nRF9160 don't see the NB-IoT networks

RE: nRF9160 don't see the NB-IoT networks

Vladimir Aparin — Thu, 01 Aug 2019 14:19:15 GMT

After i configured bands, Nb-IoT mode, powered the modem and start the registration all works now:

***** Booting Zephyr OS v1.14.99-ncs2 *****
The AT host sample started
AT+CFUN?
+CFUN: 4
OK
AT+CFUN=1
OK
AT+CFUN?
+CFUN: 1
OK
AT+CGSN=1
+CGSN: "352656100031668"
OK
AT+CGMI
Nordic Semiconductor ASA
OK
AT+CGMM
nRF9160-SICA
OK
AT+CGMR
mfw_nrf9160_1.0.0
OK
AT+CEMODE?
+CEMODE: 0
OK
AT%XCBAND=?
%XCBAND: (3,8,20)
OK
AT+CMEE?
+CMEE: 0
OK
AT+CMEE=1
OK
AT+CNEC?
+CNEC: 0
OK
AT+CNEC=24
OK
AT+CGEREP?
+CGEREP: 0,0
OK
AT+CGDCONT?
OK
AT+CGACT?
OK
AT+CGEREP=1
OK
AT+CIND=1,1,1
OK
AT+CEREG=2
OK
AT+CEREG?
+CEREG: 2,4,"FFFE","FFFFFFFF",9
OK
AT%CESQ=1
OK
AT+CESQ
+CESQ: 99,99,255,255,255,255
OK
AT%XSIM=1
OK
AT%XSIM?
%XSIM: 1
OK
AT+CPIN?
+CPIN: READY
OK
AT+CPINR="SIM PIN"
+CPINR: "SIM PIN",3
OK
AT+CIMI
250011791500068
OK
%CESQ: 34,1
+CEREG: 2,"4B6A","030E3808",9
+CGEV: ME PDN ACT 0
AT+CGDCONT?
+CEREG: 1,"4B6A","030E3808",9
+CIND: "service",1
+CGDCONT: 0,"IPV4V6","iot","10.0.44.178 0000:0000:0000:0000:0000:0002:FC39:9301",0,0
OK
AT+CGACT?
+CGACT: 0,1
OK
+CGEV: IPV6 0
AT+CGDCONT?
+CGDCONT: 0,"IPV4V6","iot","10.0.44.178 2A00:1FA0:2000:8B83:0000:0002:FC39:9301",0,0
OK
AT+CGACT?
+CGACT: 0,1
OK
%CESQ: 39,1
AT+CFUN?
+CFUN: 1
OK
AT+CGSN=1
+CGSN: "352656100031668"
OK
AT+CGMI
Nordic Semiconductor ASA
OK
AT+CGMM
nRF9160-SICA
OK
AT+CGMR
mfw_nrf9160_1.0.0
OK
AT+CEMODE?
+CEMODE: 0
OK
AT%XCBAND=?
%XCBAND: (3,8,20)
OK
AT+CMEE?
+CMEE: 1
OK
AT+CNEC?
+CNEC: 24
OK
AT+CGEREP?
+CGEREP: 1,0
OK
AT+CIND=1,1,1
OK
AT+CEREG=2
OK
AT+CEREG?
+CEREG: 2,1,"4B6A","030E3808",9
OK
AT+COPS=3,2
OK
AT+COPS?
+COPS: 0,2,"25001",9
OK
AT%XCBAND
%XCBAND: 20
OK
AT+CGDCONT?
+CGDCONT: 0,"IPV4V6","iot","10.0.44.178 2A00:1FA0:2000:8B83:0000:0002:FC39:9301",0,0
OK
AT+CGACT?
+CGACT: 0,1
OK
AT%CESQ=1
OK
AT+CESQ
+CESQ: 99,99,255,255,255,39
OK
AT%XSIM=1
OK
AT%XSIM?
%XSIM: 1
OK
AT+CPIN?
+CPIN: READY
OK
AT+CPINR="SIM PIN"
+CPINR: "SIM PIN",3
OK
AT+CIMI
250011791500068
OK

