Constant (CODE) values in rungs are ALL ZERO
This happened after one of the times that the software indicates that the P1 dropped out of RUN mode and then back into RUN mode during a RUN-TIME TRANSFER.
I know when this happens because my HMI menu handler (snippet pictured) fails to work. Power cycle recovered. -- Glad that the machine was NOT in process at the time.
The error log has three watchdog timeouts for today - all of which have happened during a runtime transfer. Normally, the scan time is about 1.2 mSec.
14MAY19 09:44:05 E03901 Watchdog TimeoutE:67 is the (last) error history entry
Not every runtime transfer will have this WTD error.

since power cycle
Peak Scan Interval 48
Peak Logic Scan Time 19

Hardware config Max scan interval 500 mSec

600 bytes retentive

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