SCSI interface

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SCSI interface

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(Small Computer System Interface) Pronounced "scuzzy," SCSI is an earlier hardware interface for up to 15 peripherals connected to one expansion card, called a "SCSI host adapter." Introduced in 1986 by Shugart Associates (see SASI), this parallel architecture was replaced by its serial successor (see serial attached SCSI).

SCSI hard drives were used in mainframes, servers and storage arrays in the late 1980s and 1990s because they were very robust. Initially the only kind chosen for multi-drive RAID configurations, less-costly IDE drives were eventually used (see RAID, IDE and SATA).

SCSI Was a Mini-Network
The SCSI bus connects up to 15 devices in a daisy chain topology, and any two can communicate at one time: host-to-peripheral and peripheral-to-peripheral. For more details, see SCSI Architecture Model, SCSI signaling, SCSI connectors and SCSI switch.

A "Scuzzy" Daisy Chain
SCSI enabled multiple peripherals to take up only one expansion slot in the computer.

SCSI Ports
To enable the daisy chain, all SCSI devices had one "in" and one "out" port plus a dial to set the device number. These SCSI-1 sockets are on the back of a 1990s disk drive. See SCSI connectors.
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References in periodicals archive ?
The Fujitsu Imaging Products Group (IPG) has priced the M4097D-VRS scanner (equipped with Adrenaline 650iLV SCSI interface boards) starting at $8,995 U.S.
PC desktop disk interfaces ATA, DMA and IDE don't cut the mustard at the high end of massive data servers, where the SCSI interface has ruled supreme.
"Resellers who build workstations and value-price servers need a cost-effective tape backup drive with a SCSI interface and a high degree of reliability," said Kevin Perry, executive director of Marketing and Business Development for Seagate Removable Storage Solutions.
One version connects to the parallel port between the computer and the printer; the other uses a SCSI interface to store data up to five times faster.
Users of the original SCSI interface had reported interconnect problems.
Full images transfer to a Mac in 14 seconds via SCSI interface in 24-bit color at 1280x960 pixels.
Since an audio CD player has no SCSI interface, you can't hook it up to a personal computer.
On average, a native Fibre Channel tape drive costs around $500 more than the same drive with a parallel SCSI interface. Each native drive requires a dedicated Fibre Channel switch port.
The new offering features an Ultra SCSI interface together with 2.3GB of storage capacity.