I’m able to accept calls, make outgoing calls, even download web pages via gprs – but after 1-5 minutes I get kicked off the network with bad registration (CREG 3). Once I restart the module I can do it all over agian.
I’m using the SFE “GM862 Evaluation Board - USB” with a bench power supply at 5V (which can source 5A). I can see the module utilize anywhere from .7-1.2A+ on the current readout.
After I lose registration, if I issue AT+CPIN? (for sim presence checking) it returns “SIM Failure”.
My signal strength is always “4 bars” and COPS always returns Cingular as my “current” provider (even after CREG 0,3).
The SIM card always works in the phone it came with – over long periods of time.
I tried a different location (hopefully a different cell tower) – same problem.
I’ve loaded the latest firmware (07.03.400, 07.03.401, and old 7.02.xxx) – same problem
I tried a another module – same problem.
Below are the AT commands I’m using. Why won’t it stay on the network?! :evil: Please help! I’m open to all suggestions!
AT+GMR
07.03.400 // I have tried 07.03.401 also, same problem (and some 7.02.xxx rev that came on the module.
OK
AT+CSQ
+CSQ: 18,0
OK
AT+COPS=?
+COPS: (2,"Cingular",,"310410"),(1,"T-Mobile",,"31026"),,(0-4),(0,2)
OK
AT+cops?
+COPS: 0,0,"Cingular"
OK
AT+BND?
ERROR
AT#BND?
#BND: 1
OK
AT+CP
+CPIN: READY
OK
AT+CREG?
+CREG: 2,1,"466B","14AC"
OK
AT+CSQ
+CSQ: 16,0
OK
+CREG: 1,"466B","0278" // I have it set to display unsolicited creg messages (CREG=2)
AT+CREG?
+CREG: 2,1,"466B","0278" // 1 means connected....
OK
AT+CSQ // 4 bars signal strength
+CSQ: 17,0
OK
AT#MONI
#MONI: Cingular BSIC:67 RxQual:0 LAC:466B Id:0278 ARFCN:741 PWR:-76dbm TA:0
OK
AT#MONI
#MONI: Cingular BSIC:67 RxQual:0 LAC:466B Id:0278 ARFCN:741 PWR:-76dbm TA:0
OK
AT#MONI
#MONI: Cingular BSIC:67 RxQual:0 LAC:466B Id:0278 ARFCN:741 PWR:-75dbm TA:0
OK // moved the antenna over, even better signal strenght
AT+CSQ
+CSQ: 19,0
OK
#QSS: 0 // displays unsolicited SIM card status (QSS=1)
+CREG: 3 // THE PROBLEM!!! -- REGISTRATION NOT ALLOWED NOW?!
at+creg?
+CREG: 2,3
OK
at+cops=?
+COPS: (2,"Cingular",,"310410"),(1,"T-Mobile",,"31026"),,(0-4),(0,2) // Its on AT&T/Cingular and 2 means "current"
OK
at+csq
+CSQ: 18,0 // signal is still rated full "4 bars"
OK
at#moni
#MONI: Cingular BSIC:67 RxQual:0 LAC:466B Id:0278 ARFCN:741 PWR:-76dbm TA:6
at+cmee=2 // display verbose error message
OK
at+cpin? // sim crapped out?
+CME ERROR: SIM failure
at+cfun=4 // disable radio and SIM
OK
at+cfun=1 // re-enabled radio and SIM
OK
#QSS: 1 // displays unsolicited SIM card status (QSS=1)
+CREG: 1,"466B","0278" // unsolicited message: 1 --means registered sucessfully agian.
at+csq // 4 bars
+CSQ: 18,0
OK
#QSS: 0
+CREG: 3 // 2 minutes later... disconnected, bad registration!
at+cops=?
+COPS: (2,"Cingular",,"310410"),(1,"T-Mobile",,"31026"),,(0-4),(0,2)
OK
at+cpin?
+CME ERROR: SIM failure