cpin not ready on SIM300E

[lor3nzo]

Hi,
we have a problem with SIM300E.
After modem on we receive these unsolicited result codes:

RDY
+CFUN: 1
+CPIN: READY
Call Ready

and the things go right.
But sometimes, after Call Ready and after a delay, we receive +CPIN: NOT READY and we can't go on.
Why? What does this message mean?
Thank you

 

[ckshivaram]

this tells that the SIM in the modem has been detected properly and its ready to work i.e. accept AT commands........

---------- Post added at 20:07 ---------- Previous post was at 20:06 ----------

some times SIM takes time to get registered... it causes some delay.. that should not be a problem..

 

[lor3nzo]

...but the sim doesn't com back ready no more.
This is the case:

RDY
+CFUN: 1
+CPIN: READY
Call Ready
(few seconds of delay)
+CPIN: NOT READY

and the modem remains in this state

 

[ckshivaram]

use 12V/ 1A power supply for modem.. its due to power supply problem.........

 

[ulrikp]

Hi,

I have the exact same problem. Did you solve this? If yes, please share your solution.

I am using SIM900, and I get this error (only sometimes, and only on some of the modules).

I believe it has to do with power to the SIM card. The attached image is from the documentation. It is suggested to use 100nF for decoupling. It seems that some cases can be overcome with a larger cap, however, even with 100uF, the problem often still appears.

Does anyone have experience with SIMCOM modules or good suggestions here?

BR,
Ulrik

 

[yousafzai82]

I am having exactly the same problem. Sometimes it detects the SIM, most of the times it is not detecting the SIM or it is detecting the SIM but not registering with the network. I am using SIM900d and everything is according to the hd_design_manual recommendation of SIM900d V1.03. Can anyone suggest what maybe the problem?

 

[ulrikp]

SIM PRESENCE error can be several things. Are you sure it's not a mechanical issue with your SIM-holder? You may try to connect the SIM_PRESENCE pin to GND just to check this.

Which message does the SIM900 give when it doesn't register with the network? It would also help if you can upload your schematics.

- - - Updated - - -

By the way, my problem with the "+CPIN: NOT READY" message has been solved. Please see this thread:
https://www.edaboard.com/threads/269175/

 

[GSM Man]

Try changing the capacitor on the SIM Vcc line to .22uF and see if that fixes the problem.