GPS and LTE issue

[Laurin Rossmeier]

Hello,

Ive been trying to get simultaneous GPS reception and LTE connectivity for a while now. I've read that this wasn't possibe in the past but it looks like it should be possible now.

Im using the latest Asset Tracker and modem FW v1.0.1 on a nrf9160DK ver 0.8.5 . I configured the asset tracker to use NB-IOT + GPS. 

When i long press the button it enables PSM and GPS and tries to find a Fix for ~6 minutes until it restarts the gps again and again....

Using the gps example programm i get a fix in ~2 minutes.

Is it supposed to work like this or is this  still in development? 

Is there a way to get debug nmea output in the console?

Console output:

2019-09-10T06:47:08.304Z DEBUG modem << [00:01:01.312,591] \x1B[0m<dbg> nrf_cloud_transport.nct_mqtt_evt_handler: MQTT_EVT_PUBACK: id=7890 result=0\x1B[0m\x0D\x0A
2019-09-10T06:47:08.847Z DEBUG modem << [00:01:01.322,387] \x1B[0m<dbg> nrf_cloud_transport.nct_dc_connect: nct_dc_connect\x1B[0m\x0D\x0A
2019-09-10T06:47:08.852Z DEBUG modem << [00:01:01.330,902] \x1B[0m<dbg> nrf_cloud.nfsm_set_current_state_and_notify: state: 13\x1B[0m\x0D\x0A
2019-09-10T06:47:09.371Z DEBUG modem << [00:01:02.272,674] \x1B[0m<dbg> nrf_cloud_transport.nct_mqtt_evt_handler: MQTT_EVT_SUBACK: id=8765 result=0\x1B[0m\x0D\x0A
2019-09-10T06:47:09.378Z DEBUG modem << [00:01:02.282,470] \x1B[0m<dbg> nrf_cloud.nfsm_set_current_state_and_notify: state: 14\x1B[0m\x0D\x0A
2019-09-10T06:47:09.384Z DEBUG modem << [00:01:02.290,374] \x1B[0m<dbg> nrf_cloud.event_handler: NRF_CLOUD_EVT_READY\x1B[0m\x0D\x0A
2019-09-10T06:47:09.388Z DEBUG modem << CLOUD_EVT_READY\x0D\x0A
2019-09-10T06:47:09.392Z DEBUG modem << GPS initialized\x0D\x0A
2019-09-10T06:48:12.250Z DEBUG modem << Starting GPS\x0D\x0A
2019-09-10T06:48:13.252Z DEBUG modem << Enabling PSM\x0D\x0A
2019-09-10T06:48:13.770Z DEBUG modem << PSM enabled\x0D\x0A
2019-09-10T06:48:14.303Z DEBUG modem << [00:02:07.282,379] \x1B[0m<dbg> nrf9160_gps.enable_gps: GPS mode is enabled\x1B[0m\x0D\x0A
2019-09-10T06:48:14.309Z DEBUG modem << [00:02:07.289,733] \x1B[0m<dbg> nrf9160_gps.enable_gps: Functional mode: 1\x1B[0m\x0D\x0A
2019-09-10T06:48:14.314Z DEBUG modem << [00:02:07.296,875] \x1B[0m<dbg> nrf9160_gps.start: GPS socket created\x1B[0m\x0D\x0A
2019-09-10T06:48:14.320Z DEBUG modem << [00:02:07.306,976] \x1B[0m<dbg> nrf9160_gps.start: GPS operational\x1B[0m\x0D\x0A
2019-09-10T06:48:14.324Z DEBUG modem << GPS started successfully.\x0D\x0A
2019-09-10T06:48:14.328Z DEBUG modem << Searching for satellites to get position fix. This may take several minutes.\x0D\x0A
2019-09-10T06:48:14.827Z DEBUG modem << The device will attempt to get a fix for 360 seconds, before the GPS is stopped.\x0D\x0A
2019-09-10T06:48:14.832Z DEBUG modem << GPS operation started\x0D\x0A
2019-09-10T06:54:14.307Z DEBUG modem << [00:08:07.331,787] \x1B[0m<dbg> nrf9160_gps.stop: Stopping GPS\x1B[0m\x0D\x0A
2019-09-10T06:54:14.921Z DEBUG modem << GPS operation was stopped\x0D\x0A
2019-09-10T06:54:14.928Z DEBUG modem << The device will try to get fix again in 30 seconds\x0D\x0A
2019-09-10T06:54:44.315Z DEBUG modem << Enabling PSM\x0D\x0A
2019-09-10T06:54:44.883Z DEBUG modem << PSM enabled\x0D\x0A
