering drawings from your LSI Logic marketing representative by
requesting the outline drawing for package code BL.
-67
6-68
Specifications
Appendix A
Register Summary
Table A.1
SYM53C896 Register Map
Register Name
Address
Read/Write Page
PCI Registers
Vendor ID
0x00–0x01
0x02–0x03
0x04–0x05
0x06–0x07
0x08
Read Only
Read Only
Read/Write
Read/Write
Read Only
Read Only
Read/Write
Read/Write
Read Only
–
4-2
Device ID
4-3
Command
4-3
Status
4-5
Revision ID (Rev ID)
Class Code
4-6
0x09–0x0B
0x0C
4-7
Cache Line Size
4-7
Latency Timer
0x0D
4-8
Header Type
0x0E
4-8
Not Supported
0x0F
4-8
Base Address Register Zero (I/O)
Base Address Register One (MEMORY)
Base Address Register Two (SCRIPTS RAM)
Not Supported
0x10–0x13
0x14–0x1B
0x1C–0x23
0x24–0x27
0x28–0x2B
0x2C–0x2D
0x2E–0x2F
0x30–0x33
Read/Write
Read/Write
Read/Write
–
4-9
4-9
4-10
4-10
4-10
4-11
4-12
4-12
Reserved
–
Subsystem Vendor ID
Subsystem ID
Read Only
Read Only
Read/Write
Expansion ROM Base Address
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
A-1
Table A.1
SYM53C896 Register Map (Cont.)
Register Name
Address
Read/Write Page
Capabilities Pointer
0x34
Read Only
–
4-13
4-13
4-14
4-14
4-15
4-15
4-16
4-16
4-16
4-17
4-18
4-19
Reserved
0x35–0x3B
0x3C
Interrupt Line
Read/Write
Read Only
Read Only
Read Only
Read Only
Read Only
Read Only
Read/Write
Read Only
Read Only
Interrupt Pin
0x3D
Min_Gnt
0x3E
Max_Lat
0x3F
Capability ID
0x40
Next Item Pointer
0x41
Power Management Capabilities (PMC)
Power Management Control/Status (PMCSR)
Bridge Support Extensions (PMCSR_BSE)
Data
0x42–0x43
0x44–0x45
0x46
0x47
SCSI Registers
SCSI Control Zero (SCNTL0)
SCSI Control One (SCNTL1)
SCSI Control Two (SCNTL2)
SCSI Control Three (SCNTL3)
SCSI Chip ID (SCID)
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
0x08
0x09
0x0A
0x0B
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read Only
Read Only
4-22
4-25
4-28
4-30
4-32
4-33
4-38
4-38
4-39
4-40
4-41
4-42
SCSI Transfer (SXFER)
SCSI Destination ID (SDID)
General Purpose (GPREG)
SCSI First Byte Received (SFBR)
SCSI Output Control Latch (SOCL)
SCSI Selector ID (SSID)
SCSI Bus Control Lines (SBCL)
A-2
Register Summary
Table A.1
SYM53C896 Register Map (Cont.)
Register Name
Address
Read/Write Page
DMA Status (DSTAT)
0x0C
0x0D
0x0E
0x0F
0x10–0x13
0x14
Read Only
Read Only
Read Only
Read Only
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read Only
4-42
4-45
4-47
4-49
4-51
4-51
4-55
4-56
4-56
4-57
4-57
4-58
SCSI Status Zero (SSTAT0)
SCSI Status One (SSTAT1)
SCSI Status Two (SSTAT2)
Data Structure Address (DSA)
Interrupt Status Zero (ISTAT0)
Interrupt Status One (ISTAT1)
Mailbox Zero (MBOX0)
0x15
0x16
Mailbox One (MBOX1)
0x17
Chip Test Zero (CTEST0)
Chip Test One (CTEST1)
Chip Test Two (CTEST2)
0x18
0x19
0x1A
Read Only
(bit 3 write)
Chip Test Three (CTEST3)
Temporary (TEMP)
0x1B
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read Only
4-60
4-61
4-61
4-62
4-64
4-66
4-66
4-67
4-67
4-67
4-68
4-68
4-68
0x1C–0x1F
0x20
DMA FIFO (DFIFO)
Chip Test Four (CTEST4)
Chip Test Five (CTEST5)
Chip Test Six (CTEST6)
DMA Byte Counter (DBC)
DMA Command (DCMD)
DMA Next Address (DNAD)
DMA SCRIPTS Pointer (DSP)
DMA SCRIPTS Pointer Save (DSPS)
Scratch Register A (SCRATCHA)
DMA Mode (DMODE)
0x21
0x22
0x23
0x24–0x26
0x27
0x28–0x2B
0x2C–0x2F
0x30–0x33
0x34–0x37
0x38
A-3
Table A.1
SYM53C896 Register Map (Cont.)
Register Name
Address
Read/Write Page
DMA Interrupt Enable (DIEN)
Scratch Byte Register (SBR)
DMA Control (DCNTL)
0x39
Read/Write
Read/Write
Read/Write
Read Only
Read/Write
Read/Write
Read Only
Read Only
Read/Write
Read/Write
Read Only
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read Only
Read/Write
Read/Write
Read/Write
Read Only
Read Only
–
4-71
4-72
4-72
4-75
4-75
4-77
4-79
4-81
4-82
4-84
4-84
4-85
4-86
4-88
4-91
4-91
4-92
4-93
4-94
4-96
4-98
4-99
4-100
4-100
4-100
0x3A
0x3B
Adder Sum Output (ADDER)
SCSI Interrupt Enable Zero (SIEN0)
SCSI Interrupt Enable One (SIEN1)
SCSI Interrupt Status Zero (SIST0)
SCSI Interrupt Status One (SIST1)
SCSI Longitudinal Parity (SLPAR)
SCSI Wide Residue (SWIDE)
Chip Type (CTYPE)
0x3C–0x3F
0x40
0x41
0x42
0x43
0x44
0x45
0x46
General Purpose Pin Control (GPCNTL)
SCSI Timer Zero (STIME0)
SCSI Timer One (STIME1)
Response ID Zero (RESPID0)
Response ID One (RESPID1)
SCSI Test Zero (STEST0)
SCSI Test One (STEST1)
0x47
0x48
0x49
0x4A
0x4B
0x4C
0x4D
0x4E
SCSI Test Two (STEST2)
SCSI Test Three (STEST3)
SCSI Input Data Latch (SIDL)
SCSI Test Four (STEST4)
0x4F
0x50–0x51
0x52
Reserved
0x53
SCSI Output Data Latch (SODL)
Chip Control 0 (CCNTL0)
0x54–0x55
0x56
Read/Write
Read/Write
A-4
Register Summary
Table A.1
SYM53C896 Register Map (Cont.)
