IOISCSI - SCSI Information

Ą@

SCSI History and Development

SCSI - Small Computer Systems Interface

Before SCSI
SCSI can be traced back to the 1960's when IBM's 360 mainframe machine had an I/O bus that could talk to several different peripheral devices simultaneously.

Over the years, this IBM bus, which became known as the OEM Channel, was modified, enhanced, and presented to the American National Standards Institute (ANSI) for adoption as a standard I/O bus for peripheral devices. Because of the proprietary nature of the OEM Channel, the ANSI committee rejected it, citing the need for a commercially standard parallel I/O bus.

In the early 1980's, Adaptec's founders, while at disk drive manufacturer Shugart Associates, developed a parallel I/O interface called SASI for Shugart Associated System Interface. When this specification was finalized, it was released to several different manufacturers and enjoyed commercial success. In 1982, SASI was presented to ANSI as a basis for standard. Because of the commercial success and widespread market use of SASI, ANSI formalized and extended the SASI specification and changed the name to SCSI (in part to separate the specification from any one vendor in particular). In June 1986, SCSI was formally adopted by ANSI.

What is SCSI?
SCSI is an ANSI standard for connection peripherals/devices to your computer via a hardware interface, which uses standard SCSI commands. SCSI allows for computer components to be easily connected and removed and to communicate in order to complete a desired task.

Why SCSI?
Due to the rise in usage of modern operating system that support multi-threading and multi-tasking (UNIX, Windows NT/95, OS/2), SCSI is becoming the popular standard for connecting devices to your computer. It is important to understand the aspects of SCSI since more and more computers use it daily. In fact, if you have a SCSI connection on your PC, your are able to:

connect the fastest, highest-capacity peripherals
connect multiple peripherals from only one slot
connect external peripherals to your computer
perform MULTITASK! SCSI, the only multitasking interface

[Back to the SCSI index page ]



*Your Total SCSI Partner*