Hi,
I have an issue with the nRF9160 getting stuck in CEREG response 4 (Unknown). When I look into the full CEREG status, I can see that the EMM reject cause is 15 (Cause #15 – No suitable cells in tracking area). This will continue forever as the device seems to have no method of finding a different cell to connect to.
I know that there are cells in my area that I can in fact connect to as a power on reset will find a connectable network in under 30 seconds with a CESQ RSRP of around 20-26. I would like to know is there a method of purging the known cell tower from the modem so that it will not attempt to reconnect with the tower that is sending the rejection? My application swaps between LTE and GPS so the modem characteristics (CFUN, XSYSTEMMODE, MAGPIO, CGDCONT) are being reset between each swap but the previously connected cell is what the device locks onto once LTE is active again.
[2020-02-24 16:59:26] Socket status: 5:11, No more processes
[2020-02-24 16:59:26] Sending AT command: AT+CEREG?
[2020-02-24 16:59:26] Modem response: +CEREG: 1,4
[2020-02-24 16:59:26] OK
[2020-02-24 16:59:26]
[2020-02-24 16:59:26] Socket status: 18:11, No more processes
[2020-02-24 16:59:26] Failed to receive "+CEREG: 1,5" from modem
[2020-02-24 16:59:26] Requesting Advanced CEREG
[2020-02-24 16:59:26] Radio Scheduler had error with task: 3:-3
[2020-02-24 16:59:27] Sending AT command: AT+CEREG=5
[2020-02-24 16:59:27] Modem response: OK
[2020-02-24 16:59:27]
[2020-02-24 16:59:27] Socket status: 5:11, No more processes
[2020-02-24 16:59:27] Sending AT command: AT+CEREG?
[2020-02-24 16:59:27] Modem response: +CEREG: 5,4,"A45D","07CBF70B",9,0,15,"11100000","11100000"
[2020-02-24 16:59:27] OK
[2020-02-24 16:59:27]
[2020-02-24 16:59:27] Socket status: 65:11, No more processes
[2020-02-24 16:59:36] Sending AT command: AT+CEREG=1
[2020-02-24 16:59:36] Modem response: OK
[2020-02-24 16:59:36]
[2020-02-24 16:59:36] Socket status: 5:11, No more processes
[2020-02-24 16:59:36] Sending AT command: AT+CEREG?
[2020-02-24 16:59:36] Modem response: +CEREG: 1,4
[2020-02-24 16:59:36] OK
[2020-02-24 16:59:36]
[2020-02-24 16:59:36] Socket status: 18:11, No more processes
[2020-02-24 16:59:36] Failed to receive "+CEREG: 1,5" from modem
[2020-02-24 16:59:36] Requesting Advanced CEREG
[2020-02-24 16:59:36] Radio Scheduler had error with task: 3:-3
[2020-02-24 16:59:37] Sending AT command: AT+CEREG=5
[2020-02-24 16:59:37] Modem response: OK
[2020-02-24 16:59:37]
[2020-02-24 16:59:37] Socket status: 5:11, No more processes
[2020-02-24 16:59:37] Sending AT command: AT+CEREG?
[2020-02-24 16:59:37] Modem response: +CEREG: 5,4,"A45D","07CBF70B",9,0,15,"11100000","11100000"
[2020-02-24 16:59:37] OK
[2020-02-24 16:59:37]
[2020-02-24 16:59:37] Socket status: 65:11, No more processes
[2020-02-24 16:59:44] Sending AT command: AT%XVBAT
[2020-02-24 16:59:44] Modem response: %XVBAT: 4395
[2020-02-24 16:59:44] OK
[2020-02-24 16:59:44]
[2020-02-24 16:59:44] Socket status: 19:11, No more processes
[2020-02-24 16:59:44] iVBatt: 4395
[2020-02-24 16:59:46] Sending AT command: AT+CEREG=1
[2020-02-24 16:59:46] Modem response: OK
[2020-02-24 16:59:46]
[2020-02-24 16:59:46] Socket status: 5:11, No more processes
[2020-02-24 16:59:46] Sending AT command: AT+CEREG?
