Overview
The project aims to develop a GSM alarm unit that can be controlled by BasicX24 stamp module.
Details
In the design, the BX24 board has been connected to a Siemens C35 cell phone and uses AT commands through serial interface for communication. The motion detection is done through PIR sensors and during detection, an SMS to a specified cell phone is sent by the system. There are two ports in BaseicX24 used for communication with the cell phone and these ports were configured to function like RX & TX of COM3. To detect movement similar to cheap light sensors, another port was used as input to the PIR sensor.
A pair of 9V batteries was connected in parallel with a 9V power supply as they provide power to the BX24 and PIR sensor. To keep the Siemens C35 charged, an old 5V Samsung cell phone charger was dismantled and used as the other power supply. This would be enough to keep the alarm online for a few hours when the power stored for the microcontroller, PIR sensor, and cell phone goes down. The SMS sent is n SMS stored in the phone memory.
http://www.circuit-projects.com/miscellaneous-circuits/basicx-stamp-used-for-gsm-alarm.html
