Universal Serial Bus Mass Storage Class Bulk-Only …

1 Universal Serial BusMass Storage ClassBulk- only TransportRevision 31, 1999 Revision 31, 1999 USB mass Storage Class bulk only TransportPage 2 of 22 Change HistoryRevisionIssue 23, 1998 Initial draft, 6, 1998 Revisions made at the mass Storage DWG review Irvine, 21, 1998 Revisions made at the mass Storage DWG review Plano, 5, 1999 Revisions made at the mass Storage DWG review Tigard, 1, 1999 Additions of LUN support - Milpitas, [RC1]March 5, 1999RR review - Midway, [RC2]March 23, 1999 Revisions from reflector review [RC3]March 29, 1999 Specification line by line review Milpitas, [RC4]June 21, 1999 Specification line by line review RR21 Milpitas, 31, 1999 Final Revision edits for Released Document SLC, UTUSB Device Class Definition for mass Storage DevicesCopyright 1998, 1999, USB Implementers rights PROPERTY DISCLAIMERTHIS SPECIFICATION IS PROVIDED AS IS WITH NO WARRANTIES WHATSOEVER INCLUDING ANYWARRANTY OF MERCHANTABILITY, FITNESS FOR ANY PARTICULAR PURPOSE, OR ANY WARRANTYOTHERWISE ARISING OUT OF ANY PROPOSAL, SPECIFICATION, OR LICENSE IS HEREBY GRANTED TO REPRODUCE AND DISTRIBUTE THIS SPECIFICATION FORINTERNAL USE only .

2 NO OTHER LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, TOANY OTHER INTELLECTUAL PROPERTY RIGHTS IS GRANTED OR INTENDED OF THIS SPECIFICATION DISCLAIM ALL LIABILITY, INCLUDING LIABILITY FORINFRINGEMENT OF PROPRIETARY RIGHTS, RELATING TO IMPLEMENTATION OF INFORMATION INTHIS SPECIFICATION. AUTHORS OF THIS SPECIFICATION ALSO DO NOT WARRANT OR REPRESENTTHAT SUCH IMPLEMENTATION(S) WILL NOT INFRINGE SUCH Rickey, Phoenix TechnologiesAlan Haffner, Lexar MediaBill Stanley, AdaptecCalaimany Bhoopathi, Shuttle TechnologyCurtis E. Stevens, Phoenix TechnologiesDarrell Redford , Iomega CorporationDave Gilbert, In-System DesignDavid G.

3 Lawrence, Global Technology DevelopmentDavid L. Jolley, Iomega CorporationDavid Luke, In-System DesignEric Luttman, In-System DesignGlen Slick, Microsoft CorporationHiromichi Oribe, Hagiwara Sys-ComCoJan Matejica, PIMC/PhilipsJim Blackson, Y-E Data, IncJim Quigley, Iomega CorporationJohan Craeybeckk, PIMC/PhilipsJordan Brown, Sun MicrosystemsKenny Chu, Hagiwara Sys-ComCoKenichi Hamada, Y-E Data, IncMark Williams, Microsoft CorporationMasayuki Kitagawa, MitsumiMike Chen, CMD TechnologyMike Glass, Microsoft CorporationMike Liebow, eTEK LabsMike Nguyen, TEACMike Poulsen, Iomega CorporationMoto Watanabe, Devanathan, Shuttle TechnologyParamita Das.

4 Sun MicrosystemsPat LaVarre, Iomega CorporationPeter S'Heeren, PIMC/PhilipsRyota Okazaki, NEC CorporationSadao Yabuki, TEACS higeyoshi Hashi, NEC CorporationShing F. Lin, AdaptecSteve Bayless, Hewlett-PackardSteve Kolokowsky, Anchor ChipsSteven Smith, eTEK LabsTerry Moore, MCCITim Bradshaw, Iomega CorpToyoko Shimizu, Y-E Data, IncTrenton Henry, SMSCTroy Davidson, Iomega CorporationTsuyoshi Osawa, TEACYuji Oishi, Hagiwara Sys-Com Co LtdRevision 31, 1999 USB mass Storage Class bulk only TransportPage 3 of 22 Table of Contents1 Specification Overview and Scope .. 52 Terms and Abbreviations .. 63 Functional Characteristics.

