I'm currently using a AT&T Prepaid Go Phone SIM with a GPRS V1.0 in the United States. The card does not have a 3G symbol on it.
I cannot get a 3 second green light on my shield indicating a network connection. When monitoring the serial connection all I get back is
yyyyyyyy
RDY
+CFUN: 1
+CPIN: READY
+PACSP: 0
Call Ready
Everything I do to try and send data to test connections gives back a 0 or an error.
Is getting a 3 second green light something I need to establish in software? Can anyone that has a AT&T SIM working show me their code on how they did it? If it's not this particular shield you're using that's fine, I will go buy your shield model if the shield is the problem. Going crazy trying to get this to work.