Omron NT31 Operation Manuals page 140

Connecting to the Host's RS-422A/485 Port
- Connecting to a C-series C200HX/HG/HE(-ZE)
[PC system setting area settings]
Write the PC system setting area (data memory) settings directly from a pe-
ripheral tool (e.g. SYSMAC support software) in accordance with the host
model.
Host Model
Port A of C200HX/HG/HE(-ZE)
*1 RS-422A port of the communication board
For details on operations relating to the PC system setting area, refer to the
manual for the PC you are using.
[Setting the DIP switches on a C200HX/HG/HE(-ZE) communication board]
Set the switches on a C200HX/HG/HE(-ZE) communication board as follows.
Switch 1: Set to [4] (4-wire type, for RS-422A)
Switch 2 : Set to "ON" for terminator ON (termination resistance applied)
Word # Writing Value
*1
DM6555 4000
Section 5-2
Setting
Use NT link (1:1)
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