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Jun 13, 2011
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when I hit CTRL+Z to transmit SMS, then CME ERROR 512 came up. I've read the ERROR description, it says that CME ERROR 512 is "user abort".
GSM Equipment error codes explained
anyone knows how to get AT+CMGS works back?

try using 0x0d and 0x0a ( ENTER ) button of the keyboard,,

Also check at+CSQ? and see if you get the result anything other than 99,99... if you get 99,99 then your modem is not getting any signal fron the network...

thanks for the quick reply

+CSQ: 19,0

try using 0x0d and 0x0a ( ENTER ) button of the keyboard,,
what did you mean exactly?
when I write AT+CMGS="mobile no" then I hit enter, it gives me ">" and if I hit enter again, it gives me ">" on the second line. but when I hit CTRL+Z, then the error came out.

according to this reference **broken link removed**, error 512 means "manufacturer specific".
But I still don't get it what should I do to fix this.

---------- Post added at 17:45 ---------- Previous post was at 17:42 ----------

For additional information, before I tried several GPRS AT Commands to open web page, everything was fine, I were able to send sms with AT+CMGS, but now the error came.

---------- Post added at 17:49 ---------- Previous post was at 17:45 ----------

I also tried to reset factory the modem using AT+WRST and AT&F, but it seems nothing change to the configuration, it still the same configuration as before and still got the error when I send SMS.

I use ULTIMO 24 + TCP GSM/GPRS modem sir.
The AT Commands is compatible with wavecom modem

I can't make a call and receive call, also I can't send and receive SMS.
when I call the modem, it seems the SIM card is not active, i can't make a call to it.
when I send SMS to the modem, the SMS is pending.

How can I flash the software?
Is there any specific AT Commands to do it, or I should contact the customer service?
sorry for the question, I never done it before and Mr. Google couldn't gives me the answer.
thank you.

I think I've found the problem, but have not resolve it yet. I found that the CGATT(attach to GPRS) value is always 1 when the modem is ON, but when I detach "AT+CGATT=0" the indicator of modem is then always freezing (the normal is blinking). I'm sure that because of CGATT=1 then the error came out.

I found the description about CMS ERROR 512 from here CMS ERROR 512
CMS ERROR: 512 indicate 'MM establishment failure'.
This error occurs when you try to send a message and the module is receiving another one at the same time. This causes a collision in the message transfer protocol resulting in failure in sending the SMS and hence, +CMS ERROR: 512.

I still find the way to solve this issue (to detach from GPRS connection with the right way), if anyone has the similar experienced like me now, please guide me to solve it. thanks.

Hi fiolin!
The modem was taken care by the customer service, I don't know exactly what they were doing to my modem. But they said, there is something wrong with the modem.

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