Mitsubishi Electric MELSEC iQ-R Series Reference Manual page 25

Output module
The output module's external output value (ON/OFF) is updated at the inter-module synchronization cycle start timing. (The
output value is updated only once during the inter-module synchronization cycle.) By setting the output value from the inter-
module synchronous interrupt program, several modules can output the setting value externally at the same value. The
external output value is updated at the start timing of the inter-module synchronization cycle after the output that is set in the
inter-module synchronous interrupt program.
Inter-module
synchronization cycle
Inter-module synchronous
interrupt program
CPU module
Input Operation
refresh processing
External output
ON
signal from Y0
Y0
ON
Update an output value.
External output
OFF
signal from Y1
Y1
OFF
D/A converter module
After execution of the inter-module synchronous interrupt program is completed, the output preparation process is executed
suing the digital value set in the D/A converter module. The analog signal is output at the start timing of the next inter-module
synchronization cycle after the inter-module synchronization cycle. (The output preparation process is executed only once
during the inter-module synchronization cycle.) By writing the digital value from the inter-module synchronous interrupt
program to multiple D/A converter modules, multiple modules can output the analog signal at the same timing.
CPU module
Analog output module No.1 CH1
Analog output signal
Internal processing
Digital value
Analog output module No.2 CH1
Analog output signal
Internal processing
Digital value
For details on the inter-module synchronization function in the D/A converter module, refer to the following.
Manual for each D/A converter module
■Precaution
If the inter-module synchronization cycle is too short and the output preparation process has not been completed by the start
timing of the next inter-module synchronization cycle, the D/A converter module outputs an error.
Inter-module synchronous
interrupt program
Normal program
Output Input
refresh refresh
Set an output value.
OFF
ON
OFF
OFF
Update an output value.
ON
ON
Inter-module
synchronization cycle
Inter-module synchronous
interrupt program
Normal program
Input Operation Output
refresh processing refresh
Set a digital value.
Digital value 2
Output preparation
processing
Digital value 1
Output preparation
processing
Digital value 1
Inter-module
synchronization cycle
Normal program
Operation Output
processing refresh
Set an output value.
ON
OFF
ON
Update an output value.
OFF
Inter-module
synchronization cycle
Inter-module synchronous
interrupt program
Input Operation Output
refresh processing refresh
Digital value 2
Digital value 2
5.1 Fixed Cycle Synchronization Function
Normal program
Set a digital value.
Digital value 3
Output preparation
processing
Digital value 3
Output preparation
processing
Digital value 3
5 FUNCTION
5
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