Register Name
Address
Read/Write Page
Chip Control 1 (CCNTL1)
0x57
Read/Write
Read Only
–
4-102
4-104
4-104
4-104
4-105
4-106
4-107
4-107
4-107
4-108
4-108
4-108
4-108
4-109
4-109
4-110
4-110
4-111
4-111
4-111
4-112
4-112
4-112
SCSI Bus Data Lines (SBDL)
Reserved
0x58–0x59
0x5A–0x5B
0x5C–0x5F
0x60–0x9F
0xA0–0xA3
0xA4–0xA7
0xA8–0xAB
0xAC–0xAF
0xB0–0xB3
0xB4–0xB7
0xB8–0xBB
0xBC–0xBF
0xC0–0xC3
0xC4–0xC7
0xC8–0xCB
0xCC–0xCF
0xD0–0xD3
0xD4–0xD7
0xD8–0xDA
0xDB
Scratch Register B (SCRATCHB)
Scratch Registers C–R (SCRATCHC–SCRATCHR)
Memory Move Read Selector (MMRS)
Memory Move Write Selector (MMWS)
SCRIPTS Fetch Selector (SFS)
DSA Relative Selector (DRS)
Static Block Move Selector (SBMS)
Dynamic Block Move Selector (DBMS)
DMA Next Address 64 (DNAD64)
Reserved
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
–
Phase Mismatch Jump Address 1 (PMJAD1)
Phase Mismatch Jump Address 2 (PMJAD2)
Remaining Byte Count (RBC)
Updated Address (UA)
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read Only
–
Entry Storage Address (ESA)
Instruction Address (IA)
SCSI Byte Count (SBC)
Reserved
Cumulative SCSI Byte Count (CSBC)
Reserved
0xDC–0xDF
0xE0–0xFF
Read/Write
–
A-5
A-6
Register Summary
Appendix B
External Memory
Interface Diagram
Examples
Figure B.1 16 Kbyte Interface with 200 ns Memory
MOE/
MCE/
OE
CE
D[7:0]
MAD[7:0]
Bus
A[7:0]
V
DD
A[13:8]
MAD0
4.7 K
27C128
D[7:0]
8
SYM53C896
8
6
Q[7:0]
QE
HCT374
CK
MAS0/
MAS1/
Q[5:0]
QE
D[5:0]
HCT374
CK
6
Note: MAD[3:1] pulled low internally. MAD bus sense logic enabled for 16 Kbyte of slow memory (200 ns devices
@ 33 MHz).
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
B-1
Figure B.2 64 Kbyte Interface with 150 ns Memory
Optional - for Flash Memory only, not
required for EEPROMS.
VPP
+ 12 V
VPP
GPIO4
Control
MWE/
WE
OE
CE
MOE/
MCE/
D[7:0]
A[7:0]
MAD[7:0]
Bus
V
DD
27C512-15/
28F512-15/
A[15:8]
MAD2 4.7 K
Socket
SYM53C896
D[7:0]
8
8
6
Q[7:0]
QE
HCT374
CK
MAS0/
MAS1/
Q[5:0]
D[5:0]
HCT374
CK
6
QE
Note: MAD 3, 1, 0 pulled low internally. MAD bus sense logic enabled for 64 Kbyte of fast memory (150 ns devices
@ 33 MHz).
B-2
External Memory Interface Diagram Examples
Figure B.3 128, 256, 512 Kbyte or 1 Mbyte Interface with 150 ns Memory
Optional - for Flash Memory only, not
required for EEPROMS.
VPP
+ 12 V
VPP
GPIO4
Control
MWE/
MOE/
WE
OE
CE
MCE/
D[7:0]
MAD[7:0]
Bus
A[7:0]
V
DD
27C020-15/
28F020-15/
Socket
A[15:8]
MAD3 4.7 K
A[19:16]
SYM53C896
D[7:0]
8
8
6
Q[7:0]
QE
HCT374
CK
MAS0/
MAS1/
Q[5:0]
D[5:0]
HCT374
CK
6
QE
MAD[3:0]
Bus
Q[3:0]
QE
4
D[3:0]
4
HCT374
CK
E
Note: MAD[2:0] pulled low internally. MAD bus sense logic enabled for 128, 256, 512 Kbytes, or 1 Mbyte of fast
memory (150 ns devices @ 33 MHz). The HCT374s may be replaced with HCT377s.
B-3
Figure B.4 512 Kbyte Interface with 150 ns Memory
Optional - for Flash Memory only, not
required for EEPROMS.
27C010-15/28F010-15 Sockets
VPP
+ 12 V
VPP
GPIO4
Control
MWE/
WE
WE
WE
WE
MOE/
OE
OE
OE
OE
D[7:0]
D[7:0]
D[7:0]
D[7:0]
D[7:0]
MAD[7:0]
Bus
A[7:0]
V
DD
A0
.
.
A0
.
.
A0
.
.
A0
.
.
MAD3 4.7 K
MAD1 4.7 K
A[15:8]
.
.
.
.
MAD3 4.7 K
SYM53C896
D[7:0]
8
8
8
Q[7:0]
QE
HCT374
CK
MAS0/
A16
CE
A16
CE
A16
CE
A16
CE
Q[7:0]
D[7:0]
8
HCT374
MAS1/
MCE/
CK
QE
MAD[2:0]
Bus
Q0
Q2
D[2:0]
3
Y0
Y1
Y2
Y3
HCT374
CK
E
A
B
GB
HCT139
Note: MAD[2] pulled low internally. MAD bus sense logic enabled for 512 Kbytes of slow memory (150 ns devices,
additional time required for HCT139 @ 33 MHz). The HCT374s may be replaced with HCT377s.
B-4
External Memory Interface Diagram Examples
Index
(CTEST3) 4-60
(CTEST4) 4-62
(CTEST5) 4-64
(CTEST6) 4-66
(CTYPE) 4-84
(D1S) 4-17
Symbols
(64TIMOD) 4-103
(A7) 5-24
(AAP) 4-24
(ABRT) 4-43, 4-51
(ACK) 4-40, 4-42
(ADB) 4-25
(ADCK) 4-64
(ADDER) 4-75
(AESP) 4-26
(AIP) 4-46
(ARB[1:0]) 4-22
(ART) 4-92
(ATN) 4-40, 4-42
(AUXC) 4-17
(AWS) 4-95
(BARO) 4-9
(BART) 4-10
(BARZ) 4-9
(D2S) 4-17
(DACK) 4-59
(DATA) 4-19
(DBC) 4-66
(DBMS) 4-108
(DCMD) 4-67
(DCNTL) 4-72
(DDAC) 4-102
(DDIR) 4-58, 4-65
(DF[7:0]) 4-66
(DFE) 4-43
(DFIFO) 4-61
(DFS) 4-65
(DHP) 4-26
(DID) 4-3
(DIEN) 4-71
(BBCK) 4-65
(BDIS) 4-62
(BF) 4-43, 4-71
(BL) 4-68
(BL2) 4-65
(BO) 4-61
(DIF) 4-95
(DIFF) 4-50
(DILS) 4-101
(DIOM) 4-70
(DIP) 2-43, 2-46, 2-48, 4-54
(DMODE) 4-68
(DNAD) 4-67
(DNAD64) 4-108
(DPE) 4-5
(DPR) 4-6, 4-102
(DREQ) 4-59
(DRS) 4-107
(DSA) 4-51
(DSCL[1:0]) 4-17
(DSI) 4-17, 4-97
(DSLT[3:0]) 4-18
(DSP) 4-67
(DSPS) 4-68
(DSTAT) 4-42
(DT[1:0]) 4-5
(EBM) 4-4
(BO[9:8]) 4-65
(BOF) 4-70
(BSE) 4-18
(BSY) 4-40, 4-42
(C_D) 4-40, 4-42, 4-49
(CC) 4-7
(CCF[2:0]) 4-31
(CCNTL0) 4-100
(CCNTL1) 4-102
(CHM) 4-28
(CID) 4-16
(CIO) 4-58
(CLF) 2-46, 4-60
(CLS) 4-7
(CLSE) 2-6, 4-72
(CM) 4-58
(CMP) 2-44, 4-76, 4-79
(COM) 4-74
(CON) 4-26, 4-53
(CP) 4-13
(CSBC) 4-112
(CSF) 2-46, 4-98
(CTEST0) 4-57
(CTEST1) 4-57
(CTEST2) 4-58
(EIS) 4-4
(EMS) 4-4
(EN64DBMV) 4-103
(EN64TIBMV) 4-103
(ENC[3:0]) 4-33, 4-38
(ENID) 4-41
(ENNDJ) 4-101
(ENPMJ) 4-100
(EPC) 4-24
Symbios SYM53C896 PCI to Dual Channel Ultra2 SCSI Multifunction Controller
IX-1
(EPER) 4-3
(MPEE) 4-63
(ERBA) 4-12
(ERL) 4-70
(MSG) 4-40, 4-42, 4-49
(NC) 4-6
(ERMP) 4-70
(ESA) 4-111
(EWS) 4-31
(NIP) 4-16
(OLF) 4-45
(OLF1) 4-50
(EXC) 4-25
(ORF) 4-45
(EXT) 4-95
(ORF1) 4-49
(FBL[2:0]) 4-64
(FBL3) 4-63
(FE) 4-85
(PAR) 4-77, 4-81
(PCICIE) 4-58
(PEN) 4-18
(FF[3:0]) 4-47
(FF4) 4-50
(PFEN) 4-73
(PFF) 4-73
(FFL) 4-57
(PMC) 4-16
(FLF) 4-60
(FLSH) 4-55
(FM) 4-60
(PMCSR) 4-17
(PMCSR_BSE) 4-18
(PMEC) 4-17
(FMT) 4-57
(PMES) 4-16
(GEN) 4-78, 4-82
(GEN[3:0]) 4-89
(GENSF) 4-88
(GPCNTL) 4-85
(GPIO) 4-39
(GPIO[1:0]) 4-85
(GPIO[4:2]) 4-85
(GPREG) 4-38
(HSC) 4-97
(PMJAD1) 4-109
(PMJAD2) 4-109
(PMJCTL) 4-101
(PST) 4-17
(PWS[1:0]) 4-18