So it's required

AT%XBANDLOCK=1,"10000000000010000100"
AT%XSYSTEMMODE=0,1,0,0
AT+CFUN=1
AT+CEREG=2

RE: nRF9160 don't see the NB-IoT networks

MJD093 — Thu, 01 Aug 2019 13:39:43 GMT

Ok, attachment to a network isn't likely happen that quickly. I have seen the attachment take several minutes in poor reception areas. You need to give the module at least a minute before testing if it has made a connection. It is not necessary to read the status of CFUN, CFUN must be set to 1 in order for the modem to activate but you do not need to read the status of CFUN for the modem to attach. I wouldn't worry too much about band selection, this should be automatic as the device will default to scanning all LTE bands.

An additioanl question, are you testing this inside a building or in the open air, away from structures? From my own personal testing with the pca10090 DK, the reception will be quite low inside a structure, usually lower than -110dBm

RE: nRF9160 don't see the NB-IoT networks

Vladimir Aparin — Thu, 01 Aug 2019 12:45:38 GMT

I see that it's required to read CFUN status and got 1 before works onward.

I configured the bands (B3, B8, B20) but I still see the 0 (unknown) in answer.

***** Booting Zephyr OS v1.14.99-ncs2 *****

The AT host sample started

AT%XCBAND
%XCBAND: 0

OK

AT%XCBAND=?
%XCBAND: (1,2,3,4,5,8,12,13,14,17,18,19,20,25,26,28,66)

OK

AT%XBANDLOCK=1,"10000000000010000100"
OK

AT%XCBAND
%XCBAND: 0

OK


AT%XCBAND=?
%XCBAND: (3,8,20)

OK

AT+CFUN?
+CFUN: 4

OK

AT+CFUN=1
OK

AT+CFUN?
+CFUN: 1

OK

AT+COPS?
+COPS: 0

OK

AT+COPS?
ERROR

AT+COPS?
+COPS: 0

OK

AT+CEREG=2
OK

AT+COPS?
+COPS: 0

OK

AT+CEREG?
+CEREG: 2,2,"FFFE","FFFFFFFF",7

OK

AT+CEREG?
+CEREG: 2,2,"FFFE","FFFFFFFF",7

OK

RE: nRF9160 don't see the NB-IoT networks

Vladimir Aparin — Thu, 01 Aug 2019 12:31:28 GMT

In 5 seconds approximatelly.

See the log about

***** Booting Zephyr OS v1.14.99-ncs2 *****

The AT host sample started

AT+CFUN=1
OK

AT+CEREG?
+CEREG: 0,4,"FFFE","FFFFFFFF",7

OK

AT+CEREG=2
OK

AT+COPS=?
AT+CEREG?

RE: nRF9160 don't see the NB-IoT networks

MJD093 — Thu, 01 Aug 2019 11:39:05 GMT

How long after setting CFUN=1 are you calling COPS=?

At+CEREG? is a better debug command for network attachment as it provides information on eNodeB attachment and the current state of the modem in the attachment process. Could you provide the response of that command?

RE: nRF9160 don't see the NB-IoT networks

Vladimir Aparin — Thu, 01 Aug 2019 11:32:15 GMT

***** Booting Zephyr OS v1.14.99-ncs2 *****

The AT host sample started

AT%XSYSTEMMODE=0,1,0,0
OK

AT+CFUN=1
OK

AT+CEREG=2
OK

AT+COPS=?

RE: nRF9160 don't see the NB-IoT networks

MJD093 — Thu, 01 Aug 2019 11:23:21 GMT

If you updated the modem's firmware recently to the latest version, you must specify what LTE specification you wish to use. Have you remembered to use the AT%XSYSTEMMODE command to set the Modem to NB-IoT mode?

Please describe how you are using the AT Client to access the NB-IoT network. Also provide some UART logs of the at_client commands and responses your device is outputting.