BG96_Vietnam_Viettel_Don't know whether I have connected to network

Hi there,

Im from Vietnam. Our operator is Viettel. Im testing NB-IoT BG96, revision: BG96MAR02A07M1G, and trying to know whether I have connected to NB-IoT network.
Below is my AT command script.
I found result is weird that while “AT+CEREG” returns “+CEREG: 0,1” means registered-home network, “AT+CREG?” returns “+CREG: 0,3” meas registration denied and “AT+CGREG? returns +CGREG: 0,4”, means unknown.
I also continously check the signal with “AT+QCSQ” and “AT+CSQ”, and it always returns values.
Those things make me so confused. Plz help.

06:47:52.558 -> AT+CIND?
06:47:52.592 -> +CIND: 0,3,1,1,0,0,1,0
06:47:52.592 ->
06:47:52.592 -> OK
06:48:02.504 -> AT+COPS?
06:48:02.504 -> +COPS: 0,0,“Viettel Viettel”,9
06:48:02.538 ->
06:48:02.538 -> OK
06:48:10.598 -> AT+CSQ
06:48:10.632 -> +CSQ: 18,99
06:48:10.632 ->
06:48:10.632 -> OK
06:48:14.989 -> AT+QCSQ
06:48:14.989 -> +QCSQ: “CAT-NB1”,-77,-87,89,-15
06:48:15.023 ->
06:48:15.023 -> OK
06:48:22.914 -> AT+CEREG?
06:48:22.914 -> +CEREG: 0,1
06:48:22.948 ->
06:48:22.948 -> OK
06:48:45.234 -> AT+CREG?
06:48:45.269 -> +CREG: 0,3
06:48:45.269 ->
06:48:45.269 -> OK
06:50:11.835 -> AT+CGACT?
06:50:11.868 -> +CGACT: 1,1
06:50:11.868 ->
06:50:11.868 -> OK
06:50:18.196 -> AT+QNWINFO
06:50:18.230 -> +QNWINFO: “CAT-NB1”,“45204”,“LTE BAND 3”,1791
06:50:18.263 ->
06:50:18.263 -> OK
06:50:24.711 -> AT+CGCONTRDP
06:50:24.745 -> +CGCONTRDP: 1,5,nbiot,9.93.13.227,
06:50:24.780 ->
06:50:24.780 -> OK
06:51:05.578 -> AT+CGATT?
06:51:05.613 -> +CGATT: 1
06:51:05.613 ->
06:51:05.613 -> OK
06:51:28.677 -> AT+CGREG?
06:51:28.711 -> +CGREG: 0,4
06:51:28.711 ->
06:51:28.711 -> OK
06:51:28.711 -> OK
06:54:15.335 -> AT+CSQ
06:54:15.335 -> +CSQ: 18,99
06:54:15.370 ->
06:54:15.370 -> OK
06:54:44.866 -> ATE1
06:54:44.866 -> OK
06:55:08.815 -> ATE
06:55:08.815 -> OK
06:55:12.281 -> AT+CSQ
06:55:12.316 -> +CSQ: 18,99
06:55:12.316 ->
06:55:12.316 -> OK
06:58:46.716 -> AT+CPAS
06:58:46.751 -> +CPAS: 0
06:58:46.751 ->
06:58:46.751 -> OK
07:02:17.000 -> AT+CGACT?
07:02:17.034 -> +CGACT: 1,1
07:02:17.034 ->
07:02:17.034 -> OK
07:02:21.530 -> AT+CGPADDR=?
07:02:21.530 -> +CGPADDR: (1)
07:02:21.530 ->
07:02:21.564 -> OK
07:02:29.022 -> AT+QGDCNT?
07:02:29.057 -> +QGDCNT: 0,0
07:02:29.057 ->
07:02:29.057 -> OK
07:02:33.526 -> AT+QAUGDCNT?
07:02:33.560 -> +QAUGDCNT: 0
07:02:33.560 ->
07:02:33.560 -> OK
07:03:19.796 -> AT+CGDCONT?
07:03:19.796 -> +CGDCONT: 1,“IPV4V6”,"",“0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”,0,0,0,0
07:03:19.865 ->
07:03:19.865 -> OK
07:04:04.876 -> AT+QCSQ
07:04:04.876 -> +QCSQ: “CAT-NB1”,-72,-88,102,-12
07:04:04.944 ->
07:04:04.944 -> OK

Could someone help me in this situation?.
I’ld be very grateful for your help. Thank you.

Hello,
I am facing a similar issue, have you found a workaround?

Hi Vitom,

I have found out.
The command “AT+CEREG?” -> +CEREG: 0,1 means it 's already registered to the Packet Switch Domain, but still not access to the internet yet.

I have to read BG96’s at command tcp/ip, activate PDP context then configure DNS add, after that it works.

I hope my answer can help you.

I was moving towards that direction as well, good to know that’s the right path, thanks!

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