(QEN) 4-93
(QSEL) 4-94
(RBC) 4-110
(REQ) 4-40, 4-42
(RESPID0) 4-91
(RESPID1) 4-91
(RID) 4-6
(RMA) 4-5
(ROF) 4-95
(RRE) 4-32
(RSL) 4-76, 4-80
(RST) 4-26, 4-46, 4-77, 4-81
(RTA) 4-5
(HT) 4-8
(HTH) 4-78, 4-82
(HTH[3:0]) 4-86
(HTHBA) 4-88
(HTHSF) 4-89
(I/O) 4-9, 4-40, 4-42, 4-49
(IA) 4-111
(IARB) 4-27
(IID) 4-44, 4-71
(IL) 4-14
(S16) 4-97
(ILF) 4-45
(SBC) 4-111
(ILF1) 4-49
(SBCL) 4-42
(INTF) 4-53
(IP) 4-14
(SBDL) 4-104
(SBMC) 4-77, 4-82
(SBMS) 4-108
(SBR) 4-72
(SCE) 4-94
(SCF[2:0]) 4-31
(SCID) 4-32
(IRM[1:0]) 4-94
(IRQD) 4-74
(IRQM) 4-74
(ISO) 4-93
(ISTAT0) 4-51
(ISTAT1) 4-55
(LDSC) 4-50
(LEDC) 4-85
(LOA) 4-46
(LOCK) 4-99
(LOW) 4-96
(LT) 4-8
(M/A) 4-75, 4-79
(MAN) 4-71
(SCLK) 4-93
(SCNTL0) 4-22
(SCNTL1) 4-25
(SCNTL2) 4-28
(SCNTL3) 4-30
(SCRATCHA) 4-68
(SCRATCHB) 4-104
(SCRATCHC–SCRATCHR) 4-105
(SCRIPTS RAM) 4-10
(SDID) 4-38
(MASR) 4-65
(MBOX0) 4-56
(MBOX1) 4-56
(MDPE) 4-43, 4-71
(ME) 4-85
(SDP0) 4-46
(SDP0L) 4-49
(SDP1) 4-51
(SDU) 4-28
(MEMORY) 4-9
(MG) 4-15
(ML) 4-15
(SE) 4-3
(SEL) 4-40, 4-42, 4-76, 4-79
(SEM) 4-52
(MMRS) 4-106
(MMWS) 4-107
(MO[4:0]) 4-36
(SFBR) 4-39
(SFS) 4-107
(SGE) 4-76, 4-80
IX-2
Index
(SI) 4-55
(SID) 4-12
(SIEN0) 4-75
(SIEN1) 4-77
(SIGP) 4-52, 4-58
(SIP) 4-54
(WRIE) 4-61
(WSR) 4-30
(WSS) 4-29
(ZMOD) 4-102
(ZSD) 4-63
(SIR) 4-43, 4-71
(SIST0) 4-79
(SIST1) 4-81
(SLB) 4-95
(SLPAR) 4-82
(SLPHBEN) 4-29
(SLPMD) 4-29
(SLT) 4-92
(SMODE[1:0]) 4-99
(SOCL) 4-40
(SODL) 4-100
(SOM) 4-93
Numerics
16-bit system (S16) 4-97
32/64-bit jump 5-31
32-bit addressing 5-6
3-State 3-3
64 Kbytes ROM read cycle 6-56, 6-57
64-bit
addressing 5-7
addressing in SCRIPTS 2-20
SCRIPT selectors 4-106
table indirect indexing mode (64TIMOD) 4-103
8-bit/16-bit SCSI 2-35
(SOZ) 4-92
(SPL1) 4-50
(SRE) 4-32
A
(SRST) 4-52
(SRTM) 4-63
(SRUN) 4-55
(SSAID) 4-92
(SSE) 4-5
(SSI) 4-43, 4-71
(SSID) 4-41
(SSM) 4-73
A and B DIFFSENS SCSI signals 6-3
A[6:0] 5-23
A_DIFFSENS 3-14
A_GPIO0_ FETCH/ 3-11
A_GPIO1_ MASTER/ 3-11
A_GPIO2 3-11
A_GPIO3 3-11
A_GPIO4 3-11
A_SACK+- 3-15
A_SACK2+- 3-15
A_SATN+- 3-15
A_SBSY+- 3-15
A_SC_D+- 3-15
A_SCTRL signals 3-15
A_SD[15:0]+- 3-14
A_SDP[1:0]+- 3-14
A_SI_O+- 3-15
A_SMSG+- 3-15
A_SREQ+- 3-15
(SST) 4-27
(SSTAT0) 4-45
(SSTAT1) 4-47
(SSTAT2) 4-49
(START) 4-23
(STD) 4-74
(STEST0) 4-92
(STEST1) 4-93
(STEST2) 4-94
(STEST3) 4-96
(STEST4) 4-99
(STIME0) 4-86
(STIME1) 4-88
(STO) 4-78, 4-82
(STR) 4-97
A_SREQ2+- 3-15
A_SRST+- 3-15
A_SSEL+- 3-15
(STW) 4-98
aborted (ABRT) 4-43, 4-51, 4-71
absolute maximum stress ratings 6-1
AC characteristics 6-11
ACK64/ 3-7
acknowledge 64 3-7
active negation
see TolerANT technology
active termination 2-37
AD[63:0] 3-6
adder sum output (ADDER) 4-75
address and data signals 3-6
address/data bus 2-3
alt interrupt
A 3-10
B 3-10
ALT_INTA/ 3-10
ALT_INTB/ 3-10
always wide SCSI (AWS) 4-95
arbitration
(SWIDE) 4-84
(SXFER) 4-33
(SZM) 4-95
(TE) 4-96
(TEMP) 4-61
(TEOP) 4-59
(TP[2:0]) 4-33
(TRG) 4-24
(TTM) 4-98
(TYP) 4-84
(UA) 4-110
(UDC) 4-77, 4-80
(USE) 4-30
(V) 4-60
(VAL) 4-41
(VER[2:0]) 4-17
(VUE0) 4-29
(VUE1) 4-30
(WATN) 4-24
(WIE) 4-4
in progress (AIP) 4-46
mode bits 1 and 0 (ARB[1:0]) 4-22
priority encoder test (ART) 4-92
(WOA) 4-46
Index
IX-3
signals 3-8
assert
64-bits address and data 6-32
burst write
even SCSI parity (force bad parity) (AESP) 4-26
SATN/ on parity error (AAP) 4-24
SCSI
32-bits address and data 6-34
64-bits address and data 6-36
bus
ACK/ signal (ACK) 4-40, 4-42
ATN/ signal (ATN) 4-40, 4-42
BSY/ signal (BSY) 4-40, 4-42
C_D/ signal (C_D) 4-40, 4-42
data bus (ADB) 4-25
command and byte enables 3-6
fault (BF) 4-43, 4-71
byte
count 5-39
empty in DMA FIFO (FMT) 4-57
full in DMA FIFO (FFL) 4-57
offset counter (BO) 4-61
I_O/ signal (I/O) 4-40, 4-42
MSG/ signal (MSG) 4-40, 4-42
REQ/ signal (REQ) 4-40, 4-42
RST/ signal (RST) 4-26
SEL/ signal (SEL) 4-40, 4-42
asynchronous SCSI
receive 2-31
send 2-29
Aux_Current 4-17
C
C_BE[3:0]/ 2-3
C_BE[7:0]/ 3-6
cache line size
(CLS) 2-7, 4-7
enable (CLSE) 2-7, 4-72
register 2-6, 2-10
cache mode, see PCI cache mode 2-10
call instruction 5-28
B
B_DIFFSENS 3-17
B_GPIO0_FETCH/ 3-12
B_GPIO1_MASTER/ 3-12
B_GPIO2 3-12
Cap_ID (CID) 4-16
capabilities pointer (CP) 4-13
capability ID register 4-16
carry test 5-31
B_GPIO3 3-12
B_GPIO4 3-12
B_SACK+- 3-18
B_SACK2+- 3-18
chained block moves 2-51
SCRIPTS instruction 2-52
SODL register 2-52
B_SATN+- 3-18
B_SBSY+- 3-18
B_SC_D+- 3-18
B_SD[15:0]+- 3-16
B_SDP[1:0]+- 3-16
B_SI_O+- 3-18
SWIDE register 2-52
wide SCSI receive bit 2-51
wide SCSI send bit 2-51
chained mode (CHM) 4-28
change bus phases 2-18
chip
B_SMSG+- 3-18
B_SREQ+- 3-18
B_SREQ2+- 3-18
B_SRST+- 3-18
control 0 (CCNTL0) 4-100
control 1 (CCNTL1) 4-102
revision level (V) 4-60
test five (CTEST5) 2-7, 4-64
test four (CTEST4) 2-26, 4-62
test one (CTEST1) 4-57
test six (CTEST6) 4-66
test three (CTEST3) 2-8, 2-11, 4-60
test two (CTEST2) 4-58
test zero (CTEST0) 4-57
type (CTYPE) 4-84
B_SSEL+- 3-18
back-to-back read
32-bits address and data 6-26
back-to-back write
32-bits address and data 6-28
base address register
one (BARO) 2-3, 4-9
two (BART) 4-10
type (TYP) 4-84
zero (BARZ) 2-3, 4-9
bidirectional 3-3
signals 6-4, 6-5
BIOS 2-3
bits used for parity control and generation 2-26
block move 2-9
CHMOV 2-51
class code register 4-7
clear DMA FIFO (CLF) 2-46, 4-60
clear instruction 5-17, 5-18
clear SCSI FIFO (CSF) 2-46, 4-98
CLK 3-5
instructions 5-4
clock 3-5
bridge support extensions (BSE) 4-18
burst
address incrementor (ADCK) 4-64
byte counter (BBCK) 4-65
conversion factor (CCF[2:0]) 4-31
quadrupler 2-22
disable (BDIS) 4-62
length (BL) 4-68
length bit 2 (BL2) 4-65
opcode fetch
command register 4-3
compare
32-bits address and data 6-24
