System mode from ntn to lte doesnt save to non volatile memory

[Geolink_olivier]

Hi! This is a general info post since i have found a temporary fix to it, but whilst trying out ntn, we noticed that when switching from %XSYSTEMMODE: 0,0,1,0,0 to %XSYSTEMMODE: 1,1,1,3,0 CFUN=1 hangs and causes the config to not be saved thus remaining stuck in ntn mode, working with monogoto, we figured the only fix was to run a factory reset then to run the system mode command and CFUN=1 which this time doesnt hang. 

[Geolink_olivier]

I do not have a serial connection to my board, only rtt, and i could not find a sample named serial modem to adapt to rtt thus i cannot try it, this is the sequence of at commands i currently run tho. 

00> [00:01:37.034,149] <inf> ntn_manager: NTN: AT> AT%XSYSTEMMODE=0,0,0,0,1 [SYSMODE NTN]
\
00> [00:01:37.041,320] <inf> ntn_manager: NTN: AT< OK [SYSMODE NTN] dt=7ms
\
00> [00:01:37.041,412] <inf> ntn_manager: NTN: AT> AT%XBANDLOCK=2,,"23,255,256" [BANDLOCK]
\
00> [00:01:37.042,175] <inf> ntn_manager: NTN: AT< OK [BANDLOCK] dt=1ms
\
00> [00:01:37.042,236] <inf> ntn_manager: NTN: AT> AT%LOCATION=1 [LOCATION subscribe]
\
00> [00:01:37.042,999] <inf> ntn_manager: NTN: AT< OK [LOCATION subscribe] dt=0ms
\
00> [00:01:37.050,598] <inf> ntn_manager: NTN: modem location set: lat=--.------ lon=--.------ alt=146.5 acc=0 val=0 (infinite)
\
00> [00:01:37.050,659] <inf> ntn_manager: NTN: AT> AT+CGDCONT=0,"IP","data.mono" [CGDCONT NTN IP]
\
00> [00:01:37.051,361] <inf> ntn_manager: NTN: AT< OK [CGDCONT NTN IP] dt=1ms
\
00> [00:01:37.051,422] <inf> ntn_manager: NTN: AT> AT+CEREG=5 [CEREG]
\
00> [00:01:37.051,971] <inf> ntn_manager: NTN: AT< OK [CEREG] dt=0ms
\
00> [00:01:37.052,001] <inf> ntn_manager: NTN: AT> AT+CNEC=24 [CNEC]
\
00> [00:01:37.052,581] <inf> ntn_manager: NTN: AT< OK [CNEC] dt=1ms
\
00> [00:01:37.052,642] <inf> ntn_manager: NTN: AT> AT+CSCON=3 [CSCON]
\
00> [00:01:37.053,192] <inf> ntn_manager: NTN: AT< OK [CSCON] dt=1ms
\
00> [00:01:37.053,253] <inf> ntn_manager: NTN: AT> AT%MDMEV=2 [MDMEV]
\
00> [00:01:37.053,802] <inf> ntn_manager: NTN: AT< OK [MDMEV] dt=0ms
\
00> [00:01:37.053,833] <inf> ntn_manager: NTN: Skylo - sending AT%SKYLO=0,1 and AT%SKYLO=1,1 
\
00> [00:01:37.053,894] <inf> ntn_manager: NTN: AT> AT%SKYLO=0,1 [SKYLO generic]
\
00> [00:01:37.054,687] <inf> ntn_manager: NTN: AT< OK [SKYLO generic] dt=1ms
\
00> [00:01:37.054,748] <inf> ntn_manager: NTN: AT> AT%SKYLO=1,1 [SKYLO MO-device]
\
00> [00:01:37.055,572] <inf> ntn_manager: NTN: AT< OK [SKYLO MO-device] dt=1ms
\
00> [00:01:37.055,572] <inf> ntn_manager: NTN: Skylo AT commands accepted (OK)
\
00> [00:01:37.055,664] <inf> ntn_manager: NTN: AT> AT+CPSMS=1,"","","10100101","10000011" [CPSMS NTN]
\
00> [00:01:37.056,243] <inf> ntn_manager: NTN: AT< OK [CPSMS NTN] dt=1ms
\
00> [00:01:37.056,304] <inf> ntn_manager: NTN: AT> AT+CFUN=1 [CFUN=1]
\
00> [00:01:37.080,505] <inf> ntn_manager: NTN: AT< OK [CFUN=1] dt=24ms

and the next command that hangs is AT+CFUN=0 about 5 minutes later

[Geolink_olivier]

Is there a modem trace option to use rtt instead of serial?

[Øyvind]

Hello, apologies for the late reply, I have been out of office the last days.

Geolink_olivier said:

Is there a modem trace option to use rtt instead of serial?

Yes, we do have support for modem tracing over RTT.

Geolink_olivier said:

i could not find a sample named serial modem to adapt to rtt

There should be support for this in the serial modem application. 

Then in JLink RTT Viewer use Logging -> Start Data logging.

Kind regards,
Øyvind

[Geolink_olivier]

issue is currently being resolved in private ticket, possible firmware issue, TBD.