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5-1
Section
Connecting to the Host’s RS-422A/485 Port
82
Switch 1:
Set to 4 (4-wire, for RS-422A), or
Set to 2 (2-wire, for RS-485)
Switch 2:
Set to ON for terminator ON (terminating resistance applied)
Setting Switches on a CQM1H Serial Communications Board
Set the switches on a CQM1H Serial Communications Board as follows.
Wire selection (WIRE): Set to 4 (4-wire, for RS-422A)
or
Set to 2 (2-wire, for RS-485)
Terminator (TERM):
Set to ON for termination ON.
Serial Communications Board
(Inner Board slot 1)
Terminator Switch (TERM)
Set to ON (right side)
Wire Selection Switch (WIRE)
When using RS-422A: Set to 4 (right side) for 4-wire.
When using RS-485: Set to 2 (left side) for 2-wire.
Connecting to CS-series Serial Communications Board
Serial Communications Board with RS-422A/485 port equipped for CS-series
CPU Unit model:
CS1W-SCB41 (The port 2 is RS-422A/485 port.)
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)
For RS-422A: 4 (4-wire) (right side)
For RS-485: 2 (2-wire) (left 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 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.