How do I start this?

[Todd_Whitehead]

I would recommend getting an Arduino Mega and a Smart Things Shield (Assuming they ever come back in stock… if they don’t, this will be much more complicated…)

If you can get a Smart Things Shield, you can attach it to the Arduino. Then, you can take the wires from your ancient alarm system, ti all of the “ground” wires together and attach them to ground on the Arduino and then connect the “positive” wires to individual pins on the Arduino.

Then, use @ogiewon 's garage door opener project as a base.

Arduino SmartShield Garage Controller

@sgonsalves I have been working on an Arduino project as well based on Steve’s original work. I now have created three “Device Types” and one “Smart App” plus the Arduino code to achieve something very similar to what you’re looking for. Each of the contact sensors (I have 6 currently) is exposed as either a Virtual Garage Door Tile (which accepts button presses and shows all four door states on its Garage Door Tile as well as having a traditional contact sensor tile for compatibility with other SmartApps) or a Virtual Contact Sensor for normal doors. I have created an Arduino Device Type, a Virtual Garage Door Device Type, a Virtual Contact Sensor Device Type, and a Smart App to handle the multiplexing/demultiplexing between the Arduino and Virtual Devices. I have also modified Steve’…

You can remove the garage door buttons and sensors from the code and just use the door sensors. You can expand and rename them to match your house.

Then, look at @geko 's Smart Alarm

[OBSOLETE] Smart Alarm is here

Current Smart Alarm version is 2.4.2. Please follow this thread for updates: Like many others, I’m interested in using SmartThings as a cheap substitute for a self-monitored alarm system. I tried using “Smart Security” app, but was not very happy with it. So I wrote “Smart Alarm” - a multi-zone virtual alarm panel. It features: Up to 16 independent security zones Unlimited number of sensors (contact, motion, fire, moisture) per zone Two arming modes - Away and Stay Optional entry and exit delays Zones can be designated as Interior (armed in Away mode only) Exterior (armed in both Away and Stay modes) and Alert (always armed) Zone bypass allows quickly exclude select zones Setting of an alarm can activate sirens, turn on light switches, send push notifications and text messages Silent …

The door lock part is the easiest, there are many to choose from that work well with ST out of the box.

Read through some of these threads and reply back if you have questions.

Good luck!
-Todd