Our trace shows it rising and falling between two polls. The PLC clears it without an observed acknowledgement. No wonder the application misses it.

@ClaraAli0176 Draft one writer and clear conditions for each field, then review a request retained until matching acknowledgement with the interface owner. That should settle the handshake offline.

Settle it? Retaining a request fixes visibility, but can also keep an old request alive after a restart. Identity and reset rules matter.

@HenryBrooks0786 Yes, I overstated that. Retention addresses the missed pulse. The offline review also needs matching identity, reset ownership and restart cases before the design is complete.

Would your table include who reads each field too? Our notes say used by PLC, which could mean practically anything.

@ClaraAli0176 Yes: writer, readers, meaning, set condition and clear condition. Then give each legal transition a concrete example.

On my interface, both sides cleared acknowledgement for different reasons. Each program looked reasonable alone. Put them together and the answer vanished

@PriyaBarnes0568 I've checked our assignments and found that too: both sides can clear acknowledgement. I'll put both conditions in the review rather than quietly choose one.

The missed pulse is explained, and I've got an ownership review to work from. Our complete handshake behaviour is still open.

@ClaraAli0176 The trace gives the review a concrete starting point. Keeping the overall handshake open is fair.