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5-1
Section
Connecting to the Host’s RS-422A/485 Port
77
Setting the Front Switches
Port 1
RS-232C
Port 2
RS-422A/485
Terminal resistance setting switch (TERM)
Set to ON (Terminal resistance is present.) (right side)
Two-wire/four-wire changeover switch (WIRE)
4 (4-wire) (right side)
PORT1
ON TERM
4 WIRE
OFF
2
PORT2
(RS422/
RS485)
RDY
COMM1
COMM2
SCB41
Allocated DM Area Settings for CPU Unit
Settings are written from the Programming Device (a Programming Console or
CX-Programmer) directly into the allocated DM Area settings (PC Setup) of the
CPU Unit. After the settings are written, they become effective by turning the
power ON, restarting the Unit, restarting the communication port, or executing
the STUP instruction.
The following table shows the words allocated in the DM Area and the settings.
Allocated DM
word
Value
Settings
Port 2
Value
Settings
DM32010
8000
Host Link mode, 2 stop bits, data length 7 bits,
even parity,
DM32011
0000
Baud rate
9,600 bps.
0007
Baud rate
19,200 bps.
DM32012
0000
Transmit delay time
0 ms.
DM32013
0000
No CTS control
Unit No.0 for Host Link
Using the 1:1 NT Link Method
Compatible Host Units
Some models and series of OMRON PCs have the RS-422A 1:1 NT Link func-
tion built in.
•
The C200HX/HG/HE(-Z)E CPU Units can be connected by the RS-422A 1:1
NT Link method by installing a Serial Communications Board.
•
The CQM1H CPU Units can be connected by the RS-422A 1:1 NT Link method
by installing a Serial Communications Board.
Check the model and series of the PC and the type of installed Serial Commu-
nications Board before making connections.