On Sun, 1 Dec 2019 01:06:00 -0800 (PST), Lee Nowell
wrote:

The software side of things I am fine with.

Could be handy then. ;-)

The software architecture of the ESP32 is much better than the ESP8266.

Ok.

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

Hardware, electrics / electronics or all?

Also, know very little about house alarms.

The thing is, there are so many, ranging from the very simple to the
highly sophisticated it might be tricky to know the operational
details on all. However, if you think of them like a 4/ engine that
hasn't really changed for 100 years, alarms can be quite easy.

Basically you will generally have a central box where (historically)
all the wiring would join and with a key then keypad to enable it.
Wireless has removed most of the wiring (to sensors and the like) and
then you go 'smart' where you can manage it on an app (like HIVE
heating etc).

I did build a Maplin Electronics alarm kit but then bought a
commercial one for reasons I can't remember. It has a remote keypad in
the bedroom so you can set / unset various zones when in bed and get
audible / visual indication if a zone is tripped (inc the external
doors).

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

The link I sent to the company website seems to have a board that you wire into the existing alarm system which allows the existing one to trigger the alarm.

The one I say you took out their 'panel' and wired in the new
replacement, plus the GSM module if you wanted?

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). ;-)

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. ;-)

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?

Cheers, T i m