SIM900A is a GSM module that function like phone. It can send a message, call a phone number and use GPRS to send data. Here’s the simple feature taken from it’s datasheet :

This code sets up communication between an Arduino and a GSM module (SIM900A) using SoftwareSerial. It allows the user to send an SMS or make a call by sending specific characters (‘s’ for SMS, ‘d’ for dialing) through the Arduino’s Serial Monitor.

SIM900A Modem is built with Dual Band GSM/GPRS based SIM900A modem from SIMCOM. It works on frequencies 900/ 1800 MHz. SIM900A can search these two bands automatically. The frequency bands can also be set by AT Commands. The baud rate is configurable from 1200-115200 through AT command.

SIM900A module allows users to send/receive data over GPRS, send/receive SMS and make/receive voice calls. The GSM/GPRS module uses USART communication to communicate with microcontroller or PC terminal. AT commands are used to configure the module in different modes and to perform various functions like calling, posting data to a site, etc.

Mar 13, 2024 · This Arduino code is designed to interface with a GSM module using AT commands for sending SMS messages, receiving live SMS, and making phone calls. The code uses the SoftwareSerial library to create a serial communication interface with the GSM module.

With a little help from a GSM module (like the kind in your cellphone), you can start sending messages and calling from your Arduino project. This article will show you how, step by step. Whether you’re making a smart mailbox, a home alarm system, or just want to learn something new, this guide has got you covered.

Oct 22, 2017 · This blog post provides a good starting point for beginners interested in using the SIM900A GSM module with an Arduino Uno. It clearly explains the basic communication method using AT commands and highlights the necessary components.

Arduino Code – Receiving a Call. Unlike making a call or sending a text message, no special code is required to receive an incoming call using the SIM900 shield. The Arduino simply listens for incoming signals, and when a call is received, it is displayed on the Serial Monitor.

Mar 12, 2023 · In this tutorial, we are going to learn how to interface the SIM900A module with Arduino and also build a call alert system. This circuit will call to a specified number if the button is pressed, so we can use any sensors/triggers instead of the button.

Nov 8, 2020 · In this section, we will learn How to interface GSM module sim900 interfacing with arduino using softserial library, and code to control lights by sending sms to your sim module. SIM900A module work on AT commands.