Not responding to AT commands

[Praveen katari]

Hi Team,

i am working on serial LTE modem sample project trying to send at commands through serial lte link monitor, found that device is not responding to at commands after below mentioned sequence.

AT+CFUN=1;

AT+CFUN?

AT+CGATT=0   --> no response for this at command.

after that no  response for the any AT commands.  

Note*: We also observed that for the at command given below. IP address we are getting response as shown below. Because of the below format of IP address we see an ERROR invalid IP address.

>> AT+CGDCONT?\x0D\x0A
<< +CGDCONT: 0,"IPV4V6","cmw500.rohde-schwarz.com","192.168.1.30 FC01:ABAB:CDCD:EFE0:0000:0000:0000:0001",0,0\x0D\x0A

logs are attached.

Fullscreen Issue1.txt Download

2020-05-12T06:14:06.562Z DEBUG modem >> AT\x0D\x0A
2020-05-12T06:14:06.584Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:14:15.597Z DEBUG modem >> AT\x0D\x0A
2020-05-12T06:14:15.624Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:04.011Z DEBUG modem >> AT+CFUN?\x0D\x0A
2020-05-12T06:15:04.034Z DEBUG modem << +CFUN: 0\x0D
2020-05-12T06:15:04.064Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:15.596Z DEBUG modem >> AT+CFUN=1\x0D\x0A
2020-05-12T06:15:15.637Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:18.133Z DEBUG modem >> AT+CFUN=1\x0D\x0A
2020-05-12T06:15:18.138Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.143Z DEBUG modem >> AT+CFUN?\x0D\x0A
2020-05-12T06:15:21.169Z DEBUG modem << +CFUN: 1\x0D
2020-05-12T06:15:21.198Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.201Z DEBUG modem >> AT+CGSN=1\x0D\x0A
2020-05-12T06:15:21.208Z DEBUG modem << +CGSN: "352656100378499"\x0D
2020-05-12T06:15:21.243Z DEBUG modem << \x0A
2020-05-12T06:15:21.244Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.247Z DEBUG modem >> AT+CGMI\x0D\x0A
2020-05-12T06:15:21.253Z DEBUG modem << Nordic Semiconductor ASA\x0D
2020-05-12T06:15:21.282Z DEBUG modem << \x0A
2020-05-12T06:15:21.283Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.287Z DEBUG modem >> AT+CGMM\x0D\x0A
2020-05-12T06:15:21.292Z DEBUG modem << nRF9160-SICA\x0D
2020-05-12T06:15:21.294Z DEBUG modem << \x0A
2020-05-12T06:15:21.295Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.316Z DEBUG modem >> AT+CGMR\x0D\x0A
2020-05-12T06:15:21.341Z DEBUG modem << mfw_nrf9160_1.1.1\x0D\x0A
2020-05-12T06:15:21.342Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.343Z INFO Nordic Semiconductor ASA nRF9160-SICA [mfw_nrf9160_1.1.1] SerNr: 352656100378499
2020-05-12T06:15:21.344Z DEBUG modem >> AT+CEMODE?\x0D\x0A
2020-05-12T06:15:21.372Z DEBUG modem << +CEMODE: 2\x0D\x0A
2020-05-12T06:15:21.374Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.400Z DEBUG modem >> AT%XCBAND=?\x0D\x0A
2020-05-12T06:15:21.425Z DEBUG modem << %XCBAND: (1,2,3,4,5,8,12,13,14,17,18,19,20,25,26,28,66)\x0D\x0A
2020-05-12T06:15:21.428Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.467Z DEBUG modem >> AT+CMEE?\x0D\x0A
2020-05-12T06:15:21.504Z DEBUG modem << +CMEE: 0\x0D\x0A
2020-05-12T06:15:21.505Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.507Z DEBUG modem >> AT+CMEE=1\x0D\x0A
2020-05-12T06:15:21.511Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.557Z DEBUG modem >> AT+CNEC?\x0D\x0A
2020-05-12T06:15:21.601Z DEBUG modem << +CNEC: 0\x0D\x0A
2020-05-12T06:15:21.603Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.606Z DEBUG modem >> AT+CNEC=24\x0D\x0A
2020-05-12T06:15:21.651Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.675Z DEBUG modem >> AT+CGEREP?\x0D\x0A
2020-05-12T06:15:21.698Z DEBUG modem << +CGEREP: 0,0\x0D\x0A
