TaeyangGangchiYeog Repairs / 2026-05-10 19:16:48

SCSI Connectors

The Small Computer System Interface (SCSI) was introduced circa September 1981 and first became a standard in June 1986, 30 years ago in June 2026! 

It evolved in three main versions at least: SCSI-1, SCSI-2, and SCSI-3, which should be backwards compatible with one another: SCSI-3 devices can be used with SCSI-2 controllers, and SCSI-2 and 3 devices can also be used with SCSI-1 controllers. Conversely, lower version devices can be used with higher version controllers. The only limitations would be transfer speed.

In addition to different versions, many different connectors were used to connect SCSI devices, with esoteric names such as "half pitch D-subminiature 68-positions male connector". They are divided into two main categories: parallel and serial, which themselves are divided into internal and external. The table below focuses on parallel external SCSI connectors and tries to make sense of this mess as a help to connect various SCSI devices to various computers .

External Parallel SCSI Connectors
Names Photos Versions Types Pins Comments
CN50   SCSI-1 Male 36 Similar to the 36-pin connector used by Centronics for the parallel interface on their printers
DB25   SCSI-1 Male 25  
           
           
           
           
           
           
           

 

Model 611