It is the hardware side that I am less comfortable with.

Hardware, electrics / electronics or all?

Good point.... it is the electronics side I am less comfortable. I understand what everything does but then designing a circuit with the right things in the right place not so good.


I would be looking for something as a base to provide the basics,
wired and ideally without a microcontroller and with a circuit
diagram. ;-)

My thinking here is that the software to control the alarm, detect a triggered sensor, manage zones etc etc. is quite involved and is clearly critical to the solution. Unless there is some ESP32 opensource code out there this my be an initial step too far. As a first step it would be easier to let the existing alarm do all of that (that's what it was designed and tested for) and then interface the ESP32 to that. Initially detecting when an alarm is triggered - I assume that something like assuming the ESP is another siren and writing the code to detect the event and do something (e.g. send SMS). As mentioned no idea what the wiring for this would look like. Next step would then be to try and arm/ disarm it using the ESP32. I assume this is a bit like the ESP being a keypad but assume there is some protocol between the keypad and main unit.


The board somehow piggybacks on this and gets notified when the alarm is tripped

That bits is easy (with the ESP32 / GSM module and your coding). ;-)

If you are able to figure that bit out for my (and yours?) alarm I am happy to figure out the SMS coding bit


and also somehow enables the alarm to be set/ disabled via the board.


I have played with the outputs of an ESP32 over WiFi and BT so know
that works as well. Not sure how you would do it via texts though but
I'm sure you might. ;-)

Yes I have done the Wifi connection with ESP32 before and getting it to run a web server so you can interact with it. Have also dabbled with their ESPNow protocol.

The product selection wizard seems to talk about having a free keypad connection on the alarm.

That is also possible (and you can get Arduino based keyboards).
However, a RFID fob might be easier, if you are there, with a physical
keyswitch as a backup / override?


As an initial step was assuming the existing keypads would be used to arm/ disarm but yes moving to something else subsequently would be a good idea. Depending on how the other bits go, in theory there would be all sorts of options e.g. a tablet on the wall, an SMS from the phone, mobile app etc etc.

If you are keen to collaborate and go down the path together, let me know.

I have some ESP32's but not one with the Sim card so would have to source one if we do look at this.

thanks

Lee.