1、ANSI INCITS 302-1998 (R2003)(formerly ANSI X3.302-1998)for Information Technology SCSI Parallel Interface-2 (SPI-2)ANSIX3.302-1998American National Standardfor Information Technology SCSI Parallel Interface-2 (SPI-2)SecretariatInformation Technology Industry CouncilApproved November 11, 1998 America
2、n National Standards Institute, Inc.AbstractThis standard defines mechanical, electrical, timing requirements, command, and the task managementdelivery protocol requirements to transfer commands and data between SCSI devices attached to an SCSIparallel interface. This standard is intended to be used
3、 in conjunction with the SCSI command sets. Theresulting interface facilitates the interconnection of computers and intelligent peripherals and thus pro-vides a common interface standard for both system integrators and suppliers of intelligent peripherals.Approval of an American National Standard re
4、quires review by ANSI that therequirements for due process, consensus, and other criteria for approval havebeen met by the standards developer.Consensus is established when, in the judgement of the ANSI Board ofStandards Review, substantial agreement has been reached by directly andmaterially affect
5、ed interests. Substantial agreement means much more thana simple majority, but not necessarily unanimity. Consensus requires that allviews and objections be considered, and that a concerted effort be madetowards their resolution.The use of American National Standards is completely voluntary; theirex
6、istence does not in any respect preclude anyone, whether he has approvedthe standards or not, from manufacturing, marketing, purchasing, or usingproducts, processes, or procedures not conforming to the standards.The American National Standards Institute does not develop standards andwill in no circu
7、mstances give an interpretation of any American NationalStandard. Moreover, no person shall have the right or authority to issue aninterpretation of an American National Standard in the name of the AmericanNational Standards Institute. Requests for interpretations should beaddressed to the secretari
8、at or sponsor whose name appears on the titlepage of this standard.CAUTION NOTICE: This American National Standard may be revised orwithdrawn at any time. The procedures of the American National StandardsInstitute require that action be taken periodically to reaffirm, revise, orwithdraw this standar
9、d. Purchasers of American National Standards mayreceive current information on all standards by calling or writing the AmericanNational Standards Institute.American National StandardPublished byAmerican National Standards Institute, Inc.11 West 42nd Street, New York, NY 10036Copyright 1999 by Inform
10、ation Technology Industry Council (ITI)All rights reserved.No part of this publication may be reproduced in anyform, in an electronic retrieval system or otherwise,without prior written permission of ITI, 1250 Eye Street NW, Washington, DC 20005. Printed in the United States of AmericaCAUTION: The d
11、evelopers of this standard have requested that holders of patents that may be re-quired for the implementation of the standard disclose such patents to the publisher. However, nei-ther the developers nor the publisher have undertaken a patent search in order to identify which, ifany, patents may app
12、ly to this standard. As of the date of publication of this standard, followingcalls for the identification of patents that may be required for the implementation of the standard,notice of one or more such claims has been received. By publication of this standard, no positionis taken with respect to
13、the validity of this claim or of any rights in connection therewith. The knownpatent holder(s) has (have), however, filed a statement of willingness to grant a license underthese rights on reasonable and nondiscriminatory terms and conditions to applicants desiring to ob-tain such a license. Details