opcode fetch enable (BOF) 4-70
size selection 2-7
data 5-32
phase 5-32
configuration
burst read
read command 2-5
32-bits address and data 6-30
space 2-3
IX-4
Index
write command 2-6
configured
size (DFS) 4-65
interrupt 2-44, 2-45, 2-46
as I/O (CIO) 4-58
as memory (CM) 4-58
enable (DIEN) 2-26, 2-43, 2-45, 4-71
interrupt pending (DIP) 4-54
interrupts 2-46
mode (DMODE) 2-6, 2-7, 2-8, 2-11, 2-23, 4-68
next address (DNAD) 4-67
next address 64 (DNAD64) 4-108
SCRIPTS
connected (CON) 4-26, 4-53
cumulative SCSI byte count (CSBC) 4-112
current
function of input voltage 6-9
function of output voltage 6-10
cycle frame 3-7
pointer (DSP) 4-67
pointer save (DSPS) 4-68
status (DSTAT) 2-26, 2-42, 2-43, 2-46, 2-47, 2-48, 4-42
DSA
D
relative 5-38
relative selector (DRS) 4-107
DSPS register 5-36
dual address cycles 2-20
dynamic block move selector (DBMS) 4-108
D1_Support (D1S) 4-17
D2_Support (D2S) 4-17
data
(DATA) 4-19
acknowledge status (DACK) 4-59
compare mask 5-32
compare value 5-33
parity error reported (DPR) 4-6
paths 2-29
E
enable
request status (DREQ) 4-59
structure address (DSA) 4-51
transfer direction (DDIR) 4-58
data_scale (DSCL[1:0]) 4-17
data_select (DSLT[3:0]) 4-18
data-in 2-52, 2-53
64-bit
direct BMOV (EN64DBMV) 4-103
table indirect BMOV (EN64TIBMV) 4-103
bus mastering (EBM) 4-4
I/O space (EIS) 4-4
jump on nondata phase mismatches (ENNDJ) 4-101
memory space (EMS) 4-4
parity
data-out 2-52, 2-53
DC characteristics 6-1
decode of MAD pins 3-24
default download mode 2-57
destination
checking 2-25
checking (EPC) 4-24
error response (EPER) 4-3
phase mismatch jump (ENPMJ) 4-100
read
line (ERL) 4-70
multiple (ERMP) 4-70
response to
address 5-24
I/O-memory enable (DIOM) 4-70
detected parity error (from slave) (DPE) 4-5
determining data transfer rate 2-39
device
ID (DID) 4-3
select 3-8
specific initialization (DSI) 4-17
DEVSEL/ 3-8
reselection (RRE) 4-32
selection (SRE) 4-32
wide SCSI (EWS) 4-31
enabling cache mode 2-10
encoded
timing (DT[1:0]) 4-5
diffsens mismatch (DIFF) 4-50
DIP 2-46
chip SCSI ID (ENC[3:0]) 4-33
destination SCSI ID
direct 5-20
(ENC[3:0]) 4-38
disable
(ENID) 4-41
auto FIFO clear (DISFC) 4-101
dual address cycle (DDAC) 4-102
halt on parity error or ATN (target only) (DHP) 4-26
internal load/store (DILS) 4-101
pipe req (DPR) 4-102
single initiator response (DSI) 4-97
disconnect 2-18
SCSI destination ID 5-21
entry storage address (ESA) 4-111
error reporting signals 3-9
even parity 2-25
expansion ROM base address 2-55, 2-56, 4-12
extend SREQ/SACK filtering (EXT) 4-95
external
disconnect instruction 5-16
DMA
clock 6-11
memory interface 2-55
configuration 2-56
byte counter (DBC) 4-66
command (DCMD) 4-67
control (DCNTL) 2-6, 2-7, 2-8, 2-44, 4-72
direction (DDIR) 4-65
FIFO 2-8, 2-28, 2-43
(DF[7:0]) 4-66
diagram examples B-1
multiple byte accesses 6-13
slow memory 2-56
memory read 6-38
memory timing 6-38
(DFIFO) 4-61
memory write 6-41
byte offset counter, bits [9:8] (BO[9:8]) 4-65
empty (DFE) 4-43
extra clock cycle of data setup (EXC) 4-25
sections 2-29
Index
IX-5
write command 2-5
IDSEL 2-3, 3-8
F
signal 2-6
fetch
illegal instruction detected (IID) 4-44, 4-71
immediate
enable (FE) 4-85
pin mode (FM) 4-60
FIFO
arbitration (IARB) 4-27
data 5-24
indirect addressing 5-5
initialization device select 3-8
initiator
byte control (FBL[2:0]) 4-64
byte control (FBL3) 4-63
flags (FF[3:0]) 4-47
flags, bit 4 (FF4) 4-50
asynchronous receive 6-58
asynchronous send 6-58
mode 5-11, 5-17
phase mismatch 4-79
ready 3-7
first dword 5-5, 5-15, 5-23, 5-27, 5-38
flush DMA FIFO (FLF) 4-60
flushing (FLSH) 4-55
FRAME/ 3-7
frequency lock (LOCK) 4-99
full arbitration, selection/reselection 4-23
function complete 2-44
synchronous transfer 6-63
timing 6-22
input 3-3
(CMP) 4-76, 4-79
capacitance 6-3
current as a function of input voltage 6-9
signals 6-5
G
instruction
general description 1-1
general purpose
address (IA) 4-111
prefetch unit flushing 2-22
type 5-38
(GPREG) 4-38
I/O (GPIO) 4-39
I/O pin 0 3-11, 3-12
I/O pin 1 3-11, 3-12
I/O pin 2 3-11, 3-12
I/O pin 3 3-11, 3-12
I/O pin 4 3-11, 3-12
block move 5-5
I/O instruction 5-15
memory move 5-35
read/write instruction 5-23
transfer control instruction 5-27
INT_DIR 3-10
INTA routing enable 3-23
INTA, INTB disable (IRQD) 4-74
INTA/ 2-42, 2-45, 2-48, 3-10, 3-23
INTB/ 2-42, 2-45, 2-48, 3-10, 3-23
interface
pin control (GPCNTL) 4-85
timer expired (GEN) 2-44, 4-78, 4-82
timer period (GEN[3:0]) 4-89
timer scale factor (GENSF) 4-88
GNT/ 2-10, 3-8
GPIO enable (GPIO[1:0]) 4-85
GPIO enable (GPIO[4:2]) 4-85
grant 3-8
128, 256, 512 Kbyte or 1 Mbyte
150 ns memory B-3
16 Kbyte
200 ns memory B-1
512 Kbyte
150 ns memory B-4
64 Kbyte
H
halt SCSI clock (HSC) 4-97
halting 2-47
handshake-to-handshake
timer bus activity enable (HTHBA) 4-88
timer expired (HTH) 2-44, 4-78, 4-82
timer period (HTH[3:0]) 4-86
timer scale factor (HTHSF) 4-89
hardware control of SCSI activity LED 2-20
hardware interrupts 2-41
150 ns memory B-2
control signals 3-7
internal
arbiter 2-10
SCRIPTS RAM 2-19
internal RAM
see also SCRIPTS RAM 2-19
interrupt
header type (HT) 4-8
A 3-10
high impedance mode (ZMOD) 4-102
high voltage differential interface 2-35
high voltage differential mode
autoswitching with LVD and single-ended mode 2-33
description 2-33
acknowledge command 2-5
B 3-10
direction 3-10
handling 2-41
instruction 5-29
HVD or SE/LVD (DIF) 4-95
HVD signals 2-34
line 4-14
on-the-fly (IN) 5-31
on-the-fly (INTF) 4-53
output 6-12
I
pin (IP) 4-14
I/O 3-3
request 2-42
instructions 5-15
read command 2-5
space 2-3
routing mode (IRM[1:0]) 4-94
signals 3-10
status one (ISTAT1) 2-42, 4-55
IX-6
Index
status zero (ISTAT0) 2-42, 4-51
