Posts: 1
Joined: Mon Jan 07, 2013 3:40 am

Home sms alarm - Powered by Rpi?

Mon Jan 07, 2013 3:58 am

Hello everyone!

I'm looking for the best way to create an wireless Rpi powered alarm system, with sms functions.

Basically what i need is:
- 2x Wireless movement sensors.
- 3x Wireless door/window magnets.
- A wireless way to arm/disarm the alarm, possibly a keypad or maybe something simpler.
- A way to send a text message from the RPi upon alarm.
- A relay output or two for a siren.

I think i have the text message function figured out by using an 3G usb dongle and python.

Could you recommend the hardware for all wireless functions?
I'm aiming for 433Mhz since it is the standard here.

Best regards,
And sorry if this is in the wrong place!

Posts: 3
Joined: Tue Oct 30, 2012 8:05 pm

Re: Home sms alarm - Powered by Rpi?

Tue Jan 08, 2013 1:05 am

For starters I would suggest you look at the code provided in this post:
http://www.raspberrypi.org/phpBB3/viewt ... 37&t=27788

Secondly I would recommend avoiding wireless sensors if at all possible because of the difficulty with interfacing to them on your own system. I have personal experience with devices in the 433mhz made for HAI systems here is the link for the wireless product page: http://www.homeauto.com/Products/HAIAcc ... reless.asp
Most of the wireless modules work off of a serial interface that identifies which wireless zone has been triggered, you will most likely have to reverse engineer the specific protocol that your device would use. Alternatively you could engineer some sort of ZigBee/Arduino system but I would try to stick with the commercial devices that should be a little more reliable and give you more options for expansion/customization. I would assume this would be the most difficult portion of your project, but well worth it in the long run.

Finally when it comes to your notification method, why not use an email to an SMS gateway that you could send the message through. I don't know what country or network you are on but here is a link to some of the gateways:
Alternately you could try to send an SMS to your email address and see if it goes through what the return address is, or do a google search for "your provider" and "SMS email gateway". This would have to be cheaper in the long run than a 3G dongle assuming you have wifi/internet in your home.

Posts: 119
Joined: Sun Sep 23, 2012 7:19 pm

Re: Home sms alarm - Powered by Rpi?

Tue Jan 08, 2013 9:42 am


Firstly, let me say that I agree on avoiding wireless sensors if possible. They simply aren't reliable enough for my liking.

Having got that out of the way, here's how I did it...

This post holds the code to read the data from a 433MHz receiver. I got a transmitter and receiver from ebay for £1.60.
http://www.raspberrypi.org/phpBB3/viewt ... 17#p237517

You'll need to expand on that to do something when certain codes are received.

The PIR I used also came from ebay, search for this 290628517837
The data rate is different depending on the position of the 3 position jumper inside, the software here works with the middle position.

The software also receives the control codes for the main controlled sockets in the December MagPI article.

If you do decide to go ahead with this, I'd like to see how you get on.


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