SIM808 GSM/GPRS/GPS Modem Interfacing with ATmega32
In this project, we will learn SIM808 GSM/GPRS/GPS Modem Interfacing with AVR ATmega32 Microcontroller. Here, we will interface a SIM808 GSM/GPRS/GPS modem with ATmega32 microcontroller and we will display the status of the SIM and SIM808 GSM/GPRS/GPS modem in a 16X2 alphanumeric LCD.
The SIM808 GSM/GPRS/GPS modem sends some modem and SIM status data when the GSM/GPRS modem is turned on. From this modem status data, we can know in which mode the SIM808 GSM/GPRS/GPS modem will operate:- Minimum Fincationality Mode, Full Funcationality Mode or Aeroplane Mode. And whether the SIM808 GSM/GPRS/GPS modem is ready for call/SMS/GPRS operation or not. By default, the SIM808 GSM/GPRS/GPS modem operates in Full Funtionality mode. From the SIM status data, we can know whether SIM card is present or not and if SIM card is present, then whether it needs any password(SIM PIN, SIM PUK and others ) or not. The communication between SIM808 GSM/GPRS/GPS modem and ATmega32 microcontroller takes place through USART communication protocol. Now, when the SIM808 GSM/GPRS/GPS modem is turned on, the ATmega32 microcontroller reads the initial status data sent by the SIM808 GSM/GPRS/GPS modem through USART protocol. After reading the status data, the ATmega32 microcontroller processes the SIM808 GSM/GPRS/GPS modem status data and displays the status of the modem and SIM in the alphanumeric LCD. If SIM card is not present, then "Plz Insert SIM" is displayed, if SIM card is present and modem is ready, then "SIM900 is Ready" is displayed and for other conditions, "SIM900 Error" is displayed in the alphanumeric LCD.
Now, check the status message in the 16X2 alphanumeric LCD with and without SIM card in the SIM tray of the SIM808 GSM/GPRS/GPS modem.