I've had a rather frustrating few weeks with the Seeedstudio GPRS Shield v2. I can get the shield to send an SMS most of the time - but I can't for the life of me seem to receive (or at least process) any data from the shield.
Whenever I attempt to GPRS->read(); it only returns a 0.
I am using the Yun, software serial pins 7 and 8 and have a ridiculously simple sketch to that echoes commands from the serial monitor to the shield. I believe I'm correctly terminating the AT command strings with \r\n.
- I'm powering the Yun and shield via USB mini.
- The shield has a network connection: the green power led is on, the red led on, and the green network led is flashing every 3 seconds.
I've attempted without success:
- changing the baud rate between 2400 and 19200.
- changing the pins from 8,7 to 10,11.
I've looked high and low across the internet for help, but found nothing. Does anyone have any thoughts please?
Thanks so much!