TaeyangGangchiYeog Repairs / 2026-05-18 21:39:46

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 (images partly from scsikabel.com)
Names Photos Versions Types Pins Comments
CN50 SCSI-1 Male 36 (1 row) Similar to the 36-pin connector used by Centronics for the parallel interface on their printers.
DB25 SCSI-1 Male 25 (2 rows) Available on many vintage computers, like the Amiga, via the DKB RapidFire Zorro II SCSI-2 controller.
DB50 SCSI-1 Male 50 (3 rows) Actually, a DD50 connector.
HPDB50 SCSI-1 Male 50 (2 rows) Half-pitch DB50, also called HDB50 (?!) and HDDB50 (high density DB50).
HDI-30 SCSI-1 Male 30 (6 rows) High Density Interconnect for Apple Macintosh only.
HDCN60 SCSI-1/SCSI-2 Male 60 (1 row) High-density Centronics.
HPCN50 SCSI-1     Half-pitch Centronics.
HD50 SCSI-2 Male   High density
HPDB68 SCSI-2/SCSI-3 Male 68 (2 rows) Half-pitch DB68 for Wide SCSI-2, also known as SCSI-3
HDCN68 SCSI-2/SCSI-3 Male 68 (1 row) High-density Centronics 68 pins.
VHDCI "SCSI-5" Male 58 (1 row) Very High Density Cable Interconnect, also known as an HPCN68 (half-pitch Centronics 68 pins). (SCSI-4 is not a thing...)

 

Model 611