5 mass Storage Reset ( Class -specific request).. Max LUN ( Class -specific request).. Packet Transfer Order .. Queuing .. Command 84 Standard Descriptors .. Number .. Serial Number Descriptor .. Descriptors .. Endpoint .. 125 Command/Data/Status Protocol .. Block Wrapper (CBW) .. Status Wrapper (CSW) .. Transfer Conditions .. transport .. 166 Host/Device Data Transfers .. and Meaningful CBW .. CBW .. and Meaningful CSW .. CSW .. CSW .. Error Handling .. Error Handling .. Classes .. Not Device Disagreements .. Thirteen - Host expects no data - Host expects to receive data from the device.

6 - Host expects to send data to the 21 Revision 31, 1999 USB mass Storage Class bulk only TransportPage 4 of 22 List of TablesTable Bulk-Only mass Storage Reset ..7 Table Get Max LUN ..7 Table - Device Descriptor ..9 Table - Example Serial Number Format ..10 Table - Valid Serial Number Characters ..10 Table - Configuration Descriptor ..10 Table Bulk-Only Data Interface Descriptor ..11 Table - bulk -In Endpoint Descriptor ..11 Table bulk -Out Endpoint Descriptor ..12 Table - Command Block Wrapper ..13 Table - Command Status Wrapper ..14 Table - Command Block Status Values ..15 Table - Host/Device Data Transfer of FiguresFigure 1 - Command/Data/Status Flow.

7 13 Figure 2 - Status transport Flow .. 15 Revision 31, 1999 USB mass Storage Class bulk only TransportPage 5 of 221 Specification Overview and ScopeA familiarity with the USB and Specifications and the USB mass Storage Class Specification Overview specification addresses Bulk-Only transport , or in other words, transport of command, data, and statusoccurring solely via bulk endpoints (not via Interrupt or Control endpoints). This specification only uses thedefault pipe to clear a STALL condition on the bulk endpoints and to issue Class -specific requests as definedbelow. This specification does not require the use of an Interrupt specification defines support for logical units that share common device characteristics.

8 Although thisfeature provides the support necessary to allow like mass Storage devices to share a common USB interfacedescriptor, it is not intended to be used to implement interface bridge 31, 1999 USB mass Storage Class bulk only TransportPage 6 of 222 Terms and ConventionsNumbers without annotation are decimal ---------------------------------------- ------- 1, 17, 23 Hexadecimal numbers are followed by an h ---------------------------------------- --- 1Fh, FCh, 38hBinary numbers are followed by a b ---------------------------------------- ------------011b, 101b, 01110010bWords in italics indicate terms defined by USB or by this specification -----------bRequest, DefinitionsCommand Block Wrapper (CBW)A packet containing a command block and associated Status Wrapper (CSW)

9 A packet containing the status of a command a transfer of data IN from the device to the a transfer of data OUT from the host to the RequestRequests from the host to the device using the default ErrorAn error returned by the device indicating that the results of processing further CBWs will beindeterminate until the device is received and controlled internally by the device to the point that the host need no longer beconcerned about amount of the data sent to the host by the device that is RecoveryAn error recovery procedure by which the host prepares the device for further DiagonalCases where the host and device are in complete agreement about the data transfer.

10 See Chapter 6 -Host/Device Data Transfers, for additional information regarding error cases and the "thin diagonal."Revision 31, 1999 USB mass Storage Class bulk only TransportPage 7 of 223 Functional Bulk-Only mass Storage Reset ( Class -specific request)This request is used to reset the mass Storage device and its associated Class -specific request shall ready the device for the next CBW from the host shall send this request via the default pipe to the device. The device shall preserve the value of its bulkdata toggle bits and endpoint STALL conditions despite the Bulk-Only mass Storage device shall NAK the status stage of the device request until the Bulk-Only mass Storage Reset is issue the Bulk-Only mass Storage Reset the host shall issue a device request on the default pipe of: bmRequestType.