interrupt-on-the-fly instruction 5-29
interrupts 2-44
MAS1/ 3-19
masking 2-45
master
fatal vs. nonfatal interrupts 2-44
halting 2-47
masking 2-45
control for set or reset pulses (MASR) 4-65
data parity error (MDPE) 4-43, 4-71
enable (ME) 4-85
sample interrupt service routine 2-47
stacked interrupts 2-46
IRDY/ 3-7
parity error enable (MPEE) 4-63
max SCSI synchronous offset (MO[4:0]) 4-36
Max_Lat (ML) 4-15
IRQ mode (IRQM) 4-74
issuing cache commands 2-11
maximum stress ratings 6-1
MCE/ 3-19
memory
address strobe 0 3-19
address strobe 1 3-19
address/data bus 3-19
chip enable 3-19
I/O address/DSA offset 5-39
move 2-9
move instructions 2-23, 5-34
no flush option 2-23
move read selector (MMRS) 4-106
move write selector (MMWS) 4-107
output enable 3-19, 3-20
read 2-11
J
JTAG boundary scan testing 2-24
jump
address 5-33
call a relative address 5-30
call an absolute address 5-30
control (PMJCTL) 4-101
if true/false 5-31
instruction 5-27
JUMP64 address 5-33
read caching 2-11
read command 2-5
L
read line 2-10, 2-12
last disconnect (LDSC) 4-50
latched SCSI parity
(SDP0L) 4-49
for SD[15:8] (SPL1) 4-50
latency 2-9
read line command 2-7
read multiple 2-10, 2-12
read multiple command 2-6
space 2-3
to memory 2-17
to memory moves 2-17
write 2-11, 2-12
write and invalidate 2-10
write and invalidate command 2-8
write caching 2-12
write command 2-5
write enable 3-19
timer (LT) 4-8
LED_CNTL (LEDC) 4-85
load and store instructions
prefetch unit and store instructions 2-23
load/store 5-39
load/store instructions 2-24, 5-37
loopback enable 2-25
lost arbitration (LOA) 4-46
low voltage differential See LVD Link 2-33
LVD
Min_Gnt (MG) 4-15
MOE/_TESTOUT 3-19, 3-20
move to/from SFBR cycles 5-24
multiple cache line transfers 2-9
MWE/ 3-19
driver SCSI signals 6-2
receiver SCSI signals 6-3
SCSI 1-4
LVD Link 1-1, 1-4
N
benefits 1-4
operation 2-33
new capabilities (NC) 4-6
new features in the SYM53C896 1-3
next item pointer register 4-16
Next_Item_Ptr (NIP) 4-16
no download mode 2-58
no flush 5-35
M
MAD
bus 2-56
bus programming 3-23
pins 2-56
store instruction only 5-39
nonburst opcode fetch
MAD[0] 3-24
MAD[3:1] 3-23
MAD[4] 3-23
MAD[5] 3-23
MAD[6] 3-23
MAD[7:0] 3-19, 3-23
MAD[7] 3-23
32-bits address and data 6-22
normal/fast memory ( 128 Kbytes)
multiple byte access read cycle 6-48
multiple byte access write cycle 6-50
single byte access read cycle 6-44
single byte access write cycle 6-46
mailbox one (MBOX1) 2-42, 4-56
mailbox zero (MBOX0) 2-42, 4-56
manual start mode (MAN) 4-71
MAS0/ 3-19
O
opcode 5-10, 5-15, 5-23, 5-27
fetch burst capability 2-23
Index
IX-7
operating conditions 6-2
operating register/SCRIPTS RAM read
32-bits 6-17
state D1 2-59
state D2 2-60
state D3 2-60
64-bits 6-18
prefetch
operating register/SCRIPTS RAM write
32-bits 6-19
enable (PFEN) 4-73
flush 2-23
64-bits 6-20
flush (PFF) 4-73
operator 5-23
output
SCRIPTS instructions 2-22
pull-ups, internal, conditions 3-4
current as a function of output voltage 6-10
output signals 6-4, 6-6
R
P
RAM, see also SCRIPTS RAM 2-19
RBIAS 3-22
PAR 3-6
read
PAR64 3-7
line 2-10, 2-11
parallel ROM interface 2-55
parallel ROM support 2-56
parity 2-27, 3-6
line function 2-7
modify-write cycles 5-24
multiple 2-8, 2-10, 2-11
multiple with read line enabled 2-8
write instructions 5-23
write system memory from SCRIPTS 5-35
read/write
error 3-9
(PAR) 4-81
options 2-25
parity64 3-7
PCI
instructions 5-23, 5-25
system memory from SCRIPTS 5-35
received
master abort (from master) (RMA) 4-5
target abort (from master) (RTA) 4-5
register
addressing 2-3
bus commands and encoding types 2-4
bus commands and functions supported 2-4
cache line size register 2-8
cache mode 2-10
command register 2-8
commands 2-4
address 5-39
address - A[6:0] 5-23
register map A-1
registers 2-42
relative 5-20
relative addressing mode 5-19, 5-30
remaining byte count (RBC) 4-110
REQ/ 2-10, 3-8
REQ/ - GNT/ 2-2
REQ64/ 3-7
configuration info enable (PCICIE) 4-58
configuration register read 6-15
configuration register write 6-16
configuration registers 4-1
configuration space 2-3
external memory interface timing diagrams 6-13
functional description 2-2
I/O space 2-3
interface signals 3-5
master transaction 2-11
master transfer 2-11
memory space 2-3
request 3-8
request 64 3-7
reselect 2-18
during reselection 2-38
instruction 5-15
performance 1-7
target disconnect 2-9
target retry 2-9
PERR/ 3-9
reselected (RSL) 2-44, 4-76, 4-80
reserved command 2-5
reset 3-5
phase mismatch
input 6-12
handling in SCRIPTS 2-19
jump address 1 (PMJAD1) 4-109
jump address 2 (PMJAD2) 4-109
jump registers 4-109
physical dword address and data 3-6
PME
SCSI offset (ROF) 4-95
response ID one (RESPID1) 4-91
response ID zero (RESPID0) 4-91
return instruction 5-28
revision ID register 4-6
(RID) 4-6
clock (PMEC) 4-17
enable (PEN) 4-18
rise and fall time test condition 6-8
ROM
status (PST) 4-17
support (PMES) 4-16
polling 2-41
flash and memory interface signals 3-19
interface 2-55
pin 2-56
power
RST/ 3-5
and ground signals 3-21
management 2-58
S
capabilities 4-16
control/status 4-17
state (PWS[1:0]) 4-18
state D0 2-59
SACK 2-47
SACs 2-20
SCLK 3-13
IX-8
Index
quadrupler enable (QEN) 4-93
quadrupler select (QSEL) 4-94
scratch
loopback mode (SLB) 2-25, 4-95
low level mode (LOW) 4-96
LVD Link 2-33
byte register (SBR) 4-72
register A (SCRATCHA) 4-68
register B (SCRATCHB) 4-104
registers C–R (SCRATCHC–SCRATCHR) 4-105
script fetch selector (SFS) 4-107
SCRIPTS
mode (SMODE[1:0]) 4-99
MSG/ signal (MSG) 4-49
output control latch (SOCL) 4-40
output data latch (SODL) 2-51, 2-52, 2-53, 4-100
parity control 2-27
parity error (PAR) 4-77
instruction 2-51
