A bit of a long reach this one, but I'm trying to 'emulate' a keypad for a Scantronic 8136 panel. I've got as far as identifying it using a 150bit protocol of what seems to be long and short pulses on the signal wire done through releasing the signal wire from ground and letting the panel pull it back up to +14v for a period of time 150 times synchronised by a clock.

I'm hoping to build on this so that I can control my antique alarm system from my phone!

Anyone have any further information on how this works, as my attempts to play back the pulses (I think) I've copied are ignored by the panel, so I'm missing something!

Imsorry ive never attempted anything like that.

This project may help

2 Bus interface (line driver) hardware · AndySymons/KELLY-Scantronic-994x-Keypad Wiki · GitHub

Yeah, I've seen his work, I believe it's a different device, and I have got further in to the protocol than he did. Thanks for commenting though!

Another project. Id assume the protocol for scantronic panels would be similar