Mitsubishi Electric MELSEC iQ-R User Manual page 134

■Abnormal operation during synchronization
The phenomenon that the A/D converter module cannot receive inter-module synchronization signals at a normal cycle is
called "synchronization loss". When a synchronization loss has occurred, an inter-module synchronization signal error (error
code: 2610H) occurs. When this error has occurred, the synchronization of the A/D converter modules stops and 'CH1
Synchronization digital output value' (Un\G9500) keeps the previously stored value.
The following shows the operation of the A/D converter modules of when a synchronization loss has occurred.
Inter-module synchronization cycle
Module A
A/D conversion timing
Module B
A/D conversion timing
Module A 'CH1 Synchronization
digital output value' (Un\G9500)
Module B 'CH1 Synchronization
digital output value' (Un\G9500)
Inter-module synchronous interrupt
program
Module A, Module B
'Synchronization status monitor'
(Un\G9600)
(1) When the A/D converter module cannot accept the inter-module synchronization cycle, a synchronization loss has occurred.
(2) When the A/D converter module did not accept the synchronization cycle at the timing where the synchronization cycle was supposed to be accepted, an
inter-module synchronization signal error (error code: 2610H) occurs and 'CH1 Synchronization digital output value' (Un\G9500) keeps the previously stored
value.
(3) Once an inter-module synchronization signal error (error code: 2610H) is detected, Inter-module synchronization target (synchronization stopped) (1) is
stored in 'Synchronization status monitor' (Un\G9600).
When a synchronization loss has occurred, the module may be affected by noise. Check and adjust the cable
wiring and the installation environment of the programmable controllers, and restart the system. If the error
reoccurs even after the adjustment, the possible cause is a failure of the module. Please consult your local
Mitsubishi representative.
Monitor
When the inter-module synchronization function is used, the inter-module synchronization status can be monitored.
For details, refer to the following.
Page 243 Synchronization status monitor
1 FUNCTIONS
132
1.18 Inter-Module Synchronization Function
Inter-module
synchronization cycle
Previous A/D
conversion value
Previous A/D
conversion value
Synchronous
interrupt program
Inter-module synchronization target
(synchronization in process) (2)
(1)
(2)
A/D conversion value
A/D conversion value
Synchronous Synchronous
interrupt program interrupt program
(3)
Inter-module synchronization target
(synchronization stopped) (1)