2020-05-12T06:15:21.700Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.702Z DEBUG modem >> AT+CGDCONT?\x0D\x0A
2020-05-12T06:15:21.751Z DEBUG modem << +CGDCONT: 0,"IPV4V6","cmw500.rohde-schwarz.com","192.168.1.30 FC01:ABAB:CDCD:EFE0:0000:0000:0000:0001",0,0\x0D\x0A
2020-05-12T06:15:21.753Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.758Z DEBUG modem >> AT+CGACT?\x0D\x0A
2020-05-12T06:15:21.803Z DEBUG modem << +CGACT: 0,1\x0D\x0A
2020-05-12T06:15:21.804Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.843Z DEBUG modem >> AT+CGEREP=1\x0D\x0A
2020-05-12T06:15:21.874Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:21.900Z DEBUG modem >> AT+CIND=1,1,1\x0D\x0A
2020-05-12T06:15:21.943Z DEBUG modem << OK\x0D
2020-05-12T06:15:21.984Z DEBUG modem >> AT+CEREG=2\x0D\x0A
2020-05-12T06:15:22.029Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.032Z DEBUG modem >> AT+CEREG?\x0D\x0A
2020-05-12T06:15:22.078Z DEBUG modem << +CEREG: 2,1,"0001","00000100",7\x0D\x0A
2020-05-12T06:15:22.079Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.106Z DEBUG modem >> AT+COPS=3,2\x0D\x0A
2020-05-12T06:15:22.128Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.150Z DEBUG modem >> AT+COPS?\x0D\x0A
2020-05-12T06:15:22.191Z DEBUG modem << +COPS: 0,2,"00101",7\x0D\x0A
2020-05-12T06:15:22.193Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.228Z DEBUG modem >> AT%XCBAND\x0D\x0A
2020-05-12T06:15:22.254Z DEBUG modem << %XCBAND: 13\x0D\x0A
2020-05-12T06:15:22.256Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.283Z DEBUG modem >> AT+CGDCONT?\x0D\x0A
2020-05-12T06:15:22.308Z DEBUG modem << +CGDCONT: 0,"IPV4V6","cmw500.rohde-schwarz.com","192.168.1.30 FC01:ABAB:CDCD:EFE0:0000:0000:0000:0001",0,0\x0D\x0A
2020-05-12T06:15:22.311Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.360Z DEBUG modem >> AT+CGACT?\x0D\x0A
2020-05-12T06:15:22.403Z DEBUG modem << +CGACT: 0,1\x0D\x0A
2020-05-12T06:15:22.425Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.455Z DEBUG modem >> AT%CESQ=1\x0D\x0A
2020-05-12T06:15:22.499Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.502Z DEBUG modem >> AT+CESQ\x0D\x0A
2020-05-12T06:15:22.508Z DEBUG modem << +CESQ: 99,99,255,255,28,77\x0D\x0A
2020-05-12T06:15:22.509Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.513Z DEBUG modem >> AT%XSIM=1\x0D\x0A
2020-05-12T06:15:22.538Z DEBUG modem << OK\x0D
2020-05-12T06:15:22.570Z DEBUG modem >> AT%XSIM?\x0D\x0A
2020-05-12T06:15:22.620Z DEBUG modem << %XSIM: 1\x0D\x0A
2020-05-12T06:15:22.622Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.674Z DEBUG modem >> AT+CPIN?\x0D\x0A
2020-05-12T06:15:22.719Z DEBUG modem << +CPIN: READY\x0D\x0A
2020-05-12T06:15:22.720Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.758Z DEBUG modem >> AT+CPINR="SIM PIN"\x0D\x0A
2020-05-12T06:15:22.797Z DEBUG modem << +CPINR: "SIM PIN",3\x0D\x0A
2020-05-12T06:15:22.799Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.827Z DEBUG modem >> AT+CIMI\x0D\x0A
2020-05-12T06:15:22.851Z DEBUG modem << 001010123456063\x0D\x0A
2020-05-12T06:15:22.853Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:15:22.855Z INFO IMSIdentity: 001010123456063
2020-05-12T06:15:59.130Z DEBUG modem >> AT+CGATT=0\x0D\x0A
2020-05-12T06:16:00.130Z ERROR Error: 'AT+CGATT=0
' timed out
2020-05-12T06:16:03.661Z DEBUG modem >> AT\x0D\x0A
2020-05-12T06:16:04.661Z ERROR Error: 'AT
' timed out
2020-05-12T06:16:04.662Z DEBUG modem >> AT\x0D\x0A
2020-05-12T06:16:05.663Z ERROR Error: 'AT
' timed out
2020-05-12T06:16:08.315Z DEBUG modem >> AT+CFUN?\x0D\x0A
2020-05-12T06:16:09.316Z ERROR Error: 'AT+CFUN?
' timed out

