Gprs shield 2.0 stops responding


I have gprs shield 2.0 that is working with teensyduino, apparently after some time the gprs shield stops responding, trying to do a software reset doesn’t appear to work (it wont power down/up the shield), only if I manually press the reset button it shuts down (and after that my software power on works).

this is my software power on code:

digitalWrite(serverTurnOnPin,LOW); delay(1000); digitalWrite(serverTurnOnPin,HIGH); delay(5000); digitalWrite(serverTurnOnPin,LOW); delay(1000);

I am 100% sure that the teensy is not the problem here as I checked the D9 voltage, before the modem stops responding this shut off/on code works perfectly.

the usage of this modem is as a tcp constant connection with the following at commands:
AT+csclk=1 (I pull the dts pin when I want to send at commands as the modem is usually in sleep mode.

any advice?


Anything? please guys, I’m desperate


I had exactly the same problem. My netduino device was running for 2 days when it suddenly stopped sending data to my web service via the GPRS V2 shield. It seemed like the network indicator light that flashes green stopped. I could however not restart the shield pressing the reset button on the side. Here are my questions, perhaps someone can help:

1.) Generally when I restart the GPRS shield by pressing the button on the side nothing happens. I keep it in for longer than 2 seconds yet nothing. Should I see something visually when I reset?

2.) In order to get the software restart working via PIN 9 and after I soldered the JP pads together on the board, I can write the code to set it to low and high but yet nothing happens

3.) The only way I could getting the unit to respond again was to pull the power from my netduino and put it back again where after both started working again.

Any ideas??


I tried updating the firmware and it seems better, already 2 days and no problems. Dont know if it will continue to be ok but it is worth the shot.
I used the enhanced sim900 firmware which is on the gprs v2 wiki page

That is good suggestion.