Exchanging Data With The Cpu Unit; Mutual Exchange Of Run Status - Omron SYSMAC CS Series Operation Manual

Exchanging Data with the CPU Unit

When Analog Output
Units C200H-DA003/004,
CS1W-DA08V/C or CS1W-
DA041 and Analog
Input/Output Unit C200H-
MAD01 or CS1W-MAD44
are used
When isolated-type
Control Output Unit
CS1W-PMV01/02 is used
3-3

Exchanging Data with the CPU Unit

3-3-1

Mutual Exchange of Run Status

136
When the operation mode of the CPU Unit changes from RUN or MONITOR
to PROGRAM, the Conversion Enable flag of the Analog Output Unit and the
Analog Input/Output Unit is turned OFF from the CPU Unit, and the output
hold function holds analog output values at the previous value, minimum value
or maximum value.
The Loop Controller forcibly turns this Conversion Enable flag ON when the
Unit is in use.
However, when the CPU Unit changes to the PROGRAM mode, the Conver-
sion Enable flag momentarily (operation cycle of Loop Controller) turns OFF,
and as a result the analog output value is momentarily switched to the
momentary output hold value.
To prevent the analog output value from being switched to the momentary out-
put hold value when the CPU Unit changes to the PROGRAM mode, set the
I/O Memory Hold flag (A50012) of the CPU Unit to ON, and set "Hold ON/OFF
of I/O Memory Hold flag at power ON" to ON in the PLC Setup.
Isolated-type Control Output Units do not have a Conversion Enable flag. Dis-
abling of conversion is indicated by the setting of the allocated Data Memory
area. As the default setting, conversion is executed, and analog output values
are refreshed and output. Conversion is executed at all times as long as it is
not disabled by this allocated Data Memory area (except by a CPU Unit fatal
error).
However, when the CPU Unit changes to the PROGRAM mode, the analog
output value momentarily (operation cycle of Loop Controller) turns OFF, and
as a result, the analog output value is momentarily switched to the lower limit
(minimum) value.
To prevent the analog output value from being switched to the lower limit (min-
imum) value when the CPU Unit changes to the PROGRAM mode, set the I/O
Memory Hold flag (A50012) of the CPU Unit to ON, and set "Hold ON/OFF of
I/O Memory Hold flag at power ON" to ON in the PLC Setup.
The Loop Controller exchanges the following two types of data with the CPU
Unit:
1. Mutual exchange of run status
2. Commands from CPU Unit to Loop Controller
3. Exchange of any data
The run status of the Loop Controller and the CPU Unit can be monitored
mutually by the following two areas:
• Allocated CIO area for CPU Bus Unit:
• System Common blocks (Block Model 000): Run status of the CPU Unit
Section 3-3
Run status of Loop Control-
ler is sent to the CPU Unit.
is sent to the Loop Control-
ler.