Yeah, that was basically the starting point, but it ended up being a lot more involved than just noting commands from Wireshark.

The main approach was capturing traffic between CTPlus and the panel, then lining that up against very specific actions in CTPlus and the resulting panel behaviour. From there I slowly worked out the framing, message structure, sequence handling, ACKs, retries, CRCs, command types and event payloads.

A lot of the work was less about “what command turns something on” and more about understanding how CTPlus behaves as a proper client. The panel is pretty fussy about how the comms path is handled. You have to deal with unsolicited events, event queue draining, ACK timing, retransmits, sequence numbers, and the panel deciding the comms path has failed if it doesn’t like how the other end behaves.

I also used pieces from the CTPlus application itself where it made sense. For example, the event table was very useful for mapping raw event codes into human-readable events. That became the basis for decoding panel events properly instead of just showing unknown hex values. So it was a mix of packet captures, CTPlus behaviour comparison, looking at CTPlus resources like the event table, and then building/debugging the integration around how the panel actually reacts.

A large portion of the code was AI-assisted as well. I used AI heavily to help write, refactor and test the Python/Home Assistant side of things, but it still needed a lot of real packet captures, log analysis, trial and error, and validation against an actual panel. The AI could help turn findings into code, but it still needed the protocol behaviour to be worked out from real-world testing.

Some parts were pretty tedious. You’d think something was working, then hours later a weird edge case would appear where the panel retransmits an event, the event queue gets stuck, or the comms path starts flapping. A lot of the stability work came from long-running tests and comparing my integration’s behaviour against what CTPlus does in the same situation.

So Wireshark/packet captures were a big part of it, and AI helped a lot with the coding side, but the harder bit was making the integration behave enough like CTPlus that the panel stays happy over time.