14、 may be obtained from the publisher. No further patent search is con-ducted by the developer or publisher in respect to any standard it processes. No representation ismade or implied that this is the only license that may be required to avoid infringement in the use ofthis standard.iContentsPageFore
15、word . xiii1 Scope 12 Normative references 32.1 Approved references 32.2 References under development . 42.3 Other references 43 Definitions, symbols, abbreviations, and conventions . 43.1 Definitions 43.2 Symbols and abbreviations 83.3 Keywords . 93.4 Conventions . 93.5 Notation for Procedures and
16、Functions 104 General . 114.1 Overview 114.1.1 Data transfer modes 114.1.2 Cables, Connectors, Signals, Transceivers 114.1.3 Physical architecture of bus 114.1.4 Physical topology details and definitions . 124.1.5 Bus loading . 154.1.6 Termination requirements . 154.1.7 Device Addressing 154.1.8 Pro
17、tocol . 155 SCSI parallel interface connectors 185.1 Nonshielded connector 185.1.1 Nonshielded connector alternative 1 - A cable 185.1.2 Nonshielded connector alternative 2 - A cable 185.1.3 Nonshielded connector alternative 3 - P cable and Q cable . 185.1.4 Nonshielded connector alternative 4 . 195
18、.2 Shielded connector 245.2.1 Shielded connector alternative 1 - A cable 255.2.2 Shielded connector alternative 2 - A cable 255.2.3 Shielded connector alternative 3 - P cable and Q cable . 255.2.4 Shielded connector alternative 4 - P cable and Q cable . 255.3 Connector contact assignments . 345.3.1
19、SE assignments 355.3.2 Differential connector contact assignments 396 SCSI bus interconnect 466.1 SCSI bus cables . 466.2 Interconnect characteristics for signals 476.3 Decoupling characteristics for TERMPWR and TERMPWRQ lines . 496.4 Connection requirements for RESERVED lines . 506.5 Cables used wi
20、th SE transceivers 506.5.1 SE ground offset . 516.6 Cables used with differential transceivers 526.6.1 HVD stub length and spacing 526.6.2 LVD stub length and spacing 53iiPage7 SCSI parallel interface electrical characteristics . 547.1 SE alternative . 557.1.1 SE termination . 557.1.2 SE output char
21、acteristics 567.1.3 SE input characteristics . 587.1.4 SE input and output characteristics . 597.2 LVD alternative . 607.2.1 LVD termination 607.2.2 LVD driver characteristics . 647.2.3 LVD receiver characteristics . 657.2.4 LVD capacitive loads . 667.2.4.1 Management of LVD release glitches 687.2.5
22、 SE/HVD transmission mode detection 697.2.5.1 LVD DIFFSENS driver . 697.2.5.2 LVD DIFFSENS receiver 707.3 LVD/MSE multimode alternative 727.3.1 LVD/MSE multimode termination 727.3.2 LVD/MSE multimode transceiver characteristics 737.3.3 Power for LVD/MSE multimode transceivers 757.3.4 Ground drivers
23、757.4 HVD alternative 757.4.1 HVD termination 757.4.2 HVD output characteristics 777.4.3 HVD input characteristics 787.4.4 SE driver protection . 807.5 Terminator power . 808 SCSI bus signals . 828.1 Signal descriptions . 838.2 Parity checking rules 848.3 Signal states . 858.3.1 SE . 858.3.2 Differe
24、ntial . 858.4 OR-tied signals . 878.5 Signal sources 879 SCSI parallel bus timing 889.1 Timing description 909.1.1 Arbitration delay 909.1.2 Bus clear delay 909.1.3 Bus free delay . 909.1.4 Bus set delay . 909.1.5 Bus settle delay . 909.1.6 Cable skew 909.1.7 Data release delay 909.1.8 Disconnection
25、 delay 909.1.9 Power on to selection 909.1.10 Receive assertion period . 919.1.11 Receive hold time 919.1.12 Receive negation period . 919.1.13 Receive setup time 91iiiPage9.1.14 Receive period tolerance . 919.1.15 Reset hold time . 919.1.16 Reset to Selection . 919.1.17 Selection abort time . 919.1
26、.18 Selection time-out delay 919.1.19 Signal Timing Skew . 929.1.20 System deskew delay 929.1.21 Transmit assertion period 929.1.22 Transmit hold time . 929.1.23 Transmit negation period . 929.1.24 Transmit setup time . 929.1.25 Transmit period tolerance 929.2 Measurement points . 929.2.1 SE fast-10
27、 data transfer rates . 929.2.2 SE fast-20 data transfer rates . 939.2.3 LVD . 949.2.4 HVD . 959.3 Setup and hold timings . 969.3.1 Fast-10 data transfer rates 969.3.2 Fast-20 data transfer rates 989.3.3 Fast-40 data transfer rates 10010 Removal and insertion of SCSI devices 10210.1 Case 1 - Power-of