interrupt instruction received (SIR) 4-43, 4-71
processor 2-18
parity errors and interrupts 2-27
performance 1-6
phase 5-12, 5-29
internal RAM for instruction storage 2-19
performance 2-18
phase mismatch - initiator mode 4-75
registers 4-20
RAM 2-4, 2-19
running (SRUN) 4-55
SCSI
reset condition (RST) 4-77
RST/ received (RST) 4-81
RST/ signal (RST) 4-46
ATN condition - target mode (M/A) 4-75
bit mode change (SBMC) 4-82
bus control lines (SBCL) 4-42
bus data lines (SBDL) 4-104
bus interface 2-32, 2-39
bus mode change (SBMC) 4-77
byte count (SBC) 4-111
C_D/ signal (C_D) 4-49
SCRIPTS operation 5-1
sample instruction 5-3
SDP0/ parity signal (SDP0) 4-46
SDP1/ parity signal (SDP1) 4-51
selected as ID (SSAID) 4-92
selector ID (SSID) 4-41
serial EEPROM access 2-57
status one (SSTAT1) 2-26, 4-47
status two (SSTAT2) 2-26, 4-49
status zero (SSTAT0) 2-26, 4-45
synchronous offset maximum (SOM) 4-93
synchronous offset zero (SOZ) 4-92
synchronous transfer period (TP[2:0]) 4-33
termination 2-37
test four (STEST4) 4-99
test one (STEST1) 4-93
test three (STEST3) 4-96
test two (STEST2) 2-25, 4-94
test zero (STEST0) 4-92
timer one (STIME1) 4-88
timer zero (STIME0) 4-86
timing diagrams 6-58
TolerANT technology 1-5
transfer (SXFER) 2-40, 4-33
true end of process 4-59
Ultra2 SCSI 2-21
chip ID (SCID) 4-32
clock (SCLK) 3-13, 4-93
control enable (SCE) 4-94
control one (SCNTL1) 2-26, 4-25
control three (SCNTL3) 2-39, 2-40, 4-30
control two (SCNTL2) 2-51, 4-28
control zero (SCNTL0) 2-26, 4-22
cumulative byte count 4-112
data high impedance (ZSD) 4-63
destination ID (SDID) 4-38
disconnect unexpected (SDU) 4-28
encoded destination ID 5-21
FIFO test read (STR) 4-97
FIFO test write (STW) 4-98
first byte received (SFBR) 4-39
function A control 3-15
function A GPIO signals 3-11
function A signals 3-13
function B control 3-18
valid (VAL) 4-41
function B GPIO signals 3-12
function B signals 3-16
functional description 2-18
gross error (SGE) 4-76, 4-80
hysteresis of receivers 6-9
I_O/ signal (I/O) 4-49
wide residue (SWIDE) 2-52, 4-84
SCSI high impedance mode (SZM) 4-95
SCSI-1
transfers
(differential 4.17 Mbytes) 6-60
(single-ended 5.0 Mbytes) 6-60
SCSI-2
input data latch (SIDL) 4-98
input filtering 6-8
fast transfers
instructions
10.0 Mbytes (8-bit transfers)
40 MHz Clock 6-61
block move 5-4
I/O 5-15
50 MHz Clock 6-61
read/write 5-23
interface signals 3-13
20.0 Mbytes (16-bit transfers)
40 MHz Clock 6-61
interrupt enable one (SIEN1) 2-43, 4-77
interrupt enable zero (SIEN0) 2-26, 2-43, 4-75
interrupt pending (SIP) 4-54
interrupt status one (SIST1) 2-42, 2-43, 2-46, 2-47, 4-81
interrupt status zero (SIST0) 2-26, 2-42, 2-43, 2-46, 2-47, 4-
79
50 MHz Clock 6-61
second dword 5-14, 5-22, 5-24, 5-33, 5-36, 5-39
select 2-18
during selection 2-38
instruction 5-17
with ATN/ 5-21
interrupts 2-46
isolation mode (ISO) 4-93
longitudinal parity (SLPAR) 4-82
with SATN/ on a start sequence (WATN) 4-24
selected (SEL) 2-44, 4-76, 4-79
selection or reselection time-out (STO) 4-78, 4-82
Index
IX-9
selection response logic test (SLT) 4-92
semaphore (SEM) 4-52
serial EEPROM
SYM53C896
329 ball grid array 6-66
329 BGA mechanical drawing 6-67
new features 1-3
data format 2-58
interface 2-57
register map A-1
SERR/ 3-9
SYNC_IRQD (SI) 4-55
synchronous
SERR/ enable (SE) 4-3
set instruction 5-16, 5-18
set/clear
clock conversion factor (SCF[2:0]) 4-31
data transfer rates 2-39
operation 2-39
carry 5-21
SACK/ 5-21
SCSI receive 2-31
SATN/ 5-22
SCSI send 2-30
target mode 5-21
system error 3-9
shadow register test mode (SRTM) 4-63
SIDL
system signals 3-5
least significant byte full (ILF) 4-45
most significant byte full (ILF1) 4-49
signal names
and BGA position 6-64
by BGA position 6-64
signal process (SIGP) 4-52, 4-58
signaled system error (SSE) 4-5
simple arbitration 4-22
single
address cycles 2-20
ended SCSI signals 6-7
step interrupt (SSI) 4-43, 4-71
step mode (SSM) 4-73
SIP 2-43, 2-46
slow memory ( 128 Kbytes)
read cycle 6-52
write cycle 6-54
slow ROM pin 3-24
SLPAR high byte enable (SLPHBEN) 4-29
SLPAR mode (SLPMD) 4-29
SODL
T
table indirect 5-6, 5-20
mode 5-19
table relative 5-20
target
asynchronous receive 6-59
asynchronous send 6-59
mode 5-10, 5-15
SATN/ active (M/A) 4-79
mode (TRG) 4-24
ready 3-7
synchronous transfer 6-63
timing 6-15
TCK 3-20
TDI 3-20
TDO 3-20
TEMP register 5-37
temporary (TEMP) 4-61
termination 2-37
test clock 3-20
least significant byte full (OLF) 4-45
most significant byte full (OLF1) 4-50
register 2-52
test data in 3-20
test data out 3-20
test halt SCSI clock 3-20
test interface signals 3-20
test mode select 3-20
test reset 3-20
TEST_HSC 3-20
TEST_RSTN 3-20
third dword 5-14, 5-33, 5-36
timer test mode (TTM) 4-98
TMS 3-20
SODR
least significant byte full (ORF) 4-45
most significant byte full (ORF1) 4-49
software reset (SRST) 4-52
source
I/O-memory enable (SIOM) 4-69
special cycle command 2-5
SREQ 2-47
stacked interrupts 2-46
start
TolerANT 1-5
enable (TE) 4-96
technology 1-5
address 5-14, 5-22
DMA operation (STD) 4-74
SCSI transfer (SST) 4-27
sequence (START) 4-23
static block move selector (SBMS) 4-108
status register 4-5
STOP command 2-9
stop signal 3-8
STOP/ 3-8
store instruction 2-23
stress ratings 6-1
subsystem ID 2-58
(SID) 4-12
subsystem vendor ID 2-58
(SVID) 4-11
benefits 1-5
electrical characteristics 6-7
Totem Pole Output 3-3
transfer
control 2-23
control instructions 5-27
and SCRIPTS instruction prefetching 2-23
count 5-35
counter 5-13
information 2-18
rate synchronous 2-39
TRDY/ 2-9, 3-7
U
SWIDE register 2-52
SYM53C700 compatibility (COM) 4-74
ultra SCSI
IX-10
Index
clock conversion factor bits 4-32
