1、American National StandardDeveloped byfor Information Technology USB Attached SCSI (UAS)INCITS 471-2010INCITS 471-2010Reaffirmed as INCITS 471-2010 R2015INCITS 471-2010American National Standardfor Information Technology USB Attached SCSI (UAS)SecretariatInformation Technology Industry CouncilApprov
2、ed December 7, 2010 American National Standards Institute, Inc.AbstractThis standard specifies the requirements for the USB Attached SCSI (UAS) transport protocol. The UAS transport protocol defines a mechanism to transport SCSI commands using USB hardware. The UAS transport protocol coordinates wit
3、h other members of the SCSI family of standards via the SAM-4 architecture model. This standard is intended to be used in conjunction with SCSI command set standards and USB specifications.Approval of an American National Standard requires review by ANSI that therequirements for due process, consens
4、us, 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 affected interests. Substantial agreement means much more thana simple ma
5、jority, 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; theirexistence does not in any respect preclude anyone, whether he has app
6、rovedthe 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 circumstances give an interpretation of any American NationalStandard. M
7、oreover, 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 secretariat or sponsor whose name appears on the titlepage of this standard.
8、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 standard. Purchasers of American National Standards mayreceive current inf
9、ormation on all standards by calling or writing the AmericanNational Standards Institute.American National StandardPublished byAmerican National Standards Institute, Inc.25 West 43rd Street, New York, NY 10036Copyright 2010 by Information Technology Industry Council (ITI)All rights reserved.No part
10、of this publication may be reproduced in anyform, in an electronic retrieval system or otherwise,without prior written permission of ITI, 1101 K Street NW, Suite 610 Washington, DC 20005. Printed in the United States of AmericaCAUTION: The developers of this standard have requested that holders of p
11、atents 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 apply to this standard. As of the date of publication of this
12、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 the validity of this claim or of any rights in connection t
13、herewith. 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 may be obtained from the publisher. No further patent sear
14、ch 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.iContentsPageForewordvIntroduction.ix1 Scope 12 Normative references .22.1 N
15、ormative references .22.2 Approved references 22.3 References under development .22.4 Other references .33 Definitions, symbols, abbreviations, and conventions .43.1 Definitions .43.2 Symbols and abbreviations 53.3 Keywords 53.4 Editorial conventions 63.5 Numeric and character conventions .73.5.1 Nu
16、meric conventions .73.5.2 Byte encoded character strings conventions 73.6 Sequence figure notation 83.7 Notation for procedures and functions 84 Model .94.1 Overview .94.2 Tag handling .104.3 Data transfers .104.4 UAS domain .114.5 Addressing 124.6 World wide name 124.7 Resets 134.8 I_T Nexus loss 1
17、34.9 Target power loss expected .134.10 USB error handling .135 USB 145.1 Overview .145.2 USB resource requirements .145.2.1 Overview .145.2.2 USB class specific requests 145.2.3 USB descriptors 146 Transport 196.1 Overview .196.2 IUs 196.2.1 Overview .196.2.2 COMMAND IU .206.2.3 READ READY IU 216.2
18、.4 WRITE READY IU .216.2.5 SENSE IU .226.2.6 RESPONSE IU 226.2.7 TASK MANAGEMENT IU .236.3 Information unit sequences 266.3.1 Overview .26ii6.3.2 Non-data command/sense sequence .276.3.3 Non-data command/response sequence 276.3.4 Data-out command sequence .286.3.5 Data-in command sequence .296.3.6 T
19、ask management function sequence 306.3.7 Bi-directional command sequence 316.3.8 Multiple command example 326.4 Transport requirements 347 SCSI Application Layer Transport Protocol Services .357.1 SCSI transport protocol services overview .357.2 Send SCSI Command transport protocol service .367.3 SC
20、SI Command Received transport protocol service 377.4 Send Command Complete transport protocol service 377.5 Command Complete Received transport protocol service .397.6 Send Data-In transport protocol service .397.7 Data-In Delivered transport protocol service 407.8 Receive Data-Out transport protoco