[2020-02-24 16:59:46] Modem response: +CEREG: 1,4
[2020-02-24 16:59:46] OK
[2020-02-24 16:59:46]
[2020-02-24 16:59:46] Socket status: 18:11, No more processes
[2020-02-24 16:59:46] Failed to receive "+CEREG: 1,5" from modem
[2020-02-24 16:59:46] Requesting Advanced CEREG
[2020-02-24 16:59:46] Radio Scheduler had error with task: 3:-3
[2020-02-24 16:59:47] Sending AT command: AT+CEREG=5
[2020-02-24 16:59:47] Modem response: OK
[2020-02-24 16:59:47]
[2020-02-24 16:59:47] Socket status: 5:11, No more processes
[2020-02-24 16:59:47] Sending AT command: AT+CEREG?
[2020-02-24 16:59:47] Modem response: +CEREG: 5,4,"A45D","07CBF70B",9,0,15,"11100000","11100000"
[2020-02-24 16:59:47] OK
[2020-02-24 16:59:47]
[2020-02-24 16:59:47] Socket status: 65:11, No more processes
[2020-02-24 16:59:56] Sending AT command: AT+CEREG=1
[2020-02-24 16:59:56] Modem response: OK
[2020-02-24 16:59:56]
[2020-02-24 16:59:56] Socket status: 5:11, No more processes
[2020-02-24 16:59:56] Sending AT command: AT+CEREG?
[2020-02-24 16:59:56] Modem response: +CEREG: 1,4
[2020-02-24 16:59:56] OK
[2020-02-24 16:59:56]
[2020-02-24 16:59:56] Socket status: 18:11, No more processes
[2020-02-24 16:59:56] Failed to receive "+CEREG: 1,5" from modem
[2020-02-24 16:59:56] Requesting Advanced CEREG
[2020-02-24 16:59:56] Radio Scheduler had error with task: 3:-3
[2020-02-24 16:59:57] Sending AT command: AT+CEREG=5
[2020-02-24 16:59:57] Modem response: OK
[2020-02-24 16:59:57]
[2020-02-24 16:59:57] Socket status: 5:11, No more processes
[2020-02-24 16:59:57] Sending AT command: AT+CEREG?
[2020-02-24 16:59:57] Modem response: +CEREG: 5,4,"A45D","07CBF70B",9,0,15,"11100000","11100000"
[2020-02-24 16:59:57] OK
[2020-02-24 16:59:57]
[2020-02-24 16:59:57] Socket status: 65:11, No more processes
[2020-02-24 17:00:01] Reset variables
[2020-02-24 17:00:01] Changing uControl_Word state
[2020-02-24 17:00:01] IDLE state
[2020-02-24 17:00:01] Event NBIOT_COMPLETE Triggered!
[2020-02-24 17:00:01] Changing uControl_Word state
[2020-02-24 17:00:01] GPS state
[2020-02-24 17:00:01] Sending AT command: AT+CFUN=4
[2020-02-24 17:00:01] Modem response: OK
[2020-02-24 17:00:01]
[2020-02-24 17:00:01] Socket status: 5:11, No more processes
[2020-02-24 17:00:01] Sending AT command: AT%XSYSTEMMODE=0,0,1,0
[2020-02-24 17:00:01] Modem response: OK
[2020-02-24 17:00:01]
[2020-02-24 17:00:01] Socket status: 5:11, No more processes
[2020-02-24 17:00:01] Sending AT command: AT%XMAGPIO=1,1,1,1,7,1574,1577
[2020-02-24 17:00:01] Modem response: OK
[2020-02-24 17:00:01]
[2020-02-24 17:00:01] Socket status: 5:11, No more processes
[2020-02-24 17:00:01] Sending AT command: AT+CFUN=1
[2020-02-24 17:00:01] Modem response: OK
[2020-02-24 17:00:01]
[2020-02-24 17:00:01] Socket status: 5:11, No more processes
[2020-02-24 17:00:01] Socket created
[2020-02-24 17:00:01] Socket ID 1232491587
[2020-02-24 17:00:01] Fix retry err: 0:11 No more processes
[2020-02-24 17:00:01] Fix interval err: 0:11 No more processes
[2020-02-24 17:00:01] nmea mask err: 0:11 No more processes
[2020-02-24 17:00:01] GPS start err: 0:11 No more processes
[2020-02-24 17:00:01] Changing uControl_Word state
[2020-02-24 17:00:01] GPS state
[2020-02-24 17:00:01] Tracking: 2 Using: 0 Unhealthy: 0
[2020-02-24 17:00:01] Scanning [|]
[2020-02-24 17:00:01] Seconds Since GPS Search Start 0
[2020-02-24 17:00:01]
[2020-02-24 17:00:02] Tracking: 0 Using: 0 Unhealthy: 0
[2020-02-24 17:00:02] Scanning [/]
[2020-02-24 17:00:02] Seconds Since GPS Search Start 1
[2020-02-24 17:00:02]
[2020-02-24 17:00:03] Tracking: 0 Using: 0 Unhealthy: 0
[2020-02-24 17:00:03] Scanning [-]
[2020-02-24 17:00:03] Seconds Since GPS Search Start 2
[2020-02-24 17:00:03]
...................