enable (USE) 4-30
high voltage differential transfers
20.0 Mbytes (8-bit transfers)
80 MHz clock 6-62
40.0 Mbytes (16-bit transfers)
80 MHz clock 6-62
single-ended transfers
20.0 Mbytes (8-bit transfers)
quadrupled 40 MHz clock 6-62
40.0 Mbytes (16-bit transfers)
quadrupled 40 MHz clock 6-62
Ultra2 SCSI 1-4
benefits 1-4
designing an Ultra2 SCSI system 2-21
LVD Link 2-33
synchronous data transfers 2-40
transfers
40.0 Mbytes (8-bit transfers)
quadrupled 40 MHz clock 6-63
80.0 Mbytes (16-bit transfers)
quadrupled 40 MHz clock 6-63
unexpected disconnect (UDC) 4-77, 4-80
updated address (UA) 4-110
upper register address line (A7) 5-24
use data8/SFBR 5-23
V
VDD 3-21
-A 3-21
-Bias 3-21
-Bias2 3-21
-Core 3-21
vendor
ID (VID) 4-2
unique enhancement, bit 1 (VUE1) 4-30
unique enhancements, bit 0 (VUE0) 4-29
version (VER[2:0]) 4-17
VSS 3-21
-A 3-21
-Core 3-21
W
wait
disconnect instruction 5-18
for disconnect 2-18
for valid phase 5-32
reselect instruction 5-18
select instruction 5-16
wide SCSI
chained block moves 2-51
receive (WSR) 4-30
receive bit 2-51
send (WSS) 4-29
send bit 2-51
won arbitration (WOA) 4-46
write
read instructions 5-23
read system memory from SCRIPTS 5-35
write and invalidate 2-9, 2-10, 2-11
enable (WIE) 4-4
enable (WRIE) 4-61
WSR bit 2-52
WSS flag 2-51
Index
IX-11
IX-12
Index
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Date
Telephone
Title
Fax
Department
Company Name
Street
Mail Stop
City, State, Zip
Customer Feedback
U.S. Distributors
by State
A. E.
Avnet Electronics
Colorado
Denver
Indiana
Fort Wayne
I. E.
W. E. Tel: 888.358.9953
Indianapolis
A. E.
Minnesota
Champlin
http://www.hh.avnet.com
B. M.
Bell Microproducts,
Inc. (for HAB’s)
A. E.
B. M.
Tel: 303.790.1662
Tel: 303.846.3065
Tel: 219.436.4250
B. M.
Tel: 800.557.2566
Eden Prairie
http://www.bellmicro.com
I. E.
http://www.insight-electronics.com
W. E. Wyle Electronics
http://www.wyle.com
W. E. Tel: 800.933.9953
Englewood
B. M.
Tel: 800.255.1469
Insight Electronics
Tel: 317.575.3500
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I. E.
Tel: 303.649.1800
A. E.
Tel: 612.346.3000
Iowa
W. E. Tel: 800.860.9953
St. Louis Park
Connecticut
Cheshire
W. E. Tel: 612.853.2280
Cedar Rapids
A. E.
I. E.
Tel: 612.525.9999
Alabama
Daphne
I. E.
Huntsville
A. E.
I. E.
A. E.
I. E.
Tel: 203.271.5700
Tel: 203.272.5843
Tel: 319.393.0033
Mississippi
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Kansas
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Kansas City
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A. E.
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W. E. Tel: 256.830.1119
Tel: 256.837.8700
Tel: 256.830.1222
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Missouri
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North/South
Lenexa
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St. Louis
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Tel: 800.638.5988
Tel: 302.328.8968
Tel: 913.492.0408
Alaska
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I. E.
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Tel: 314.872.2182
A. E.
Tel: 800.332.8638
Kentucky
W. E. Tel: 937.436.9953
Central/Northern/ Western
B. M.
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Montana
Florida
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A. E.
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Tel: 800.767.0329
Tel: 800.829.0146
A. E.
Tel: 800.526.1741
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Arizona
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I. E.
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Tel: 407.834.6310
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Tel: 602.267.9551
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I. E.
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W. E. Tel: 800.528.4040
Tempe
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Nevada
Las Vegas
A. E.
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Tel: 800.231.5575
I. E.
Tel: 727.524.8850
I. E.
Tel: 480.829.1800
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A. E.
A. E.
Tel: 800.528.8471
A. E.
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Tel: 407.657.3300
W. E. Tel: 407.740.7450
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North/South
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Tel: 949.470.2900
Tel: 949.727.3291
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W. E. Tel: 800.626.9953
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Tel: 800.673.7461
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Tel: 818.594.0404
Georgia
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A. E.
Massachusetts
Boston
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Wayne
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Tel: 781.270.9400
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Tel: 858.597.3010
Tel: 800.677.6011
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Tel: 800.851.2282
Tel: 801.365.3800
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Hawaii
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Tel: 781.933.9010
A. E.
Tel: 505.293.5119
Idaho
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B. M.
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Tel: 408.435.3500
Tel: 408.436.0881
Tel: 408.952.7000
Michigan
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Tel: 810.229.7710
Santa Clara
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Woodland Hills
Illinois
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Tel: 734.416.5800
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A. E.