28、f during removal or insertion 10210.2 Case 2 - RST signal asserted continuously during removal or insertion 10210.3 Case 3 - Current I/O processes not allowed during insertion or removal . 10210.4 Case 4 - Current I/O process allowed during insertion or removal . 10311 Logical characteristics . 1041
29、1.1 SCSI bus phases 10411.1.1 BUS FREE phase 10411.1.1.1 Unexpected bus free 10411.1.2 ARBITRATION phase . 10511.1.3 SELECTION phase . 10611.1.3.1 SELECTION time-out procedure 10611.1.4 RESELECTION phase 10611.1.4.1 RESELECTION 10611.1.4.2 RESELECTION time-out procedure . 10711.1.5 Information trans
30、fer phases . 10711.1.5.1 Asynchronous information transfer . 10811.1.5.2 Synchronous data transfer . 10911.1.5.3 Wide data transfer 11011.1.6 COMMAND phase . 11111.1.7 Data phase 11111.1.7.1 DATA IN phase 11111.1.7.2 DATA OUT phase 11111.1.8 STATUS phase . 11111.1.8.1 STATUS phase exception conditio
31、n handling 11211.1.9 Message phase . 11211.1.9.1 MESSAGE IN phase 11211.1.9.1.1 MESSAGE IN phase exception condition handling . 11211.1.9.2 MESSAGE OUT phase 112ivPage11.1.9.2.1 MESSAGE OUT phase exception condition handling . 11211.1.10 Signal restrictions between phases . 11311.2 SCSI bus conditio
32、ns . 11311.2.1 Attention condition . 11311.2.2 Hard reset . 11411.2.3 Reset events . 11411.2.3.1 Transceiver mode change reset event . 11411.3 SCSI bus phase sequences . 11511.4 SCSI pointers . 11611.5 SCSI Interlocked Protocol messages . 11711.5.1 Message protocols and formats 11711.5.1.1 Message p
33、rotocol rules 11711.5.1.2 Message formats 11711.5.1.2.1 One-byte messages 11811.5.1.2.2 Two-byte messages 11811.5.1.2.3 Extended messages 11811.5.2 Link control messages 11911.5.2.1 CONTINUE TASK 11911.5.2.2 DISCONNECT . 12011.5.2.3 IDENTIFY . 12011.5.2.4 IGNORE WIDE RESIDUE 12111.5.2.5 INITIATOR DE
34、TECTED ERROR . 12211.5.2.6 MESSAGE PARITY ERROR . 12211.5.2.7 MESSAGE REJECT 12311.5.2.8 MODIFY DATA POINTER 12311.5.2.9 NO OPERATION 12311.5.2.10 RESTORE POINTERS 12411.5.2.11 SAVE DATA POINTER 12411.5.2.12 SYNCHRONOUS DATA TRANSFER REQUEST . 12411.5.2.12.1 Target initiated SDTR negotiation . 12611
35、.5.2.12.2 Initiator initiated SDTR negotiation 12711.5.2.13 TARGET TRANSFER DISABLE 12711.5.2.14 TASK COMPLETE . 12811.5.2.15 WIDE DATA TRANSFER REQUEST 12811.5.2.15.1 Target initiated WDTR negotiation 13011.5.2.15.2 Initiator initiated WDTR negotiation . 13111.5.3 Task attribute messages . 13111.5.
36、3.1 ACA 13211.5.3.2 HEAD OF QUEUE . 13211.5.3.3 LINKED COMMAND COMPLETE . 13311.5.3.4 LINKED COMMAND COMPLETE (WITH FLAG) 13311.5.3.5 ORDERED . 13311.5.3.6 SIMPLE 13311.5.4 Task management messages . 13411.5.4.1 ABORT TASK 13411.5.4.2 ABORT TASK SET 13511.5.4.3 CLEAR ACA . 13511.5.4.4 CLEAR TASK SET
37、 . 13511.5.4.5 LOGICAL UNIT RESET . 13511.5.4.6 TARGET RESET 13611.5.4.7 TERMINATE TASK 13611.6 Command processing considerations and exception conditions . 136vPage11.6.1 Asynchronous event notification 13611.6.2 Incorrect initiator connection . 13711.6.3 Unexpected reselection . 13711.7 Use of dis
38、connect-reconnect page parameters 13711.8 SCSI parallel interface services . 13911.8.1 Procedure terms 13911.8.2 Application client SCSI command services . 14111.8.2.1 Send SCSI command service 14111.8.3 Device server SCSI command services 14111.8.3.1 Data-in delivery service 14111.8.3.2 Data-out de
39、livery service 14211.8.4 Task management services 14211.8.4.1 Task management function service 14211.8.4.1.1 ABORT TASK 14211.8.4.1.2 ABORT TASK SET 14211.8.4.1.3 CLEAR ACA 14311.8.4.1.4 CLEAR TASK SET 14311.8.4.1.5 LOGICAL UNIT RESET 14311.8.4.1.6 RESET SERVICE DELIVERY SUBSYSTEM 14311.8.4.1.7 TARG
40、ET RESET . 14311.8.4.1.8 TERMINATE TASK . 14311.8.4.1.9 WAKEUP . 143AnnexesA Additional requirements for LVD SCSI drivers and receivers . 144A.1 System level requirements . 144A.2 Driver requirements . 144A.2.1 Differential output voltage, VS 145A.2.2 Offset (common-mode output) voltage, VCM 147A.2.
