Rockwell Automation 1770 DH,DHII,DH485 CABLE User Manual
Page 119
Constructing RS-232-C and
Longline Cables
Appendix A
A-7
Figure A.7
Connecting a module to data terminal equipment (DTE) with handshaking.
2
3
4
5
6
7
8
20
25
1
3
2
5
4
20
7
11
6
1
AA
BB
BA
CB
CA
CC
AB
CD
CF
RS-232-C
Connector of
1773-KA, or
1775-KA,
Module
RS-232-C
Connector or DTE
RS-232-C
Pin Assignments:
AA Protective Ground
AB Signal Ground
BA Transmitted Data
BB Received Data
CA Request to Send
CB Clear to Send
CC Data Set Ready
CD Data Terminal Ready
CF Received Line Signal Detector
25-pin Male
Connector
25-pin Male
Connector
12537
8
Important: For the 1775-KA module, you do not have to ground pin 25 as long
as switch 3 on the module is turned on (closed).
Figure A.8
Connecting a module to data communication equipment (DCE) without
handshaking.
2
3
4
5
6
7
8
20
25
1
2
3
4
5
6
7
8
20
1
AA
BA
BB
CA
CB
CD
AB
CF
CC
RS-232-C
Connector of
1773-KA, or
1775-KA,
Module
RS-232-C
Connector or DCE
(E.g. a modem)
RS-232-C
Pin Assignments:
AA Protective Ground
AB Signal Ground
BA Transmitted Data
BB Received Data
CA Request to Send
CB Clear to Send
CC Data Set Ready
CD Data Terminal Ready
CF Received Line Signal Detector
25-pin Male
Connector
25-pin Male
Connector
12538
Important: For the 1775-KA module, you do not have to ground pin 25 as long
as switch 3 on the module is turned on (closed).