The design of SMS alarm system on CORTEX M3+SIM900A

System based on CORTEX M3 core board and high performance industrial GSM/GPRS module SIM900A as the core of design, design a kind of automatic SMS alarm smoke gas detection system. The core board processor system using STM32F103 as the core controller, communication module and GSM/GPRS module to send and receive data through the asynchronous serial port UART; measurement of smoke gas detection module is used for gas concentration sensor MQ-2. In the measurement system, if the gas concentration exceeds the set value, the processor to control the SIM900A module to send alarm messages to the relevant personnel prompt. The system realizes that the design of the automatic SMS alarm system hardware design, small size, low power consumption; software design, serial communication to send and receive characters were packed, no garbled. After testing, the system performance is good, has a good application in alarm or gas concentration detection situations require unattended in the household gas detection.