Abstract

• This research focuses on the construction and control of GSM module with Arduino Mega by using AT commands which are the instructions used to control a modem. The construction of circuit comprises 8-bit microcontroller ATMega-328P, GSM module (SIM 900A), 16x2 liquid crystal display, 4x4 keypad, GSM SIM card and power supply. GSM module is used to communicate with the mobile phone network for calling and messaging purpose. The system used in this research can act as a simple mobile phone using Arduino Mega. GSM module is used as an interface between Arduino and any other mobile phones to make the connections for this system. C++ programming language is used for the codes to operate the whole system. A program code is loaded into the ROM of ATMega-328P microcontroller and runs the commands. The system can make the calls and send the messages to any phone number.