41、3 Short-circuit currents, IO-S and IO+S . 148A.2.4 Open-circuit output voltages, VO-(OC)and VO+(OC) . 149A.2.5 Output signal waveform 150A.2.6 Dynamic output signal balance, VCM(PP) 151A.3 Receiver characteristics . 153A.3.1 Receiver steady state input voltage requirements 153A.3.2 Compliance test 1
42、53A.3.3 Receiver setup and hold times 154A.4 Transceiver characteristics 154A.4.1 Transceiver output/input currents, II-L and II+L 155A.4.2 Transceiver maximum input voltages 155B SCSI configured automatically (SCAM) 156B.1 Model . 156B.2 Glossary . 156B.3 SCAM requirements . 156B.3.1 Configuration
43、requirements . 156B.3.2 Timing requirements . 157B.3.2.1 SCAM tolerant power-on to selection delay . 157B.3.2.2 SCAM tolerant reset to selection delay 157B.3.2.3 SCAM tolerant selection response time . 158B.3.2.4 SCAM unassigned ID selection response delay 158viPageB.3.2.5 SCAM power-on to SCAM sele
44、ction delay 158B.3.2.6 SCAM reset to SCAM selection delay . 158B.3.2.7 SCAM selection response time 158B.3.2.8 Recommended SCAM selection response time 158B.3.2.9 Wide arbitration time 158B.3.3 Device requirements . 158B.3.3.1 SCAM tolerant target . 159B.3.3.2 Level 1 SCAM initiator . 159B.3.3.3 Lev
45、el 1 SCAM target 159B.3.3.4 Level 2 SCAM initiator . 160B.3.3.5 Level 2 SCAM target 160B.4 SCAM protocol . 161B.4.1 Initiation 161B.4.1.1 Transfer cycles 162B.4.1.2 Wired-OR glitch filtering . 163B.4.1.3 Isolation stage 163B.4.1.4 Function sequences . 167B.4.1.4.1 Isolate function 167B.4.1.4.2 Isola
46、te and set priority flag function 168B.4.1.4.3 Configuration process complete function 169B.4.1.4.4 Dominant initiator contention function . 169B.5 SCAM operations . 169B.5.1 SCAM initiator . 169B.5.1.1 Dominant SCAM initiator . 170B.5.1.1.1 SCSI ID categorization . 170B.5.1.1.2 SCSI ID assignment .
47、 170B.5.1.2 Subordinate SCAM initiator . 171B.5.2 Level 1 SCAM target . 171B.5.3 Level 2 SCAM target . 173C SCSI bus fairness . 175C.1 Model . 175C.2 Determining fairness by monitoring prior bus activity 175C.3 Fairness algorithm . 175C.4 Additional comments . 177D SCA-2 Connector pinouts . 178D.1 S
48、CA-2 Signal Definitions . 178D.1.1 VOLTAGE and GROUND signals 178D.1.2 CHARGE signals 179D.1.3 SPINDLE SYNC . 179D.1.4 ACTIVE LED OUT 180D.1.5 Motor Start Controls . 180D.1.6 SCSI ID Selection . 181D.1.7 MATED Signals 182D.1.7.1 MATED 2/Drive Side . 183D.1.7.2 MATED 2/Backplane Side . 183D.1.7.3 MAT
49、ED 1/Drive Side . 183D.1.7.4 MATED 1/Backplane Side . 183E Interconnecting buses of different widths . 185F Cabling and cable measurement method recommendations 188viiPageF.1 Cabling . 188F.2 Cable measurement . 188F.2.1 Impedance, TDR, single-ended 188F.2.2 Impedance, TDR, differential 188F.2.3 Attenuation, differential . 189F.2.4 Velocity (propagation delay) and skew . 189F.2.5 D.C. resistance 189G Transmission line considerations for fast-20 data transfer rates 190H Measuring SE pin capacitance . 193I SCSI ICONS . 194J Example of HVD terminator network . 196K SCSI-3 to SCSI-2 terminolo
