Help about SIM900 gsm module using with atmaga8

[NAYYERBABA]

Hi e
I'm new to gsm communication system please help me i'm using sim900 gsm module with atmega8 & set the baud rate 9600 kbps but modem not respond i think i wrong with baud rate.
any know about that please help me
thanks

 

[raviypujar]

Hi e
I'm new to gsm communication system please help me i'm using sim900 gsm module with atmega8 & set the baud rate 9600 kbps but modem not respond i think i wrong with baud rate.
any know about that please help me
thanks

Hi,
Please check and verify your modem is alright. Connect to a PC and check the commands on a hyperterminal software. Then if the modem is responding go ahead and interface the controller. make sure you have given the right power supply between 3.6 to 4.5V

 

[babar_ali]

i think i wrong with baud rate.

Did you read the data sheet of sim900? The modem has an autobaud rate detection. All you have to do is to write AAT when you ist time boot up the device. When you send "A" the modem adjusts its self to Autobaud rate and give response to AT command.