SCSI is realized by a bus slot on the motherboard. Just to put a card called host adapter to the motherboard. From this card is a managed data cable. This cable connects individual SCSI peripherals. Each of this peripherals has its own sequencer which is functional independent. Operation on data cable (bus SCSI) is controlled by the host adapter. This makes it possible to install internal or external components. Transferring data on the SCSI bus is managed by the host adapter. The CPU is not loaded by transferring data.