9
W&T
RS232(/RS422/RS485) Multi Computer Adapter
Subject to error and alteration
Wiring assignments RS232/RS422/RS485 (#85604)
The RS232/RS422/RS485 connection for the modules is
configured as a 9-pin male SUB-D connector. Refer to the follo-
wing tables for connector pin assignments:
RS232 interface RS422/RS485 interface
pin#
signal
function
1
TXD A
output
2
RxD A
input
3
DTR A
output
4
CTS A
input
5
GND
GND
6
TXD B
output
7
RxD B
input
8
DTR B
output
9
CTS B
input
pin#
signal
function
1
DCD
input
2
RxD
input
3
TxD
output
4
DTR
output
5
GND
GND
6
DSR
input
7
RTS
output
8
CTS
input
9
RI
input
Operating modes
The Interface Modules are configurable for the following
modes using DIL switches, which are mounted on the modules:
RS232
The Interface Module converts all available TTL data and hand-
shake signals into RS232 signals. This mode provides one RxD
and TxD channel each in the respective direction, along with
six handshake channels (RTS, CTS, DSR, DCD, DTR and RI).
RS422
The Interface Module supports one data and one handshake
channel each (selectable DTR or RTS handshake output). The
RS422 sender/receivers are always active.
RS485
One data channel in each direction is always available in all
RS485 modes. These modes differ only in how the RS485
transceivers are controlled.
RS485 4-wire bus master
In this mode the master uses a conductor pair to send
requests to the slaves, which in turn send their replies to the