[2020-02-24 17:01:53]
[2020-02-24 17:01:54] Tracking: 0 Using: 0 Unhealthy: 0
[2020-02-24 17:01:54] Scanning [|]
[2020-02-24 17:01:54] Seconds Since GPS Search Start 112
[2020-02-24 17:01:54]
[2020-02-24 17:01:55] Tracking: 0 Using: 0 Unhealthy: 0
[2020-02-24 17:01:55] Scanning [/]
[2020-02-24 17:01:55] Seconds Since GPS Search Start 113
[2020-02-24 17:01:55]
[2020-02-24 17:01:56] Interrupt tripped!
[2020-02-24 17:01:56] Tracking: 0 Using: 0 Unhealthy: 0
[2020-02-24 17:01:56] Scanning [-]
[2020-02-24 17:01:56] Reading Status Register
[2020-02-24 17:01:56] SPI Interrupt: 0x21
[2020-02-24 17:01:56] Deactivate
[2020-02-24 17:01:56] Disabling UART
[2020-02-24 17:01:56] Disabling SPI
[2020-02-24 17:01:56] Seconds Since GPS Search Start 114
[2020-02-24 17:01:56]
[2020-02-24 17:01:57] Event DEACTIVATE Triggered!
[2020-02-24 17:01:57] Changing uControl_Word state
[2020-02-24 17:01:57] PRESLEEP state
[2020-02-24 17:01:57] Halting GPS Scan, INT1 shutdown
[2020-02-24 17:01:57] Shutting down GPS
[2020-02-24 17:01:57] Enabling Sleep mode, switching to NB-IoT
[2020-02-24 17:01:57] Sending AT command: AT+CFUN=4
[2020-02-24 17:01:57] Modem response: OK
[2020-02-24 17:01:57]
[2020-02-24 17:01:57] Socket status: 5:11, No more processes
[2020-02-24 17:01:57] Sending AT command: AT%XSYSTEMMODE=0,1,0,0
[2020-02-24 17:01:57] Modem response: OK
[2020-02-24 17:01:57]
[2020-02-24 17:01:57] Socket status: 5:11, No more processes
[2020-02-24 17:01:57] Sending AT command: AT%XMAGPIO=1,1,1,1,5,791,849
[2020-02-24 17:01:57] Modem response: OK
[2020-02-24 17:01:57]
[2020-02-24 17:01:57] Socket status: 5:11, No more processes
[2020-02-24 17:01:57] Sending AT command: AT+CGDCONT=0,"IP","ep.inetd.gdsp"
[2020-02-24 17:01:58] Modem response: OK
[2020-02-24 17:01:58]
[2020-02-24 17:01:58] Socket status: 5:11, No more processes
[2020-02-24 17:01:58] Sending AT command: AT+CFUN=1
[2020-02-24 17:01:58] Modem response: OK
[2020-02-24 17:01:58]
[2020-02-24 17:01:58] Socket status: 5:11, No more processes
[2020-02-24 17:01:58] Enabling Sleep mode
[2020-02-24 17:01:58] Changing uControl_Word state
[2020-02-24 17:01:58] IDLE state
[2020-02-24 17:01:59] Sending AT command: AT+CEREG=1
[2020-02-24 17:01:59] Modem response: OK
[2020-02-24 17:01:59]
[2020-02-24 17:01:59] Socket status: 5:11, No more processes
[2020-02-24 17:01:59] Sending AT command: AT+CEREG?
