No Dialtone sim900

[davidson357]

I've received GPRS/GSM shield but it's not working. eorder0612 suggested I should send a topic to here.
Have anybody some suggestion or clue?

Thanks

Istvan

[will]

Dear friend,
Could you please tell us how you judge the board didn't work? And what have you done after you received the GPRS board? This will help us find the reason of your problem.Wish you can understand.Looking forward to your reply.

[davidson357]

Here are the high resolution photos.

[will]

Dear friend,
We don't understand the meaning of the photos.Could you please tell me what's the problem of the GPRS board you received? Looking forward to your reply

[davidson357]

I've ordered and got the shield and not working.
The green led is blinking coninously (over 2-3 minutes), I've tried another antenna and checked the contacts.
I have another one and it's works perfectly in this configuration (same arduino, same SIM, same code).
If you have any idea please tell me.

Thanks

I

[will]

Dear friend,
Could you please follow our steps to Check the working state of SIM

1, check if everything goes well with SIM
AT+CPIN?
Returned value
AT+CPIN?
+CPIN: READY
OK
--------------------------------------------------------------------------------
Check if SIM was connected to network
AT+COPS？
If you get the following returned value, it has registered to CHN-UNICOM
AT+COPS?
+COPS: 0,0,"CHN-UNICOM"
OK

--------------------------------------------------------------------------------
Check if you can make phone calls with SIM module.
AT+CCALR？
If you get the returned value: 1, it is ready.
+CCALR: 1
OK
--------------------------------------------------------------------------------
N.B if you can’t make phone calls with SIM, you can check if all incoming calls have been barred.
Solution:
AT+GSMBUSY=0
Returned value
OK

[hotkebab99]

Hello,
Look at my thread. I have the same problem.
There is a strange thing converning the antenna...

[davidson357]

It seems ok now.
I haven't got a clue, what was wrogng.
I may had to wait a bit.

Thanks, again.

[hotkebab99]

Look at my topic "SIM900 - No registration to network".
I found a solution with a picture...

[amitray]

I was having the same issue when suddenly a thought came to press the reset button in my SIM900A board. Surprisingly after resetting it started working. Dont know what was the real issue.