21、l service 407.9 Data-Out Received transport protocol service 417.10 Terminate Data Transfer transport protocol service .417.11 Data Transfer Terminated transport protocol service .427.12 Send Task Management Request transport protocol service .427.13 Task Management Request Received transport protoc
22、ol service 437.14 Task Management Function Executed transport protocol service 447.15 Received Task Management Function Executed transport protocol service 457.16 USB Acknowledgement 468 Device server error handling 47iiiTablesPage1 Standards bodies 22 Numbering conventions 73 Device descriptor 144
23、Configuration descriptor 155 Interface Descriptor. 166 Bulk-in endpoint descriptor. 167 Bulk-out endpoint descriptor. 178 Pipe Usage Descriptor 179 Pipe ID 1810 IU ID field summary 1911 IU Header 1912 COMMAND IU 2013 TASK ATTRIBUTE field 2014 READ READY IU 2115 WRITE READY IU 2116 SENSE IU. 2217 RES
24、PONSE IU. 2218 RESPONSE CODE field. 2319 TASK MANAGEMENT IU. 2420 task management function field 2521 Execute Command procedure call transport protocol services. 3522 Execute Command procedure call transport protocol services. 3623 Send SCSI Command transport protocol service arguments. 3624 SCSI Co
25、mmand Received transport protocol service arguments. 3725 Send Command Complete transport protocol service arguments 3826 Command Complete Received transport protocol service arguments 3927 Send Data-In transport protocol service arguments. 4028 Data-In Delivered transport protocol service arguments
26、. 4029 Receive Data-Out transport protocol service arguments 4130 Data-Out Received transport protocol service arguments 4131 Terminate Data Transfer transport protocol service arguments 4232 Data Transfer Terminated transport protocol service arguments 4233 Send Task Management Request transport pr
27、otocol service arguments. 4234 Task Management Request Received transport protocol service arguments. 4335 Task Management Function Executed transport protocol service arguments 4436 Received Task Management Function Executed transport protocol service arguments 4537 USB Acknowledgement 4638 Deliver
28、y Result to additional sense code mapping. 47ivFiguresPage1 SCSI document relationships 12 Example Sequence figure. 83 USB Model 94 Example Simple UAS domain. 115 Example Complex UAS Domain. 126 UAS sequence figure notation 267 Non-data transfer with Sense. 278 Non-data Transfer with Response 279 Wr
29、ite Data Transfer. 2810 Read Data Transfer 2911 Task Management 3012 Bi-directional Data Transfer 3113 Multiple Command Example. 33vForeword (This foreword is not part of American National Standard INCITS 471-2010.)The purpose of this standard is to define requirements for the transmission of SCSIco
30、mmands, in a manner compliant with SAM-4, across a USB physical interface.Requests for interpretation, suggestions for improvement and addenda, or defect reports are welcome. They should be sent to the INCITS Secretariat, National Committee for Information Technology Standards, Information Technolog
31、y Institute, 1101 K Street, NW, Suite 610, Washington, DC 20005. This standard was processed and approved for submittal to ANSI by the InterNational Committee for Information Technology Standards (INCITS). Committee approval of the standard does not necessarily imply that all committee members voted
32、 for approval. At the time of it approved this standard, INCITS had the following members:Don Wright, ChairJennifer Garner, SecretaryOrganization Represented Name of RepresentativeAdobe Systems Inc.Scott Foshee Steve Zilles (Alt.)AIM Global Inc. Dan Mullen Charles Biss (Alt.)Apple Computer, Inc. .Kw
33、ok Lau Helene Workman (Alt.)David Singer (Alt.)Distributed Management Task Force John Crandall Jeff Hilland (Alt.)Electronic Industries Alliance .Edward Mikoski, Jr. Henry Cuschieri (Alt.)EMC Corporation .Gary Robinson Farance Inc.Frank Farance Timothy Schoechle (Alt.)GoogleZaheda Bhorat GS1 US .Ray
34、 Delnicki Frank Sharkey (Alt.)James Chronowski (Alt.)Mary Wilson (Alt.)Hewlett-Packard Company Karen Higginbottom Paul Jeran (Alt.)IBM Corporation Gerald Lane Robert Weir (Alt.)Arnaud Le Hors (Alt.)Debra Boland (Alt.)Steve Holbrook (Alt.)IEEE.Bill Ash Jodie Haasz (Alt.)Bob Labelle (Alt.)Intel Philip
35、 Wennblom Grace Wei (Alt.)Stephen Balogh (Alt.)Lexmark International.Don Wright Dwight Lewis (Alt.)Paul Menard (Alt.)Jerry Thrasher (Alt.)Microsoft Corporation.Jim Hughes Dick Brackney (Alt.)John Calhoun (Alt.)viOrganization Represented Name of RepresentativeNational Institute of Standards b) compli
