SIM900 GPRS shield not working
Posted: Wed Jul 02, 2014 3:16 am
Hi,
I was previously on an existing thread, but asked to move to a new thread. I have been battling with the GPRS shield for 5 days now...
I have the shield plugged into a 5v 2a power supply and have even bought a new one to ensure it is not a power problem. I flicked the swicth to external power.
The antenna is connected properly and I am in a high signal area.
There is no visible surface damage on the board.
i have tried 2 different sims with exactly the same issues. The 2 sims have been tested in a mobile phone and work perfectly.
I have left the jumper switches in the default s/w position.
I have pressed the on button for 2 seconds before the red light comes on. The green light flashes every 800ms, and even if I leave it for over 1 hour, does not connect to a network.
I have run the following AT commands on both sims giving the same value:
AT
OK
AT+IPR=19200
OK
ATD07595xxxxxx; //obviously I put a real number in here in my serial window
NO DIALTONE
AT+COPS=?
+COPS: ,,(0,1,4),(0,2)
OK
I cannot see any other option than this being a faulty shield. Can you please tell me how to get a refund. Thanks,Chris
I was previously on an existing thread, but asked to move to a new thread. I have been battling with the GPRS shield for 5 days now...
I have the shield plugged into a 5v 2a power supply and have even bought a new one to ensure it is not a power problem. I flicked the swicth to external power.
The antenna is connected properly and I am in a high signal area.
There is no visible surface damage on the board.
i have tried 2 different sims with exactly the same issues. The 2 sims have been tested in a mobile phone and work perfectly.
I have left the jumper switches in the default s/w position.
I have pressed the on button for 2 seconds before the red light comes on. The green light flashes every 800ms, and even if I leave it for over 1 hour, does not connect to a network.
I have run the following AT commands on both sims giving the same value:
AT
OK
AT+IPR=19200
OK
ATD07595xxxxxx; //obviously I put a real number in here in my serial window
NO DIALTONE
AT+COPS=?
+COPS: ,,(0,1,4),(0,2)
OK
I cannot see any other option than this being a faulty shield. Can you please tell me how to get a refund. Thanks,Chris