Has anyone tried BLE communication between ESP32 devices ?
Context:
I’m considering it as a fallback mechnism between an ESP that controls LED lights (DC) and another one that’s an (AC) switch input reader. Wired comms between devices is non-trivial (physically as well as due to the voltage differential), but they are only a few meters apart. Wifi works ofcourse, but I’d love something that works even when that’s down.
I am working on a general solution to this, but it would be possible now with a little coding;
assuming all you need is for a binary sensor on one device to be replicated on another, set up a BLE server on the one with the switch, use the switch (i.e. binary sensor) state to update the BLE server manufacturer data, then on the light controller use the BLE tracker to extract the sensor state from advertising packets from the other device and update a template binary sensor.
The manufacturer data in the server isn’t currently templatable, but you can use an api call in a lambda to update it.