Rockwell Automation 1770-M12 Mass Storage Systems - Manual (Page 55)

Pin Assignments
Appendix C
CĆ2
Pin Number Abbreviation Signal
38 Acknowledge ACK
40 Reset RST
42 Message MSG
44 Selector SEL
46 Command Data C/D
48 Request REQ
50 Input/Output I/O
All odd pins (except pin 25) connect to ground. Either leave pin 25 open or
connect it to ground.
Reference: American National Standard X3T9.2/82–2
Table 1.F
RS422 Pin Assignments
Pin Number Signal Abbreviation
1 Shield Shield
2 Signaling Rate Indicator SI
3 Spare Spare
4 Send Data SD
5 Send Timing ST
6 Receive Data RD
7 Request to Send RS
8 Receive Timing RT
9 Clear to Send CS
10 Local Loopback LL
11 Data Mode DM
12 Terminal Ready TR
13 Receiver Ready RR
14 Remote Loopback RL
RS422 Interface