SCSI COMMAND Meaning and
Definition
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A SCSI command refers to a specific instruction or request issued by a host computer to a Small Computer System Interface (SCSI) device. SCSI commands are utilized to control and communicate with various peripheral devices, such as hard drives, CD-ROM drives, printers, scanners, and tape drives, connected to a computer system via a SCSI bus.
These commands form the basis for information exchange between the host and the SCSI devices, enabling the host computer to perform read and write operations, initiate data transfers, retrieve device information, and execute various other data management tasks.
SCSI commands are typically structured using a specific command descriptor block (CDB) format. The CDB encapsulates the necessary information required by the SCSI device to execute the requested operation, including the command code, the logical block address, the data transfer direction, and any additional parameters specific to the particular command.
The execution of SCSI commands involves a variety of stages, including the command transfer from the host to the device, command decoding, command execution by the device, and the subsequent status report back to the host. The SCSI protocol defines a comprehensive set of commands that allow for the efficient control and management of SCSI devices within a computer system.
In summary, a SCSI command represents a communication instruction issued by a host computer to a SCSI device, enabling the host to control and interact with various peripheral devices connected to the SCSI bus.
Etymology of SCSI COMMAND
The acronym "SCSI" stands for Small Computer System Interface. The term "SCSI command" refers to a command sent over the SCSI bus, which allows communication between a computer and peripheral devices such as hard drives, CDs/DVDs, printers, or scanners.
The term and its etymology can be traced back to the development of the SCSI technology in the late 1970s by Shugart Associates System Interface (SASI). Originally, "SCSI" was an acronym for "Shugart Associates System Interface". However, as the technology became standardized and adopted by other companies, it evolved into "Small Computer System Interface", reflecting its broader usage beyond Shugart Associates.
The word "command" itself has its etymology derived from the Latin word "com(m)andare", which means "to order or give control".
