SCSI host adapter

A SCSI host adapter is a device used to connect one or more other SCSI devices to a computer bus. It is commonly called a SCSI controller, which is not strictly correct, as all SCSI devices have a SCSI controller built into them: the difference between a host adapter and another SCSI device such as a hard disk or CD-ROM is that the host adapter is responsible for transferring data between the SCSI bus and the computer's input/output bus.
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