Rockwell Automation 1770-M12 Mass Storage Systems - Manual (Page 56)

Pin Assignments
Appendix C
CĆ3
Pin Number Abbreviation Signal
15 Incoming Call IC
16 Select Frequency/Signaling Rate Selector SF/SR 1
17 Terminal Timing TT
18 Test Mode TM
19 Signal Ground SG
20 Receive Common RC
21 Spare Spare
22 Send Data SD
23 Send Timing ST
24 Receive Data RD
25 Request to Send RS
26 Receive Timing RT
27 Clear to Send CS
28 Terminal In Service IS
29 Data Mode DM
30 Terminal Ready TR
31 Receiver Ready RR
32 Select Standby SS
33 Signal Quality SQ
34 New Signal NS
35 Terminal Timing TT
36 Standby Indicator SB
37 Send Common SC
1 Circuit SF and Circuit SR share the same contact number.
Reference: Electronic Industries Association RS-449