Ok, found it, module issue. We got a new module and that is working fine.

Ok, found it, module issue. We got a new module and that is working fine.

Hi,

We have the SIMCOM 7000E evaluation board but somehow cannot always connect to the NB-IOT network. We also have several uBlox modules on the same location and these are always connecting, so the signal should not be the problem i guess.

The tested output is below:
ATZ
OK
AT+CFUN=0
+CPIN: NOT READY
OK
AT+CNMP=38
OK
AT+CMNB=2
OK
AT+NBSC=0
OK
AT+CBANDCFG=“NB-IOT”,8
OK
AT+CFUN=1
OK
+CPIN: READY
SMS Ready
AT+CREG=1
OK
AT+COPS=1,2,“20416”,9
OK
+CREG: 3
+CREG: 2
AT+COPS?
+COPS: 0,2,“20416”,0 //Connected to the GSM network
OK
AT+CREG?
+CREG: 1,2
OK
AT+CGREG?
+CGREG: 0,5
OK
AT+CGATT?
+CGATT: 1
OK
AT+CPSI?
+CPSI: GSM,Online,204-16,0x0405,13253,858 DCS 1800,-82,0,29-29
OK

As shown in the last line we somehow always connect to the GSM network. Last Monday we were able to the NB-IOT network connect twice, but it is is not clear why, the log of Monday below:
ATZ
OK
AT+CFUN=0
+CPIN: NOT READY
OK
AT+CNMP=38
OK
AT+CMNB=2
OK
AT+NBSC=0
OK
AT+CBANDCFG=“NB-IOT”,8
OK
AT+CFUN=1
OK
+CPIN: READY
SMS Ready
AT+CREG=1
OK
AT+COPS=1,2,“20416”
OK
+CREG: 0
+CREG: 3
AT+COPS=1,2,“20416”,9
OK
AT+CGREG?
+CGREG: 0,5
OK
AT+COPS?
+COPS: 1,2,“20416”,9 //Connected to the NB-IOT network
OK
AT+CGATT?
+CGATT: 1
AT+CGPADDR
+CGPADDR: 1,10.128.0.134 //We got an IP address

Has anybody seen the same behavior before or has a clue on how to check/fix what could be wrong?