Deleting SMS from SIM808 GSM/GPRS/GPS Modem with ATmega32
In this project, we will learn Deleting SMS from SIM808 GSM/GPRS/GPS Modem with AVR ATmega32 Microcontroller. Here, we will delete a text message(SMS) from the SIM808 GSM/GPRS/GPS modem memory with ATmega32 microcontroller and we will display the status of the SMS deleting in a 16X2 alphanumeric LCD.
When the SIM808 GSM/GPRS/GPS modem power 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, when the SIM808 GSM/GPRS/GPS modem is ready, the ATmega32 microcontroller will send the "AT+CMGD" AT command( AT+CMGD command is used to delete a SMS) with the memory location to the SIM808 GSM/GPRS/GPS modem. In response to the AT command, the SIM808 GSM/GPRS/GPS modem will a send a response to the ATmega32 microcontroller. The ATmega32 microcontroller will analyse the response and accordingly it will display the status of SMS deleting in the alphanumeric LCD. The alphanumeric LCD will display "SMS Deleted" if the SMS is deleted successfully from the memory location or it will display "Error" if AT command is not executed properly or it will display the "Other Error" other types of error in the SIM808 GSM/GPRS/GPS modem.
Now, delete any SMS stored in the SIM808 GSM/GPRS/GPS modem.