2019-09-10T06:54:45.496Z DEBUG modem << [00:08:38.357,604] \x1B[0m<dbg> nrf9160_gps.enable_gps: GPS mode is enabled\x1B[0m\x0D\x0A
2019-09-10T06:54:45.502Z DEBUG modem << [00:08:38.365,020] \x1B[0m<dbg> nrf9160_gps.enable_gps: Functional mode: 1\x1B[0m\x0D\x0A
2019-09-10T06:54:45.510Z DEBUG modem << [00:08:38.375,427] \x1B[0m<dbg> nrf9160_gps.start: GPS operational\x1B[0m\x0D\x0A
2019-09-10T06:54:45.515Z DEBUG modem << GPS started successfully.\x0D\x0A
2019-09-10T06:54:45.519Z DEBUG modem << Searching for satellites to get position fix. This may take several minutes.\x0D\x0A
2019-09-10T06:54:45.523Z DEBUG modem << The device will attempt to get a fix for 360 seconds, before the GPS is stopped.\x0D\x0A
2019-09-10T06:54:45.528Z DEBUG modem << GPS operation started\x0D\x0A
2019-09-10T07:00:45.364Z DEBUG modem << [00:14:38.400,238] \x1B[0m<dbg> nrf9160_gps.stop: Stopping GPS\x1B[0m\x0D\x0A
2019-09-10T07:00:45.873Z DEBUG modem << GPS operation was stopped\x0D\x0A
2019-09-10T07:00:46.448Z DEBUG modem << The device will try to get fix again in 30 seconds\x0D\x0A
2019-09-10T07:01:15.371Z DEBUG modem << Enabling PSM\x0D\x0A
2019-09-10T07:01:15.986Z DEBUG modem << PSM enabled\x0D\x0A
2019-09-10T07:01:16.554Z DEBUG modem << [00:15:09.425,292] \x1B[0m<dbg> nrf9160_gps.enable_gps: GPS mode is enabled\x1B[0m\x0D\x0A
2019-09-10T07:01:16.561Z DEBUG modem << [00:15:09.438,842] \x1B[0m<dbg> nrf9160_gps.enable_gps: Functional mode: 1\x1B[0m\x0D\x0A
2019-09-10T07:01:16.565Z DEBUG modem << [00:15:09.455,627] \x1B[0m<dbg> nrf9160_gps.start: GPS operational\x1B[0m\x0D\x0A
2019-09-10T07:01:16.569Z DEBUG modem << GPS started successfully.\x0D\x0A
2019-09-10T07:01:16.574Z DEBUG modem << Searching for satellites to get position fix. This may take several minutes.\x0D\x0A
2019-09-10T07:01:16.581Z DEBUG modem << The device will attempt to get a fix for 360 seconds, before the GPS is stopped.\x0D\x0A
2019-09-10T07:01:16.585Z DEBUG modem << GPS operation started\x0D\x0A
2019-09-10T07:07:16.432Z DEBUG modem << [00:21:09.480,438] \x1B[0m<dbg> nrf9160_gps.stop: Stopping GPS\x1B[0m\x0D\x0A
2019-09-10T07:07:16.969Z DEBUG modem << GPS operation was stopped\x0D\x0A
2019-09-10T07:07:17.507Z DEBUG modem << The device will try to get fix again in 30 seconds\x0D\x0A
2019-09-10T07:07:46.440Z DEBUG modem << Enabling PSM\x0D\x0A
2019-09-10T07:07:46.951Z DEBUG modem << PSM enabled\x0D\x0A
2019-09-10T07:07:47.531Z DEBUG modem << [00:21:40.506,286] \x1B[0m<dbg> nrf9160_gps.enable_gps: GPS mode is enabled\x1B[0m\x0D\x0A
2019-09-10T07:07:47.537Z DEBUG modem << [00:21:40.513,702] \x1B[0m<dbg> nrf9160_gps.enable_gps: Functional mode: 1\x1B[0m\x0D\x0A
2019-09-10T07:07:47.543Z DEBUG modem << [00:21:40.524,169] \x1B[0m<dbg> nrf9160_gps.start: GPS operational\x1B[0m\x0D\x0A
2019-09-10T07:07:47.547Z DEBUG modem << GPS started successfully.\x0D\x0A
2019-09-10T07:07:47.552Z DEBUG modem << Searching for satellites to get position fix. This may take several minutes.\x0D\x0A
2019-09-10T07:07:47.556Z DEBUG modem << The device will attempt to get a fix for 360 seconds, before the GPS is stopped.\x0D\x0A
2019-09-10T07:07:47.560Z DEBUG modem << GPS operation started\x0D\x0A

