BG95-M3 not registering (CEREG 2 or 4, with COPS manual mode w. automatic fallback) - Same config works on BG95-M2

Hello,

we are using BG95-M2 and BG95-M3 LPWAN modules in IoT setups. The following configuration is working nicely on the M2. However, on the M3 we end up in an endless registration process (CEREG 4,2 (Not registered, but searching) or CEREG 4,4 (Unknown)).

The configuration after boot:
Module successfully started from PSM via PWRKEY.
TX: ATQ0
RX (-1):

TX: ATV1
RX (-1):

TX: ATE1
RX (-1):

TX: AT&D2
RX (-1):

TX: AT+CFUN=1
RX (-1):

TX: AT+CMEE=1
RX (-1):

TX: AT+CREG=0
RX (-1):

TX: AT+CEREG=0
RX (-1):

TX: AT+CPSMS=1,“11011111”,“00100101”
RX (-1):

TX: AT&W
RX (-1):

TX: AT+QCFG=“servicedomain”?
RX (-2):

TX: AT+QCFG=“servicedomain”=1,1
RX (-2):

TX: AT+QSCLK=0
RX (-1):

TX: AT+COPS=4,2,“26202”,8
RX (-1):

TX: AT+QCFG=“nwscanmode”,0,1
RX (-1):

TX: AT+QCFG=“nwscanseq”,00,1
RX (-1):

TX: AT+QCFG=“nb1/bandprior”,1403011C08050C0D12131902041F4247484955
RX (-1):

TX: AT+QCFG=“band”,0x03,0x0000000000000000080080,0x0000000000000000080000,1
RX (-1):

TX: AT+QCFG=“iotopmode”,2,1
RX (-1):

TX: AT+QCFG=“psm/urc”,1
RX (-1):

TX: AT+QGPSCFG=“outport”,uartnmea
RX (-1):

TX: AT+QGPSCFG=“gnssconfig”,3
RX (-1):

TX: AT+QGPSCFG=“gpsnmeatype”,4
RX (-1):

TX: AT+QGPSCFG=“galileonmeatype”,1
RX (-1):

TX: AT+QGPSCFG=“autogps”,0
RX (-1):

TX: AT+QGPSCFG=“priority”,0,1
RX (-1):

TX: AT+QGPSCFG=“xtrafilesize”,7
RX (-1):

TX: AT+QGPSCFG=“xtra_apn”,0,“lpwa.vodafone.com
RX (-1): TX: AT+QGPSXTRA=1

CEREG 4,4 endless loop follows (tested for 3 minutes).

The hardware setup uses a single band antenna on band 20 only - this is why we are configuring mainly band 20.

Why is the M3 ending up in this state?
When i force to connect on GSM (nwscanmode 1 - GSM only), a connection can be established (also working with the same antenna). Switching back to CAT-M priority (nwscanmode 0 with the nwscanseq above), the LTE-M connection works, but only once or twice. The module then goes back to the CEREG 4,4 state.

Thank you for your help!

Hi

Does this SIM support CATM?

Hi

Yes, CATM, Nb-IoT, 2G supported

is this question was resolved? i have one bg95-m3 that is not connecting on 2G also.

my ISP only supports 2G and after i configured the module to “GSM” only, its not registering by AT+CREG (it’s returning 0 or 3)

Hi @Wesley_Brianez

You can check rejection via command:

We are facing similar problem of endless waiting for registation.
We solved it setting the APN already in the initialization phase, instead of waiting for registration to complete.
Seems like that registration can complete only if at least the first context ID is configured (I would not consider the xtra APN).
Can’t say it is the same issue, but may be worth to give it a try