interface sim900 to 8051 to send sms

Hi all,
I am new to this forum.

I am using 8051 to send a sms on sim900
plz help me where i can start

plz help me

Hi,
First understand the sim900 commands format to send the sms through micro controller, and then write the necessary firmware for it.

write 8051 UART firmware and connect the UART Rx & Tx pins with the Modem RX &TX pins,and build the firmware with application structure, and print the reply from the modem with the another USART on the terminal.

Thanks & Regards,
Chandu.Kurapati

Hi billu anand,

as already mentioned by chandu.kurapati you need to work a bit.

but let me explain them step by step ( assuming you are new to microcontrollers, and you have choosen AT89S51 )
1. get a working code of UART communication for 8051 (can be easily found on any blog)
2. make it communicate proper with PC ( COM port of your desktop or any other device having COM port, just to make sure your code is working fine using UART)
3. communicate SIM900 module with PC, to find the correct sequence of sending SMS
a. AT+CMGF=1
b. AT+CMGS="xxxxxxxxx"
c. > message
d. SUBSTITUTE character ( Hyperterm shorcut Ctrl+Z, ASCII 26 )
4. interface SIM900 and 8051 together
5. check if you are able to send SMS or not.

what is your current status, let us know.

Hi billu anand,
what are the commands mentioned by the sau_sol in that post are absolutely working commands, i already worked on this commands with another hi-end micro controller and GSM/GPRS modem.

Thanks & Regards,
Chandu.Kurapati.

refer the following link....
There you can find lot of valuable data.............http://iblocks.in/learning-center/micro-controller/at89c51-8051/at89c51-805132/

billu anand said:

Hi all,
I am new to this forum.

I am using 8051 to send a sms on sim900
plz help me where i can start

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