Thanks in advance!

[Håkon Alseth]

Hi,

 

What SIM card are you using? Our experience shows that some vendors do not allow PSM on roaming SIM cards. Could you check with AT client to verify if you enter PSM mode?

There's a "how to" on reading out PSM values here: https://devzone.nordicsemi.com/f/nordic-q-a/48200/correct-to-shutdown-modem-and-reconnect

 

Kind regards,

Håkon

[Laurin Rossmeier]

I'm using a Telekom Austria nb iot Sim which works just fine in PSM, I just don't get any gps Data.

[Håkon Alseth]

What does CEREG give back?

AT+CEREG=5
AT+CEREG?

[Laurin Rossmeier]

The Response is: 

AT+CEREG?
+CEREG: 5,1,"C35F","0011E8CE",9,,,"11100000","11100000"

[Håkon Alseth]

Hi,

 

Unfortunately, 111 in the MSBits indicates that you are not going into PSM mode (111 = PSM disabled).

 

Kind regards,

Håkon

[Laurin Rossmeier]

Well, my bad, the prevoius test wasnt in PSM

Now I tried it after i long pressed the button and after it said PSM enabled

Now the result is : +CEREG: 5,1,"C35F","0011E8CE",9,,,"11100000","00011111"

Thank you,

Laurin

[Håkon Alseth]

That is good! Did the GPS start tracking as well?

 

Kind regards,

Håkon

[Laurin Rossmeier]

It says that the device will attempt to get a fix for 360 seconds and after that time it stops.

I,ve tried the gps example in the exact same location and it got a fix in under 2 minutes. I even used the Thingy91 in an open area outside with no luck.

[Håkon Alseth]

Hi,

 

If it has entered PSM mode successfully, and you do not have any on-going IP traffic, it should start printing info, like this:

+CEREG: 5,1,"76C1","0102DA04",7,,,"11100000","00001111"
OK
Starting GPS
Enabling PSM
PSM enabled
[00:02:05.143,432] <dbg> nrf9160_gps.enable_gps: GPS mode is enabled
[00:02:05.150,726] <dbg> nrf9160_gps.enable_gps: Functional mode: 1
[00:02:05.157,562] <dbg> nrf9160_gps.start: GPS socket created
[00:02:05.167,999] <dbg> nrf9160_gps.start: GPS operational
GPS started successfully.
Searching for satellites to get position fix. This may take several minutes.
The device will attempt to get a fix for 360 seconds, before the GPS is stopped.
GPS operation started
[00:02:30.932,312] <dbg> nrf9160_gps.print_satellite_stats: Tracking: 0 Using: 0 Unhealthy: 0
[00:02:30.941,528] <dbg> nrf9160_gps.print_satellite_stats: Seconds since last fix 150
.....

 

If you are not able to enter PSM, like if the mqtt thread is still sending/receiving data, it still stop like in your print outs.

Could you try waiting a minute or so before turning on the GPS?

 

Kind regards,

Håkon