The first byte of a SCSI Command Descriptor Block contains an operationcodes that specifies the command that the application client is requestingthe device server perform. Descriptions of the assigned operation codevalues and the commands they represent are organized in tables that aresorted numerically based on the operation code value or alphabeticallybased on the command name associated with the operation code. Anexplanation of the operation code tableformat is available if you are unfamiliar with these tables.

SCSI has a rich command language that is used to move data between systems and storage quickly and accurately. Unlike commands used with systems and networking equipment, SCSI commands are rarely, if ever, entered from a command line or graphical user interface (GUI) by an administrator.

Hyper-Text Format Tables

The operation code tables are available in hyper-text format. Included inthe hyper-text are text links that speed the process of locating operationcode values of interest. The following hyper-text operation code tablesare available:

• Traditional SCSI has been superseded by later attachment protocols such as Serial Attached SCSI (SAS) and iSCSI, which build on the earlier SCSI command structure. SCSI History and Uses SCSI grew out of the Shugart Associates System Interface (SASI), developed by a team led by Larry Boucher at floppy disk drive manufacturer Shugart Associates.
• SCSI commands are 6, 10, 12, or 16 bytes long, often followed by an associated data payload. SCSI commands can be transported over just about any kind of bus, and are the default protocol for storage devices attached to USB, SATA, SAS, Fibre Channel, FireWire, and ATAPI devices.

• Alphabetically Sorted Operation Codes
• Numerically Sorted Operation Codes

Plain Text Format Tables

The operation code tables are available in an ASCII plain text format. TheASCII plain text is suitable for FTP transfer to your computer, printing,and local editor inspection. The following ASCII plain text operation codetables are available:

CMD SCSI - Video Results

• AlphabeticallySorted Operation Codes
• NumericallySorted Operation Codes

CAUTION: The information presented at this Web site is not officiallypart of the SCSI standard. Conflicts between the information presentedat this Web site and the applicable SCSI standard or standards must beresolved by formal action of the INCITS T10 Technical Committee. Until suchresolution occurs, the applicable written SCSI standard or standards apply.

SCSI Command Operation Codes - T10

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