Problem to connect internet via gprs modem (wavecom & sim908)

[a.hojjatpanah]

hi there
i have used this at+commands and my problem is error after the "at+cstt" atcommand right at * step

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fputs("ATZ",COM_908); 
fputs("ATE0",COM_908);
fputs("AT+CSCLK=0",COM_908);
delay_ms(2000);
fputs("AT+CREG=0",COM_908);
delay_ms(2000);
fputs("AT+CGACT=1",COM_908);
delay_ms(3000);
fputs("AT+CGATT=1",COM_908);
delay_ms(3000);
fputs("AT+CIPMUX=0",COM_908);
 fputs("AT+CSQ",COM_908);---------> +CSQ: 26,0
fputs("AT+CPIN?",COM_908);--------> +CPIN: READY , OK
 fputs("AT+CREG?",COM_908);--------> +CREG: 0,1 , OK
fputs("AT+CGATT?",COM_908);-----------> +CGATT: 1 , OK
fputs("AT+CIPMUX?",COM_908);--------> +CIPMUX: 0, OK
fputs("AT+CSTT=\"mtnirancell\"",COM_908);-----------> *
fputs("AT+CIICR",COM_908);
fputs("AT+CIFSR",COM_908);
fputs("AT+CIPSTART=\"TCP\",\"www.google.com\",\"80\"",COM_908);

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[FvM]

AT+CSTT may require a dummy username and password along with the APN name. More likely it's a general problem with GPRS service.

See this previous thread how to get extended error messages https://www.edaboard.com/threads/321422/

 

[a.hojjatpanah]

hi dear Fvm
i read the thread that you said but my problem isnt +creg:3 and my +cgatt=1. and my apn have not any username or password. should i put at+creg=1 or 0? and my problem is still alive!

 

[FvM]

If you want to enable unsolicited registration messages or not is a matter of your application design. It only makes sense if you are monitoring modem responses in the background, otherwise the messages are probabably disturbing.

My suggesteion was however about enabling extended error messages with AT+CMEE to know why CSTT command is failing.

 

[kgshankar1980]

1. At first place, pls check AT+CREG=0,1...Until you get this on turning ON the module, pls do not execute the other commands.
2. After the step 1 execute all the other commands.
3. In your code, AT+CSTT command is wrong. If you have only APN and not the username / password then you have to send the AT command in the below format.
AT+CSTT = "mtnirancell",,<ENTER>

If no username and password, still the AT command cannot be executed only APN without that 2 comma's.

 

[a.hojjatpanah]

hi kgshankar
i had used AT+CSTT = "mtnirancell",,<ENTER> but it is returning "operation not allowed" yet!