GSM module SIM900A and Arduino

[Pero2912]

Instead of buying "normal" GSM module that is used for Arduino, I purchased this **broken link removed**. It seemed cheaper and easier to work with. I connected voltage supply and RX/TX pins and started playing with it. But for some reason it doesn't want to estabilish connection with my GSM network nor recognize my SIM card. Anyone had experience with it?

is it possible maybe that since the module is from china it doesn't support mobile networks in europe?

 

[milan.rajik]

You cross connected Rx and Tx pin with Arduino's Tx and Rx pins ?

 

[Pero2912]

Nope... I can communicate nicely via serial port using AT comands.
The LED lamp which should indicate successful connection to the network does not behave like it is connected (it should blink every second if there is no connection and every 3 sec if there is one. I get blink every second)

 

[milan.rajik]

See this page

**broken link removed**

It is mentioned Network Support as CMCC. Maybe your Network is not supported.

 

[shamo]

One problem I faced while making this connection - check if your GSM module has a built in MAX232 IC somewhere (check both sides of the board). If it doesn't, then you need to get a MAX232 IC and then make the connection externally with the arduino