Fullscreen issue2.txt Download

2020-05-12T06:19:02.034Z DEBUG modem >> AT+CFUN?\x0D\x0A
2020-05-12T06:19:02.039Z DEBUG modem << +CFUN: 1\x0D
2020-05-12T06:19:02.045Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.046Z DEBUG modem >> AT+CGSN=1\x0D\x0A
2020-05-12T06:19:02.051Z DEBUG modem << +CGSN: "352656100378499"\x0D
2020-05-12T06:19:02.052Z DEBUG modem << \x0A
2020-05-12T06:19:02.053Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.082Z DEBUG modem >> AT+CGMI\x0D\x0A
2020-05-12T06:19:02.088Z DEBUG modem << Nordic Semiconductor ASA\x0D\x0A
2020-05-12T06:19:02.091Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.095Z DEBUG modem >> AT+CGMM\x0D\x0A
2020-05-12T06:19:02.144Z DEBUG modem << nRF9160-SICA\x0D\x0A
2020-05-12T06:19:02.145Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.149Z DEBUG modem >> AT+CGMR\x0D\x0A
2020-05-12T06:19:02.178Z DEBUG modem << mfw_nrf9160_1.1.1\x0D\x0A
2020-05-12T06:19:02.182Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.185Z INFO Nordic Semiconductor ASA nRF9160-SICA [mfw_nrf9160_1.1.1] SerNr: 352656100378499
2020-05-12T06:19:02.186Z DEBUG modem >> AT+CEMODE?\x0D\x0A
2020-05-12T06:19:02.191Z DEBUG modem << +CEMODE: 2\x0D\x0A
2020-05-12T06:19:02.192Z DEBUG modem << OK\x0D
2020-05-12T06:19:02.227Z DEBUG modem >> AT%XCBAND=?\x0D\x0A
2020-05-12T06:19:02.237Z DEBUG modem << %XCBAND: (1,2,3,4,5,8,12,13,14,17,18,19,20,25,26,28,66)\x0D\x0A
2020-05-12T06:19:02.240Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.280Z DEBUG modem >> AT+CMEE?\x0D\x0A
2020-05-12T06:19:02.284Z DEBUG modem << +CMEE: 0\x0D
2020-05-12T06:19:02.326Z DEBUG modem << \x0A
2020-05-12T06:19:02.327Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.330Z DEBUG modem >> AT+CMEE=1\x0D\x0A
2020-05-12T06:19:02.367Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.371Z DEBUG modem >> AT+CNEC?\x0D\x0A
2020-05-12T06:19:02.375Z DEBUG modem << +CNEC: 0\x0D\x0A
2020-05-12T06:19:02.378Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.381Z DEBUG modem >> AT+CNEC=24\x0D\x0A
2020-05-12T06:19:02.446Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.450Z DEBUG modem >> AT+CGEREP?\x0D\x0A
2020-05-12T06:19:02.457Z DEBUG modem << +CGEREP: 0,0\x0D\x0A
2020-05-12T06:19:02.459Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.532Z DEBUG modem >> AT+CGDCONT?\x0D\x0A
2020-05-12T06:19:02.584Z DEBUG modem << +CGDCONT: 0,"IPV4V6","cmw500.rohde-schwarz.com","192.168.1.30 FC01:ABAB:CDCD:EFE0:0000:0000:0000:0001",0,0\x0D\x0A
2020-05-12T06:19:02.585Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.590Z DEBUG modem >> AT+CGACT?\x0D\x0A
2020-05-12T06:19:02.638Z DEBUG modem << +CGACT: 0,1\x0D\x0A
2020-05-12T06:19:02.640Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.670Z DEBUG modem >> AT+CGEREP=1\x0D\x0A
2020-05-12T06:19:02.720Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.756Z DEBUG modem >> AT+CIND=1,1,1\x0D\x0A
2020-05-12T06:19:02.790Z DEBUG modem << OK\x0D
2020-05-12T06:19:02.823Z DEBUG modem >> AT+CEREG=2\x0D\x0A
2020-05-12T06:19:02.854Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.881Z DEBUG modem >> AT+CEREG?\x0D\x0A
2020-05-12T06:19:02.929Z DEBUG modem << +CEREG: 2,1,"0001","00000100",7\x0D\x0A
2020-05-12T06:19:02.931Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:02.961Z DEBUG modem >> AT+COPS=3,2\x0D\x0A
