Serial

The documentation talk about a serial port. Look at connection, and check what settings (baud et al) it uses, wheter it is 3.3/5 volt TTL, RS 232, RS 485.

And most importantly, see what it is telling us.

If I can get the software (looks like some Windows software) then I can read all the serial in and out and see what the protocol is.

Bluetooth

The bluetooth dongle, seems to connect to not just my android phone, but my laptop and desktop too. However I can’t seem to connect to it. ie, its probably not a standard Bluetooth profile. I should still be able to connect direct and see.

Windows

I don’t currently have a USB/RS485, ordered

Embedded CPU

The ESP32 I have has a RS485 connection, going to do a capture of all serial data from that. No idea the board rate, but most RS485 uses 115200 unless long distance.