[2020-02-24 17:01:59] Modem response: +CEREG: 1,4
[2020-02-24 17:01:59] OK
[2020-02-24 17:01:59]
[2020-02-24 17:01:59] Socket status: 18:11, No more processes
[2020-02-24 17:01:59] Failed to receive "+CEREG: 1,5" from modem
[2020-02-24 17:01:59] Requesting Advanced CEREG
[2020-02-24 17:01:59] Radio Scheduler had error with task: 3:-3
[2020-02-24 17:01:59] Sending AT command: AT+CEREG=5
[2020-02-24 17:01:59] Modem response: OK
[2020-02-24 17:01:59]
[2020-02-24 17:01:59] Socket status: 5:11, No more processes
[2020-02-24 17:01:59] Sending AT command: AT+CEREG?
[2020-02-24 17:01:59] Modem response: +CEREG: 5,4,"A45D","07CBF70B",9,0,15,"11100000","11100000"
[2020-02-24 17:01:59] OK
[2020-02-24 17:01:59]
[2020-02-24 17:01:59] Socket status: 65:11, No more processes
[2020-02-24 17:02:09] Sending AT command: AT+CEREG=1
[2020-02-24 17:02:09] Modem response: OK
[2020-02-24 17:02:09]
[2020-02-24 17:02:09] Socket status: 5:11, No more processes
[2020-02-24 17:02:09] Sending AT command: AT+CEREG?
[2020-02-24 17:02:09] Modem response: +CEREG: 1,4
[2020-02-24 17:02:09] OK
[2020-02-24 17:02:09]
[2020-02-24 17:02:09] Socket status: 18:11, No more processes
[2020-02-24 17:02:09] Failed to receive "+CEREG: 1,5" from modem
[2020-02-24 17:02:09] Requesting Advanced CEREG
[2020-02-24 17:02:09] Radio Scheduler had error with task: 3:-3
[2020-02-24 17:02:09] Sending AT command: AT+CEREG=5
[2020-02-24 17:02:09] Modem response: OK
[2020-02-24 17:02:09]
[2020-02-24 17:02:09] Socket status: 5:11, No more processes
[2020-02-24 17:02:09] Sending AT command: AT+CEREG?
[2020-02-24 17:02:09] Modem response: +CEREG: 5,4,"A45D","07CBF70B",9,0,15,"11100000","11100000"
[2020-02-24 17:02:09] OK
[2020-02-24 17:02:09]
[2020-02-24 17:02:09] Socket status: 65:11, No more processes
[2020-02-24 17:02:19] Sending AT command: AT+CEREG=1
[2020-02-24 17:02:19] Modem response: OK
[2020-02-24 17:02:19]
[2020-02-24 17:02:19] Socket status: 5:11, No more processes
[2020-02-24 17:02:19] Sending AT command: AT+CEREG?
[2020-02-24 17:02:19] Modem response: +CEREG: 1,4
[2020-02-24 17:02:19] OK
[2020-02-24 17:02:19]
[2020-02-24 17:02:19] Socket status: 18:11, No more processes
[2020-02-24 17:02:19] Failed to receive "+CEREG: 1,5" from modem
[2020-02-24 17:02:19] Requesting Advanced CEREG
[2020-02-24 17:02:19] Radio Scheduler had error with task: 3:-3
[2020-02-24 17:02:19] Sending AT command: AT+CEREG=5
[2020-02-24 17:02:19] Modem response: OK
[2020-02-24 17:02:19]
[2020-02-24 17:02:19] Socket status: 5:11, No more processes
[2020-02-24 17:02:19] Sending AT command: AT+CEREG?
[2020-02-24 17:02:19] Modem response: +CEREG: 5,4,"A45D","07CBF70B",9,0,15,"11100000","11100000"
[2020-02-24 17:02:19] OK
[2020-02-24 17:02:19]
