SIM900 and STM32 programming problem

[Bob_C]

Hi,

Does anyone have any STM32 C code for programming the SIM900. The code I've written uses interrupts but receives a lot of rubbish back in response from the modem. I continually send AT, and then it initially responds with AT. I would have been expecting OK.

When I send further commands it replies with rubbish "1818181E9E60" (hex values of the returned characters)

I'd really appreciate any help.

Thank You
Bob

 

[asimov_18]

Hi Bob_c
Though its too late to reply back to this message. but the modem response is correct
it will send back the string sent to it(echos back).
One needs to suppress the echo back feature using command
"ATE0" (use these 4 character only don't use AT+ATE0)
the local echo back feature will get disabled!!! and then you will get only OK command
as response from the modem.

Asimov