2020-05-12T06:19:02.993Z DEBUG modem << OK\x0D
2020-05-12T06:19:03.021Z DEBUG modem >> AT+COPS?\x0D\x0A
2020-05-12T06:19:03.051Z DEBUG modem << +COPS: 0,2,"00101",7\x0D\x0A
2020-05-12T06:19:03.054Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.117Z DEBUG modem >> AT%XCBAND\x0D\x0A
2020-05-12T06:19:03.153Z DEBUG modem << %XCBAND: 13\x0D\x0A
2020-05-12T06:19:03.154Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.200Z DEBUG modem >> AT+CGDCONT?\x0D\x0A
2020-05-12T06:19:03.249Z DEBUG modem << +CGDCONT: 0,"IPV4V6","cmw500.rohde-schwarz.com","192.168.1.30 FC01:ABAB:CDCD:EFE0:0000:0000:0000:0001",0,0\x0D\x0A
2020-05-12T06:19:03.251Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.254Z DEBUG modem >> AT+CGACT?\x0D\x0A
2020-05-12T06:19:03.259Z DEBUG modem << +CGACT: 0,1\x0D\x0A
2020-05-12T06:19:03.260Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.292Z DEBUG modem >> AT%CESQ=1\x0D\x0A
2020-05-12T06:19:03.343Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.393Z DEBUG modem >> AT+CESQ\x0D\x0A
2020-05-12T06:19:03.424Z DEBUG modem << +CESQ: 99,99,255,255,28,77\x0D\x0A
2020-05-12T06:19:03.427Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.475Z DEBUG modem >> AT%XSIM=1\x0D\x0A
2020-05-12T06:19:03.506Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.539Z DEBUG modem >> AT%XSIM?\x0D\x0A
2020-05-12T06:19:03.567Z DEBUG modem << %XSIM: 1\x0D
2020-05-12T06:19:03.595Z DEBUG modem << \x0A
2020-05-12T06:19:03.597Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.666Z DEBUG modem >> AT+CPIN?\x0D\x0A
2020-05-12T06:19:03.696Z DEBUG modem << +CPIN: READY\x0D\x0A
2020-05-12T06:19:03.698Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.746Z DEBUG modem >> AT+CPINR="SIM PIN"\x0D\x0A
2020-05-12T06:19:03.794Z DEBUG modem << +CPINR: "SIM PIN",3\x0D\x0A
2020-05-12T06:19:03.797Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.843Z DEBUG modem >> AT+CIMI\x0D\x0A
2020-05-12T06:19:03.872Z DEBUG modem << 001010123456063\x0D\x0A
2020-05-12T06:19:03.874Z DEBUG modem << OK\x0D\x0A\x00
2020-05-12T06:19:03.876Z INFO IMSIdentity: 001010123456063
2020-05-12T06:19:23.015Z DEBUG modem >> AT+CFUN=0\x0D\x0A
2020-05-12T06:19:24.015Z ERROR Error: 'AT+CFUN=0
' timed out

[Martin Lesund]

Hi Praveen,
I have build the Serial LTE Modem sample with the included fix that Håkon mentioned.
serial_lte_modem_15_05.hex

Please try this version and you should not get this modem "forever" hand.

BR,
Martin l.

[d4L]

Hello. I have tested that firmware. Now modem does not stuck after few AT commands, now it just ignores them, it handles AT commands too slow. Without 100ms delays it just ignores, at least doesn't brick as it was before. This firmware fixed bricking, but not speed of AT cmd handling which is way too slow.

[Martin Lesund]

Hi d4L,
Which serial terminal do you use on the computer side?

[d4L]

Hi there. The one(UART) which is used to send special BSD lib TCP commands and regular AT commands.
Anyway I have fixed that issue. Just moded serial lte modem source, so now this example is much more responsive and does not have constant 100ms delay.
Seems there are no side effects. So it is ok for me.

[Martin Lesund]

Hi d4L,
Would you like to share what you have changed in the code so we could take a look, and if it's actually benefiting the sample we could add it & merge it with the existing sample.