Can not run GPS example code available in nRF Connect SDKv1.0.0 on nRF9160 DK.

[Jagir008]

Hello,

I am working on nRF9160 DK development platform.

For that i Compile & run GPS example, But while debuging that example i find that mcu stucks in CPU Idle function for infinite period of time.

And this is happening while creating a socket.

I Assume that sample example code should not have any issue it should run flawlessly, i think i am missing soemthing while creating an environment / installing SDK & toolchain.

Please let know the solution of this issue.

[Håkon Alseth]

Hi,

 

Is this the example you're running?

https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/v1.0.0/samples/nrf9160/gps/src/main.c

Does the UART print anything? Could you share the logs?

 

Kind regards,

Håkon

[Jagir008]

yes, i am running that example

By debugging i found that mcu goes into cpu_idle state(Infinite loop) while creating socket for enabling GPS.

Debug logs are:

***** Booting Zephyr OS v1.14.99-ncs2 *****
Staring GPS application
Failed to enable GPS

After GPS enable fail printed cpu goes into infinite idle state.

Also i checked to LTE Monitor link to get AT command response But in that also i am not getting any response form device.

 

[Jagir008]

Thanks Hakon,

After updating firmware now i can communicate to Modem in LTE Monitor App & Also GPS Sample Application is working, 

But it is not giving me any of GPS Co-ordinate Data.

NMEA data string is 0,0,0.. for all NMEA formats(GSA,GSV,GGA etc)

From LTE monitor APP i am not able to turn off modem once it is turned ON, Using AT command "AT+CFUN=4".

Where can i get pre-build .hex file for sample applications ?

[Håkon Alseth]

In order to get valid GPS data, you need to be outdoors. You are very unlikely to get a GPS fix inside.

 

Jagir008 said:

Where can i get pre-build .hex file for sample applications ?

 Unfortunately, we do not provide precompiled hex files, but once built; it should be present as a "merged.hex" in your ../my-application/build-folder/zephyr folder. If you haven't setup the toolchain, please see this tutorial on how to get started with NCS:

https://devzone.nordicsemi.com/nordic/cellular-iot-guides/b/getting-started-cellular/posts/nrf-connect-sdk-tutorial

Kind regards,

Håkon

[Jagir008]

Okay Thanks Hakon,

Can we have a document about required functions/parameters for GPS ?

Because i go through sample application i found few of the params like GPS_START/STOP flag & intervals that i did not get exactly.

Why are we using socket for GPS/LTE modem communication ?

[Jagir008]

I was looking into HTTP sample example in your Git repo.

If we want to Use LTE via HTTP & GPS in same application,

We need to keep changing AT_XSYSTEMMODE & AT_MAGPIO values, right ?

What should be param values for "AT_MAGPIO"  if i want to use LTE ?

Before using GPS/LTE Do we need to set AT_XSYSTEMMODE & AT_MAGPIO by Power Off modem (AT+CFUN=4) & Again Power On, Is this required to done every time ? 

[Håkon Alseth]

Jagir008 said:

We need to keep changing AT_XSYSTEMMODE & AT_MAGPIO values, right ?

 XSYSTEMMODE states what your system should enable.

For instance; NB1 + GPS, or M1 + GPS, or only GPS/M1/NB1.

 

Note that in order to use the GPS in combination with either NB1 or M1, you need to be in power saving mode (PSM) on the network you're attached to.

MAGPIO is more about your specific design, for instance if you need to switch in certain antenna tuners for the specific bands (incl. the GPS band).

 

You can read more about each of these in the AT command specification:

https://infocenter.nordicsemi.com/topic/ref_at_commands/REF/at_commands/mob_termination_ctrl_status/xsystemmode_set.html?cp=2_1_3_29_0

https://infocenter.nordicsemi.com/topic/ref_at_commands/REF/at_commands/sip_pin_configuration/xmagpio_set.html?cp=2_1_4_1_0

Jagir008 said:

What should be param values for "AT_MAGPIO"  if i want to use LTE ?

If you're using the nRF91-DK, you do need to touch this, as it's already setup for you.

Jagir008 said:

Before using GPS/LTE Do we need to set AT_XSYSTEMMODE & AT_MAGPIO by Power Off modem (AT+CFUN=4) & Again Power On, Is this required to done every time ? 

With modem v1.0.0 and newer, it is now possible to use the GPS while in PSM mode, ie: without powering the modem off/applying new settings/on again.

Here's an simplified example for running LTE M1 + GPS.  

https://github.com/Rallare/fw-nrfconnect-nrf/blob/nrf9160_samples/samples/nrf9160/udp_gps/src/main.c

 

Kind regards,

Håkon

[Jagir008]

For HTTP Sample Application,

If i right click on "getaddrinfo" function to see it's function definition,

I see definition of  "net_getaddrinfo_addr_str" function.

Is both the function are same ?

Where to find any #ifdef for this function conversion ?

I observed same thing in many of functions in Nordic SDK proects.

[Håkon Alseth]

Hi,

 

Jagir008 said:

If i right click on "getaddrinfo" function to see it's function definition,

I see definition of  "net_getaddrinfo_addr_str" function.

Is both the function are same ?

Where to find any #ifdef for this function conversion ?

 

Please see nrf91_sockets.c for the socket offloading translation for the nRF9160. The reason why its like this is because its a syscall API that is wrapped around, as there's several other implementations for sockets in zephyr itself. If you have trouble finding the implementations, I'd recommend to enter debug mode and single-step through the functions that you're interested in.

 

Kind regards,

Håkon