外置SCSI接口引脚定义(差分信号方式)
SCSI 是 Small Computer System Interface 的缩写，外置式 50 针接口的外观为母插座：
连接电缆插头为 50 针公插头：
引脚定义
Pin
Name
Dir
DescripTIon
01
GND
Ground
02
+DB0
+Data Bus 0
03
+DB1
+Data Bus 1
04
+DB2
+Data Bus 2
05
+DB3
+Data Bus 3
06
+DB4
+Data Bus 4
07
+DB5
+Data Bus 5
08
+DB6
+Data Bus 6
09
+DB7
+Data Bus 7
10
+DBP
+Data Bus Parity (odd Parity)
11
DIFFSENS
?
???
12
res
-
Reserved
13
TERMPWR
TerminaTIon Power
14
res
-
Reserved
15
+ATN
+AttenTIon
16
GND
Ground
17
+BSY
+Bus is busy
18
+ACK
+Acknowledge
19
+RST
+Reset
20
+MSG
+Message
21
+SEL
+Select
22
+C/D
+Control or Data
23
+REQ
+Request
24
+I/O
+In/Out
25
GND
Ground
26
GND
Ground
27
-DB0
-Data Bus 0
28
-DB1
-Data Bus 1
29
-DB2
-Data Bus 2
30
-DB3
-Data Bus 3
31
-DB4
-Data Bus 4
32
-DB5
-Data Bus 5
33
-DB6
-Data Bus 6
34
-DB7
-Data Bus Parity7
35
-DBP
-Data Bus Parity (odd Parity)
36
GND
Ground
37
res
-
Reserved
38
TERMPWR
TerminaTIon Power
39
res
-
Reserved
40
-ATN
-Attention
41
GND
Ground
42
-BSY
-Bus is busy
43
-ACK
-Acknowledge
44
-RST
-Reset
45
-MSG
-Message
46
-SEL
-Select
47
-C/D
-Control or Data
48
-REQ
-Request
49
-I/O
-In/Out
50
GND
Ground
