We have seen many Electronics Engineering projects use GSM Modem. GSM modems are widely integrated with GSM security system, GSM alarm to provide easy user interaction of user to the embedded project. What is a GSM module? A GSM module lets you to make calls, Send messages, Process messages and calls, Interrupts sing SMS and CALL, inform system status, values, GPS location, alerts etc within the embedded module. This article not actually a project, we have received many requests asking for the detailed explanation of interfacing GSM Module with PIC (One of our visitor Mr.Nohman Khan requested this). So I decided to do a post on that, and it will simplify upcoming GSM projects.
Here I used PIC16f628A, which has only 18 pins but it has inbuilt UART module, this circuit can be used as GSM modem tester.
To test a GSM module/modem we have to connect it to PC and send AT command then check response, but it not possible when we buying this from a shop, this circuit make you to test GSM Module by simply pressing buttons to make call and send SMS.
- GSM modem SIM300
- IC 7805
- LED x3(Green, Red, Yellow)
- Resistor (100Ωx3, 10KΩx3)
- Capacitor (0.1µF, 33pfx2)
- Crystal 20MHz
- Push button
- Dot PCB
- Connecting wires
- 12V DC supply
SIM300 GSM Module
Let’s have a brief look to the embedded wireless module SIM300,
- SIM300 GSM Modem is able to take any GSM network operator SIM card and behave just like a mobile phone with its own unique phone number.
- The RS232 interface lets modem to communicate with RS232 port of PC or compatible embedded system circuitry.
- Implementation of SMS controlled devices, Auto reply; remote control is possible via SIM300.
- The modem can be directly interfaced with microcontroller. It can be used to send, receive and process SMS/ call
- GPRS facility brings internet and FTP connection to your embedded project.
- SMS based Remote Control Systems
- Security Applications and Sensor Monitoring
- GPRS/ TFTP Mode Remote Data Logging