I have a sim808 module from itead and I tried to put it to work but it doesn't work.
I Follow the recommendations of your site (wiki) I downloaded the
libraries, I tested with both the arduino Mega as with the UNO, but
nothing!?!? I'm desperate to put the module in function to a project, but I can't!
What I'm trying to do is communicate by GSM. Receive or send SMS using the examples of library I have a gsm card and I removed the pin. I have a Li-On battery of 3.7 V @ 1100mAh placed in the module. I called the Rx Tx pin (Uno) in 2 and 3. On the 18 and 19 Mega put in. I called a power supply 9V dc @ 2A. I plugged the antenna the connector gsm!
I plugged the GND PIN to GND pin on the arduino and the VIO PIN to the Vcc pin on the arduino. Didn't do more links!?
I hit the power button of the module. tested and gives error.