* unknown or not available at this time.

SCSI Connectors FAQ

What connectors are available?
What does centronics or CX mean?
What is HD?
What is IDC?
What is MCX?
What is DB?

What kinds of connectors are available?

I'm glad you asked. Click the links below to see connector pictures.

Internal connector pictures:

MCX-80F(SCA)
MCX-80M(SCA)
HD-68F
HD-68M
IDC-50F
IDC-50M

External connector pictures:

VHDCI-68M(.8mm)
VHDCI-68F(.8mm)
HD-68M
HD-68F
HD-50M
HD-50F
CX-50M
CX-50F
DB-25M
DB-25F
* DB-50
* Mini CX-50
* Mini CX-60(RISC6000)
* Mini CX-68(RISC6000)

* means most civilized SCSI devices do not have these connectors on their devices.

What does centronics or CX mean?

Centronics is a style of connector which uses "plates" instead of "pins". You will never find actual pins on a centronics style connector.

"The "Centronics" connector gets its name today from the fact that the 36-pin connector was first used on the Centronics printer, a popular, low-cost dot-matrix printer first offered back in the sixties." - Walt Foley

What is HD?

HD stands for "High Density". High density scsi connectors are typically "D" shaped and only have 2 rows. The only exception is the HDI-30, which is 5 rows and square. The most common external SCSI connectors today are HD-50 and HD-68. The HD-50 connector usually uses clips and is called SCSI-2 by many hardware vendors. The HD-68 connector usually uses screws and is called SCSI-3 by many hardware vendors. The HDI-30 does not use screws or clips, and it is commonly used with powerbooks.

What is IDC?

IDC is a term that refers to square internal connectors, usually connected to ribbon cables. They are usually black with no hardware. Some of these connectors have keys or knockouts. The IDC 50 is the connector most commonly used with older SCSI devices. As a sidenote, IDC 40 connectors are used with IDE drives, and IDC 34 connectors are used with 3 1/2" floppy drives.

What is MCX?

MCX stands for "Micro-centronics". Micro-centronics connectors are found on SCA drives and some newer high-end SCSI devices and controllers. MCX 80 is commonly referred to as SCA. SCA is short for "single connector attachment" and is being implemented by many hardware manufacturers today. The VHDCI 68 (aka SCSI-5) connector is an MCX style connector. Mini CX 50, 60, and 68 are commonly referred to as "RS6000" connectors, because they were used by IBM in RISC 6000 systems way back when. Caution is need here when looking for Mini CX 68 cables. When a vendor uses the term MCX 68 without RS6000, VHDCI, .8mm, or .5, you need to ask more questions.

What is DB?

DB is the most common style of connector used on computer systems today. Serial, parallel, and SCSI all use DB style connectors. SCSI only uses the DB-25 connector. A DB connector is "D" shaped and typically uses 2 rows of large pins. The DB-50 is an exception, because it uses 3 rows. Be careful when dealing with DB-25 ports. A parallel port and a SCSI port look the same on some computers. (Past experience has shown that plugging a parallel printer into a SCSI port causes damage to all of the devices on the channel, including internal devices.)