Switch Settings - Omron CPM2C Operation Manual

Preparation for Operation
7-3-2

Switch Settings

RS-422/RS-485 Switch
(SW1)
DM Area Setting Switch
(SW2)
Communications Switch
(SW3)
234
Simple Commu-
CPU Unit
nications Unit
When the CPM2C-CIF21 Simple Communications Unit is connected to the
CPU Unit, a computer or Programmable Terminal can be connected to the
RS-232C port on the front of the CPM2C-CIF21. A Programming Console
cannot be connected while the CPM2C-CIF21 is being used because the
CPM2C-CIF21 occupies the peripheral port.
This switch determines whether components are connected to the Simple
Communications Unit through an RS-485 interface or RS-422 interface. When
the RS-485 interface is being used, set SW1-3 OFF and SW1-4 ON so that
data is received continuously.
The following table shows the factory default (RS-485) settings.
SW1 pin Default setting
1 ON
2 ON
3 OFF
4 ON
Sets the starting word of the range DM Area words used to exchange data
between the Simple Communications Unit and CPU Unit. Rotary switch set-
tings 0 to F correspond to starting DM Area words DM 0000 to DM 1500. (The
starting word is set in 100-word steps.)
The following table shows the factory default setting.
Setting Starting word in DM Area
0 DM 0000
Sets the baud rate for communications between the Simple Communications
Unit and the CPU Unit as well as the baud rate and frame format for communi-
cations between the Simple Communications Unit and the components. The
baud rates and frame format set on SW3 must match the settings in the CPU
Unit and components.
RS-422 or RS-485
Up to 32 components
Function
RS-485 interface (2-wire communications)
Reception permitted after sending of data is com-
pleted
Section 7-3