I was looking to integrate the AST Sentinel Intercom system used in my building to allow me to open our front gate remotely and avoid missing packages when I’m away from home.
I looked into off the shelf options such as the ring intercom, but it claimed to be incompatible with my system and I’m not a fan of cloud based solutions anyway. So I looked up the docs for my intercom and found there was quite a lot of detail on the system logic, enough to throw together a proof of concept solution anyway. So I designed a circuit, and with the help of ChatGPT managed to cobble together a basic sketch in arduino for an ESP32 I had laying around.
I’ve now found the time to convert my HA automations into a blueprint, and to formalise everything into a GitHub repo for anyone else who might have the same or similar systems.
Currently the integration is limited to alerting when the intercom rings, and unlocking when a button is pressed in HA. I intend to integrate audio soon by hijacking the intercom handset audio pins, and eventually I’ll get an oscillioscope hooked up to reverse engineer the signals on the data lines so I can hook the ESP32 up directly and get rid of the relays.
Any help or feedback is welcome