rtd cpuModule CMC6686GX, User Manual

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Facing
P1
or CN7’s connector pins, the pinout is:
RS422 or RS485 Serial Port
You may use Setup to configure the first serial port as RS422 or RS485. In this case, you must con-
nect P1or CN7 to an RS422 or RS485 compatible device.
When using RS422 or RS485 mode, you can use the port in either half-duplex (two-wire) or full-
duplex (four-wire) configurations. For half-duplex (2-wire) operation, you must connect RXD+ to
TXD+, and connect RXD- to TXD-.
RS422 and RS485 Mode Pinout
The following table gives the pinout of connector P1or CN7when RS422 or RS485 modes are en-
abled.
9 7 5 3 1
GND DTR TXD RXD DCD
GND RI CTS RTS DSR
10 8 6 4 2
NOTE! A 120 ohm termination resistors is provided on the cpuModule. Termi-
nation is usually necessary on all RS422 receivers and at the ends of the
RS485 bus.
If the termination resistor is required, it can be enabled by closing jump-
er JP1.
Connector
P1 or CN7
in RS-422/485 Mode
Pin Signal Function in/out DB9
1 -- Data Carrier
Detect
-- 1
2 -- Data Set Ready -- 6
3 RXD- Receive Data (-) in 2
4 TXD+ Transmit Data (+) out 7
5 TXD- Transmit Data (-) out 3
6 RXD+ Receive Data (+) in 8
7 -- Reseved -- 4
8 -- Reseved -- 9
9,10 gnd Signal ground out 5