SCSI TECHNOLOGY: NCR'S DEVELOPMENT STORY
SCSI is the acronym for Small Computer System Interface. SCSI is
a specification -- American National Standards Institute (ANSI)
standard X3.131-1986 and International Standard (IS) 9316:1989 --
for a peripheral bus and command set. The SCSI specification
defines a high-performance peripheral interface that distributes
data among peripherals independently of the host, thereby freeing
the host computer for more user-oriented activities.
Today, SCSI is s computer-industry standard. Pioneered between
1981 and 1982 by NCR corporation in cooperation with Shugart
Associates, SCSI technology changed the face of computing.
In 1981, NCR joined forces with Shugart to develop an intelligent
interface for disk drives. In December 1981, NCR and Shugart
convinced the X3T9 Standards Committee to adopt SCSI as a working
document for an ANSI interface standard. In April 1982, a
subcommittee led by an NCR representative began work on the new
standard. The subcommittee named the proposed input/output (I/O)
standard the Small Computer System Interface (SCSI) .
During development at NCR's facility in Wichita, Kansas, a select
group tackled the job of putting the proposed standard into
silicon. The developers labored in isolation from other research-
and-development activities -- in a conference room located in an
unoccupied and uncompleted part of the building. Their room was
lined with liquid-chalk boards, also known as "white boards,"
which served as scratch pads for the team. Each time a board was
filled with design notes, a photo was taken to capture the data,
and the board was wiped clean and used again. This design process
yielded the industry's first SCSI chip.
Of course, much has changed since the introduction of the first
SCSI chip. There are now many SCSI protocol chips from which to
choose, almost every computer vendor offers or uses SCSI
products, and the SCSI protocol has now been approved as an
international standard (IS 9316:1989) .Today, NCR continues to
enhance SCSI technology and develop new standards that permit
SCSI to take advantage of emerging technologies.