Mitsubishi Electric MELSEC iQ-R Series Reference Manual page 34

If the local station is disconnected, the disconnected station cannot receive synchronous signals from the
master station and this causes an error at the local station. When the error is detected, the CPU module
continues or stops the operation according to the CPU module operating status setting for error detection.
When the CPU module continues to operate, the inter-module synchronization in the local station continues.
However, the CC-Link IE Field Network synchronous communication stops. When the CPU module stops
operating, both the CC-Link IE Field Network synchronous communication and the inter-module
synchronization in the local station stop.
Regardless of whether the CPU module continues or stops the operation, reset the CPU module of the local
station to perform normal synchronization with the master station after the local station is returned. ( Page
43 Program)
■Cyclic transmission in master station and local station
It takes two inter-module synchronization cycles for the local station's input/output refreshing state to be sent. To synchronize
the input/output refreshing between the master station and local station, the master station's input/output refreshing must be
delayed by two inter-module synchronization cycles.
CPU module No.1
System
of the master
station
Network module No.1
(master station)
Network module No.2
(local station)
System
of the local
station
CPU module No.2
An inter-module synchronization function FB is provided to absorb the two-cycle input/output difference. Use
the inter-module synchronization function FBs to create a program to delay the master station's input/output
refreshing by two inter-module synchronization cycles. (Page 40 Program, MELSEC iQ-R CPU
Module Function Block Reference)
5 FUNCTION
32
5.1 Fixed Cycle Synchronization Function
Inter-module
synchronization cycle
Inter-module synchronous
interrupt program
Normal program
Input Operation Output
refresh processing refresh
1 Output refresh
Cyclic transmission
Cyclic transmission
1 Output refresh
Inter-module synchronous
interrupt program
Normal program
Input Operation Output
refresh processing refresh
Data is transferred to another station after two cycles of inter-module synchronization cycle.
Inter-module
synchronization cycle
Inter-module
synchronization cycle
Inter-module synchronous
interrupt program
Normal program
Input Operation Output
refresh processing refresh
Cyclic transmission
2 Cyclic transmission
Cyclic transmission
Inter-module synchronous
interrupt program
Normal program
Input Operation Output
refresh processing refresh
Inter-module
synchronization cycle
Inter-module
synchronization cycle
Inter-module synchronous
interrupt program
Normal program
Input Operation Output
refresh processing refresh
3 Input refresh
Cyclic transmission
Cyclic transmission
3 Input refresh
Inter-module synchronous
interrupt program
Normal program
Input Operation Output
refresh processing refresh
Inter-module
synchronization cycle