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Tips and questions relating to the GPS modules from SFE
By alpera
Have you experienced something similar to the following?

I have 2 SIM cards from the same network provider.

With one, when I send “at+cpin?” it gives me SIM PIN. That’s OK, I just have to enter my PIN number, and I do, and it says OK. Now, when I do a “at+cpin?” again, it still return SIM PIN. Which means at+cpin? status doesn't change even though it accepted my PIN..

If I plug the SIM card to my cell phone and turn off PIN code and then plug it back to the telit module, it still is responds SIM PIN now, when I enter my PIN it says “incorrect password”..

The other SIM card’s PIN code is not activated by default (from the purchase). So that one works as soon as I plug it in and at+cpin? returns READY..

Do you know if some SIM cards are incompatible and others not. Is there a trick here?

thanks a lot..