36、es with SCSI Architecture Model - 4 (e.g., autosense and command queuing); andc) other capabilities.Device-type specific command sets (e.g., SBC-3 (ISO/IEC 14776-323),SSC-3 (ISO/IEC 14776-333),MMC-5 (ISO/IEC 14776-365)Primary command set(shared for all device types)(SPC-4 (ISO/IEC 14776-454)SCSI tra
37、nsport protocols (e.g., SAS-2 (ISO/IEC 14776-152),FCP-4 (ISO/IEC 14776-224),this standard)Interconnects (e.g.,USB-2, USB-3,SPI-5 (ISO/IEC 14776-115),Fibre Channel (ISO/IEC 14165)SCSIArchitectureModel(SAM-4 (ISO/IEC 14776-414)INCITS 471-201022 Normative references2.1 Normative referencesReferenced st
38、andards and specifications contain provisions that, by reference in the text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate t
39、he possibility of applying the most recent editions of the standards listed below.Copies of the following documents may be obtained from ANSI:a) approved ANSI standards;b) approved and draft international and regional standards (e.g., ISO, IEC); andc) approved and draft foreign standards (e.g., JIS
40、and DIN).For further information, contact ANSI Customer Service Department at 212-642-4900 (phone), 212-302-1286 (fax) or via the World Wide Web at http:/www.ansi.org.Additional availability contact information is provided below as needed.Table1 shows standards bodies and their web sites.2.2 Approve
41、d referencesAt the time of publication, the following referenced standards or technical reports were approved:ISO/IEC 14776-414, SCSI Architecture Model-4 (SAM-4) (ANSI INCITS 447-2008)2.3 References under developmentAt the time of publication, the following referenced standards were still under dev
42、elopment. For information on the current status of the document, or regarding availability, contact the relevant standards body or other organization as indicated.ISO/IEC 14776-454, SCSI Primary Commands-4 (SPC-4) (T10/1731-D)NOTE 1 For more information on the current status of these documents, cont
43、act the INCITS Secretariat at 202-737-8888 (phone), 202-638-4922 (fax) or via E-mail at incitsitic.org. To obtain copies of these documents, contact ANSIs Customer Service Department at 212-642-4900, or order from the ANSI Electronic Standards Store at http:/www.ansi.org.Table 1 Standards bodiesAbbr
44、eviation Standards body Web siteANSI American National Standards Institute http:/www.ansi.orgIEC International Electrotechnical Commission http:/www.iec.chINCITSInternational Committee for Information Technology Standardshttp:/www.incits.orgISO International Standards Organization http:/www.iso.chT1
45、0 INCITS T10 SCSI storage interfaces http:/www.t10.orgINCITS 471-201032.4 Other referencesFor information on the current status of the listed documents, or regarding availability, contact the indicated organization.Universal Serial Bus Specification Revision 2.0 (USB-2). April 27, 2000Universal Seri
46、al Bus 3.0 Specification Revision 1.0 (USB-3). November 12, 2008Universal Serial Bus Mass Storage Class Specification Overview Rev 1.3 (MSC). September 5, 2008NOTE 2 For information on the current status of USB documents, see the U SB Implementers Forum at http:/www.usb.org.INCITS 471-201043 Definit
47、ions, symbols, abbreviations, and conventions3.1 Definitions3.1.1 application client: An object that is the source of SCSI commands (see SAM-4).3.1.2 Bulk-in Endpoint Descriptor: A USB Endpoint Descriptor with the BM ATTRIBUTES field set to 02h andbit 7 of the bEndPoint address field set to 1.3.1.3
48、Bulk-in pipe: used to transfer data and status from the UAS target port to the UAS initiator port.3.1.4 Bulk-out Endpoint Descriptor: A USB Endpoint Descriptor with the BM ATTRIBUTES field set to 02hand bit 7 of the bEndPoint address field set to 0.3.1.5 Bulk-out pipe: used to transfer data and comm
49、ands from the UAS initiator port to the UAS target port.3.1.6 Default pipe: The message pipe created by the USB System Software to pass control and status infor-mation between the host and a USB devices endpoint zero (see USB-2).3.1.7 Information Unit (IU): An IU is a formatted collection of data that carries command, task managementfunction, sense, reponse, read ready, or write ready information (see6.2).3.1.8 logical unit number (LUN): A 64-bit identifier for a logical unit (see SAM-4).3.1.9 Pipe: A logical abstraction using USB endpoints representing an associati
