Pin assignments of SCSI connecter


Internal (50 pins)

External

(25 pins)

Signal name

Detail

2

8

/DB0

Bit 0 of SCSI data bus

4 21 /DB1

Bit 1 of SCSI data bus

6 22 /DB2

Bit 2 of SCSI data bus

8 10 /DB3

Bit 3 of SCSI data bus

10 23 /DB4

Bit 4 of SCSI data bus

12 11 /DB5

Bit 5 of SCSI data bus

14 12 /DB6

Bit 6 of SCSI data bus

16 13 /DB7

Bit 7 of SCSI data bus

18 20 /DBP

Parity bit of SCSI data bus

20 - N.C.

Not connected

22 - N.C.
24 - N.C.
26 25 TPWR

+5V terminal power

28 - N.C.
30 - N.C.
32 17 /ATN

Attention

34 - N.C.
36 6 /BSY

Bus busy

38 5 /ACK

Handshake acknowledge

40 4 /RSR

Bus reset

42 2 /MSG

Message phase

44 19 /SEL

Select

46 /C /D

Control or data on SCSI bus

48 /REQ

Handshake request

50 /I/O

Controls the direction of data movement

All odd pins

7,9,14,16,18 and 24

GND

Ground