SCSI interface

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SCSI

(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.

FUJITSU INTEGRATES KOFAX VIRTUALRESCAN 3.1 INTO SCANNERS

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.

INTERACTIVE Tidal wave growth of data gluttons

"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.

SEAGATE LAUNCHES 20GB SCSI TRAVAN SOLUTIONS

According to the announcement, an embedded Intel i960 processor and an Ultra SCSI interface on the IDEplex allows attached drives to transfer data at their full speed-up to twice that of standard SCSI subsystems.

Alcita Technologies Unveils IDEplex for CD-ROM and DYD-ROM Integration

Pioneer New Media Technologies is shipping its new DVD-303S, which it says is the first and only 6x DVD-ROM drive with a SCSI interface. It also supports 32x CD-ROM speed for enhanced backward compatibility.

Pioneer Ships 6x DVD-ROM Drive, DVD Jukebox

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.

File backups can be a zip!

Users of the original SCSI interface had reported interconnect problems.

CD-ROM and multimedia: the tax professional's hardware planning guide

Full images transfer to a Mac in 14 seconds via SCSI interface in 24-bit color at 1280x960 pixels.

Digital studio cameras

Since an audio CD player has no SCSI interface, you can't hook it up to a personal computer.

Quenching storage thirst

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.

Native Fibre Channel tape vs. Fibre Channel-to-SCSI converters

The RTL VD-HVDPCI blade is a WIDE SCSI LVD/HVD expander on a PCI bus, each port converts from LVD to a HVD SCSI interface. This expander incorporates a multimode feature that enables the LVD side of the interface to operate in either LVD or single-ended mode.

CompactPCI SCSI LVD/HVD multimode expander blade

The new offering features an Ultra SCSI interface together with 2.3GB of storage capacity.