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Arduino Burglar Alarm Sends SMS

github.com

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Re: Arduino Burglar Alarm Sends SMS

#31

Post by gouranga »

asmithmd1 wrote: post #29
gouranga wrote: post #7

Earlier quoted context omitted.

Huawei GTM900 Has serial port which takes AT commands. Easy enough to drive it. Costs $20 a shot.

Have you tried one of these out? Where can you buy one?

http://www.rfsolutions.co.uk/acatalog/RFS_GSM_Modules.html

I have tried out. Well documented and you can get the breakout boards for $5 but I forget precisely where. Managed to get it working in UK on O2 pay as you go. Now in junk box :(

Watch out - you need a level shifter if you're using an Arduino or something as it has 3v3 operation. I used an old(er than me) HP lab PSU and a crudely hacked up set of BC548 switches as a level shifter. You need an antenna and a sim socket (my sim was cruely soldered onto 1/0.2 solid wire and plugged into the breakout board header).

Re: Arduino Burglar Alarm Sends SMS

#33

Post by pyoung »

aimatt wrote: post #20
rorrr wrote: post #15

So what's the total cost? - What's the cheapest Arduino board that would work with this sensor? Wouldn't it be cheaper to get a Raspberry Pi? - How much is the power supply? - It would also be cool if there was a way to send SMS over the regular wireless, like with one of those cheap emergency cell phone plans. That would make it a really nice alarm, no need for the internet, and it can work off a PSU even if burglar…

You can get the cheapest Arduino you can find. About $50 total probably. I would love to see this on a Raspberry Pi, but you will likely have to do some 3v3 to 5v translation or use the upcoming Gertboard.

Are there any functional benefits to doing this with a Pi instead of an Arduino?

Re: Arduino Burglar Alarm Sends SMS

#34

Post by sshumaker »

This is really cool. I've actually been working on something really similar.

Early last year, we built a a breadboard with a Teensy microcontroller (instead of an Arduino) to decode signals from off-the-shelf door and window sensors. At the time, we had to reverse engineer the protocol using a oscilloscope. :) The breadboard was tethered to an Android device, which was the brain of the system (and this let us do other cool stuff, like video, networking etc).

We're much further along now (with working prototype units). If you're interesting in this kind of thing, we ARE hiring. :) (http://elarm.com)

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