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Schaumburg
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U.S. Distributors
by State
(Continued)
New York
South Carolina
Wisconsin
Hauppauge
A. E.
Tel: 919.872.0712
Milwaukee
I. E.
Tel: 516.761.0960
W. E. Tel: 919.469.1502
A. E.
Tel: 414.513.1500
Long Island
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Wauwatosa
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Tel: 800.829.0116
W. E. Tel: 800.861.9953
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Tel: 414.258.5338
W. E. Tel: 612.853.2280
Wyoming
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I. E.
Tel: 716.475.9130
Tel: 716.242.7790
Tennessee
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Tel: 800.332.9326
W. E. Tel: 801.974.9953
W. E. Tel: 800.319.9953
Smithtown
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Tel: 800.241.8182
Tel: 800.633.2918
B. M.
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Texas
Austin
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B. M.
I. E.
North Carolina
Raleigh
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Tel: 512.219.3700
Tel: 512.258.0725
Tel: 512.719.3090
Tel: 919.859.9159
Tel: 919.873.9922
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A. E.
B. M.
Tel: 214.553.4300
Tel: 972.783.4191
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Tel: 800.829.0116
W. E. Tel: 800.955.9953
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W. E. Tel: 612.853.2280
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Tel: 800.526.9238
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Tel: 713.917.0663
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W. E. Tel: 800.763.9953
Dayton
B. M.
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I. E.
Tel: 614.888.3313
Tel: 937.253.7501
I. E.
Tel: 972.783.0800
W. E. Tel: 800.575.9953
Strongsville
Rio Grande Valley
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Tel: 210.412.2047
B. M.
Valley View
Tel: 440.238.0404
Stafford
I. E.
Tel: 281.277.8200
I. E.
Tel: 216.520.4333
Utah
Oklahoma
Centerville
W. E. Tel: 972.235.9953
Tulsa
B. M.
Murray
I. E.
Tel: 801.295.3900
A. E.
I. E.
Tel: 918.459.6000
Tel: 918.665.4664
Tel: 801.288.9001
Salt Lake City
A. E.
Tel: 801.365.3800
Oregon
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W. E. Tel: 800.477.9953
B. M.
I. E.
Tel: 503.524.0787
Tel: 503.644.3300
Vermont
A. E.
Tel: 800.272.9255
Portland
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W. E. Tel: 716.334.5970
Tel: 503.526.6200
Virginia
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Tel: 800.638.5988
Pennsylvania
W. E. Tel: 301.604.8488
Mercer
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W. E. Tel: 440.248.9996
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A. E.
B. M.
Washington
Kirkland
Tel: 412.662.2707
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Tel: 425.820.8100
Tel: 412.281.4150
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Tel: 800.526.4812
Tel: 215.741.4080
West Virginia
W. E. Tel: 800.871.9953
A. E.
Tel: 800.638.5988
Rhode Island
A. E.
800.272.9255
W. E. Tel: 781.271.9953
Direct Sales
Representatives by State
(Component and HAB)
E. A.
E. L.
GRP
I. S.
ION
R. A.
Earle Associates
Electrodyne - UT
Group 2000
Infinity Sales, Inc.
ION Associates, Inc.
Rathsburg Associ-
ates, Inc.
Texas
Austin
ION
Arlington
ION
Tel: 512.794.9006
Tel: 817.695.8000
Tel: 281.376.2000
Houston
ION
SGY
Synergy Associates,
Inc.
Utah
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Arizona
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E. A.
E. L.
Tel: 801.264.8050
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Tel: 480.921.3305
R. A.
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Tel: 414.679.8250
California
Calabasas
Tel: 414.268.1152
I. S.
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I. S.
Tel: 818.880.6480
Tel: 714.833.0300
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Tel: 619.278.5441
Illinois
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R. A.
Tel: 630.516.8400
Indiana
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R. A.
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R. A.
Tel: 317.984.8608
Tel: 219.894.3184
Tel: 317.838.0360
Plainfield
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Massachusetts
Burlington
SGY
Tel: 781.238.0870
Michigan
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R. A.
Tel: 616.554.1460
Good Rich
R. A.
Novi
R. A.
Tel: 810.636.6060
Tel: 810.615.4000
North Carolina
Cary
GRP
Tel: 919.481.1530
Ohio
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R. A.
Tel: 614.457.2242
Dayton
R. A.
Tel: 513.291.4001
Independence
R. A.
Tel: 216.447.8825
Pennsylvania
Somerset
R. A.
Tel: 814.445.6976
Sales Offices and Design
Resource Centers
LSI Logic Corporation
Corporate Headquarters
Tel: 408.433.8000
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Tel: 301.897.5800
Fax: 301.897.8389
INTERNATIONAL
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Taipei
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Taiwan Branch
Tel: 886.2.2718.7828
Fax: 886.2.2718.8869
France
Paris
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Immeuble Europa
♦ Tel: 33.1.34.63.13.13
Fax: 33.1.34.63.13.19
Fax: 408.433.8989
NORTH AMERICA
Massachusetts
Waltham
California
♦ Tel: 781.890.0180
United Kingdom
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LSI Logic Europe Ltd
♦ Tel: 44.1344.426544
Fax: 44.1344.481039
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Fax: 949.752.6868
Fax: 781.890.6158
Germany
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LSI Logic GmbH
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Fax: 49.89.4.58.33.108
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♦ Sales Offices with
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International Distributors
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Reptechnic Pty Ltd
♦ Tel: 612.9953.9844
Fax: 612.9953.9683
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Fax: 81.3.3260.7100
Technical Center
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Belgium
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Tel: 32.2.7205983
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China
Beijing
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Services Inc.
Tel: 86.10.6804.2534
Fax: 86.10.6804.2521
The Netherlands
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Acal Nederland b.v.
Tel: 31.40.2.502602
Fax: 31.40.2.510255
France
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Tel: 33.1.41806310
Fax: 33.1.41730340
Switzerland
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LSI Logic Sulzer AG
Tel: 41.32.3743232
Fax: 41.32.3743233
Germany
Haar
EBV Elektronik
Tel: 49.89.4600980
Fax: 49.89.46009840
Taiwan
Taipei
Avnet-Mercuries
Corporation, Ltd
Tel: 886.2.2516.7303
Fax: 886.2.2505.7391
Munich
Avnet Emg GmbH
Tel: 49.89.45110102
Fax: 49.89.42.27.75
Lumax International
Corporation, Ltd
Wuennenberg-Haaren
Peacock AG
Tel: 886.2.2788.3656
Fax: 886.2.2788.3568
Tel: 49.2957.79.1692
Fax: 49.2957.79.9341
Prospect Technology
Corporation, Ltd
Hong Kong
Hong Kong
Tel: 886.2.2721.9533
Fax: 886.2.2773.3756
AVT Industrial Ltd
Tel: 852.2428.0008
Fax: 852.2401.2105
Serial Semiconductor
Corporation, Ltd
Tel: 886.2.2579.5858
Fax: 886.2.2570.3123
EastEle
Tel: 852.2798.8860
Fax: 852.2305.0640
United Kingdom
Maidenhead
India
Bangalore
Spike Technologies India
Private Ltd
Azzurri Technology Ltd
Tel: 44.1628.826826
Fax: 44.1628.829730
♦ Tel: 91.80.664.5530
Swindon
Fax: 91.80.664.9748
EBV Elektronik
Tel: 44.1793.849933
Fax: 44.1793.859555
Israel
Tel Aviv
Eastronics Ltd
Tel: 972.3.6458777
Fax: 972.3.6458666
♦ Sales Offices with
Design Resource Centers
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SYN100E137JCTR
100E SERIES, ASYN POSITIVE EDGE TRIGGERED 8-BIT UP BINARY COUNTER, PQCC28, PLASTIC, LCC-28
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SYN10E137JCTR
10E SERIES, ASYN POSITIVE EDGE TRIGGERED 8-BIT UP BINARY COUNTER, PQCC28, PLASTIC, LCC-28
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