Connector Pinouts - Digital Equipment Digital AlphaStation 200 Series Technical Information

Table 10-19. SCSI Connector Pinouts
Signal Internal
DB0\ 2
DB1\ 4
DB2\ 6
DB3\ 8
DB4\ 10
DB5\ 12
DB6\ 14
DB7\ 16
DBP\ 18
Ground 20
Ground 22
Reserved 24
TERMP 26
WR
Reserved 28
Ground 30
ATN\ 32
Ground 34
BSY\ 36
ACK\ 38
RST\ 40
MSG\ 42
SEL\ 44
C/D\ 46
REQ\ 48
I/O\ 50

Connector Pinouts

Pin 36 on the Digital AlphaStation Series system's external SCSI connector controls an
active SCSI terminator. When an external cable is plugged in, a low-level ground is
sensed on this circuit, which disables the on-board terminator. In this case, a device at the
end of the external SCSI cable must provide far-end bus termination.
External Signal Internal
26 Ground
27 Ground
28 Ground
29 Ground
30 Ground
31 Ground
32 Ground
33 Ground
34 Ground
35 Ground
36 Ground
37 Reserved
38 Open
39 Reserved
40 Ground
41 Ground
42 Ground
43 Ground
44 Ground
45 Ground
46 Ground
47 Ground
48 Ground
49 Ground
50 Ground
Connector and Cable Information
External
1 1
3 2
5 3
7 4
9 5
11 6
13 7
15 8
17 9
19 10
21 11
23 12
25 13
27 14
29 15
31 16
33 17
35 18
37 19
39 20
41 21
43 22
45 23
47 24
49 25
10-21