3-5
1: 1 / 1: N connection
3-2  System Configurations
3-2-4 Connection using RS-232C and RS-485 ports (2)
This configuration connects to external devices using the RS-232C port and RS-485 port.
RS-485 port
Signal conversion
RS-485
RS-232C
<Mode selection switch: “0”>
RS-232C port
Yes
 General purpose device
 General purpose device
External device
 External device 
A
 (personal computer, etc.)
External device External device
BCD
CPU
Power 
supply
RS1
With this configuration, the following communications can be performed :
1) Communication between external device A and external device B, C or D (not via the CPU module)
2) Communication between external device A and CPU module
3) Communication between external device B, C or C and CPU module
<1) Communication between external device A and external device B, C or D>
This communication is performed directly, namely not via the CPU module.
RS-485
External device
External device 
A
 (personal computer, etc.)
External device External device
BCD
Transmission speed is 38400 bps (default) for 
both RS-232C and RS-485.  Changing 
transmission speed is done through the user 
program (expansion FB).
RS-232C
CPU
Power 
supply
RS1