Omron NT631 Operation Manuals page 138

Connecting to the Host's RS-422A/485 Port
Reference
130
Connection to
Communication board
Port A
* When using C200HE(-ZE), the range for PT unit numbers is 1 to 3.
There are no communication boards for which port B is the RS-422A/485 port.
[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), or
Set to [2] (2-wire type, for RS-485)
Switch 2 : Set to "ON" for terminator ON (termination resistance applied)
S Connecting to CS1 series serial communication board
INNER board with RS-422A/485 port equipped for CS1 series CPU type :
CS1W-SCB41-E (The port 2 is RS-422A/485 port.)
[Setting the front switches]
RDY
COMM1
COMM2
Port 1
RS-232C
OFF
2
Port 2
RS-422A/485
SCB41
[Allocation DM area settings for CPU]
Settings are written from the peripheral tool (a programming console or CX-Pro-
grammer) directly into the allocation DM area (system setting area) of the CPU.
After settings are written, they become effective by turning the power ON, re-
starting the unit, restarting the communication port, or executing the STUP com-
mand.
In the following, the channel numbers of the allocation DM area and settings are
shown.
Word # Writing Value
DM6555 5j00
Terminal resistance setting switch (TER)
When this port is at the end of the
communication cable:
"ON" (Terminal resistance is present.)
PORT1
When this port is not at the end of the
communication cable:
"OFF" (Terminal resistance is not
present.)
ON TERM
4 WIRE
Two wire type/four wire type changeover switch (WIRE)
For RS-422A : "4" (4 wire type)
For RS-485 : "2" (2 wire type)
PORT2
(RS422/
RS485)
Section 5-2
Setting
Use NT link (1:N)
j = highest unit number of the
*
connected PTs (1 to 7)