Figure 9. RS-232 (Type I)-to-PTC cable, P/N 12705-XX1
RS-232 Type I PTC-870IM
TXD 2 2 TXD
RXD 3 3 RXD
RTS 4 4 RTS
CTS 5 5 CTS
DSR 6 6 DSR
GND 7 7 DIGND
CD 8 8 CD
N.C. 9 DS0
DTR 20 10 DTR
RI 22 11 RI
This cable can be set for either RS-232 or RS-422
communication via jumper settings on the PTC’s
motherboard. For RS-422, the first four pins would be
set as follows:
RS-422 PTC-870IM
TXD+ 2 2 TXD+
RXD+ 3 3 RXD+
RXD– 4 4 RXD–
TXD– 5 5 TXD–
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