All SCSI pinouts and SCSI Information

Background

It all started back in 1979 when the diskdrive manufacturer come with the bright idea to make a new transfer protocol. The protocol was named Shugart Associates Systems Interface, SASI. This protocol wasn't an ANSI standard, so NCR join Shugart and the ANSI committee X3T9.2 was formed. The new name for the protocol was, Small Computer Systems Interface, SCSI.

Common Command Set, CCS, was added in 1985. ANSI finished the SCSI standard in 1986. SCSI-II devices was released in 1988 and was an official standard in 1994. SCSI-III is currently not yet official.

Usage

SCSI is used to connect peripherals to an computer. It allows you to connect harddisks, tape devices, CD-ROMs, CD-R units, DVD, scanners, printers and many other devices. SCSI is in opposite to IDE/ATA very flexible. Today SCSI is most often used servers and other computers which require very good performance. IDE/ATA is more popular due to the fact that IDE/ATA devices tend to be cheaper.

Definitions

SCSI

Short for Small Computer Systems Interface. The original SCSI protocol. ANSI standard X3.131-1996. Busspeed 5 MHz. Datawidth 8 bits.

SCSI-II

SCSI-II adds support for CD-ROM's, scanners and tapedrives.

Fast SCSI-II

Uses the busspeed of 10MHz instead of the original 5MHz.

Wide SCSI-II

Uses 16 bits instead of the original 8 bits.

Ultra SCSI-III

Uses the busspeed of 20MHz.

• Novell and Procomp External SCSI connector This interface is nowadays considered obsolete.
• SCSI Cable (Amiga/Mac) 
• SCSI Cable (D-Sub to Hi D-Sub) 
• SCSI External D-Sub (PC/Amiga/Mac) connector 
• SCSI External Centronics 50 (Differential) connector 
• SCSI External Centronics 50 (Single-ended) connector 
• SCSI-II External Hi D-Sub (Differential) connector 
• SCSI-II External Hi D-Sub (Single-ended) connector 
• SCSI External D-Sub (Future Domain) connector Seems to be available on some Future Domain SCSI-controllers only.
• SCSI Internal (Differential) connector 
• SCSI Internal (Single-ended) connector SCSI=Small Computer System Interface. Based on an original design by Shugart Associates. SCSI was ratified in 1986.
• Apple SCSI HDI-30 connector 
• SCSI-III External Hi D-Sub (Differential) connector 
• SCSI-III External Hi D-Sub (Single-ended) connector 
• SCSI External IBM Burndy connector Special invention by IBM for use on IBM RS/6000 and IBM PS/2
• SCSI-III External Hi D-Sub (Differential) connector SCA=Single connector Attachment
• SCSI-III External Hi D-Sub (Single-ended) connector SCA=Single connector Attachment
• SCSI Internal (2.5")