How can I evaluate that AGPS data downloaded and been processed?

[Roman Veselskyi]

Hello,

I’m trying to understand exactly how the location module works in the Assert Tracker V2 application. I want to see the NMEA data in the logs, but I’m not sure how to enable it or if that’s even possible. My main goal is to confirm that the AGPS data downloaded by the library has been processed. It’s easy to see this in the GNSS sample, but you don’t see the same information in the Assert Tracker’s PVT data.

[Simonr]

Hi

I think it should be sufficient to enable logging for the location library and debug logging in the application. That can be done with referring to the overlay-debug.conf, and building with the following command: thingy91_nrf9160_ns -T applications.asset_tracker_v2.debug .

Also, if you're not aware of it, please check out the Asset Tracker Template that implements a modular application framework for nRF91-based IoT devices.

Best regards,

Simon

[Roman Veselskyi]

Thanks, but logging doesn't provide the NMEA this one I already checked. 

[Simonr]

Hi

The Asset tracker v2 supports location via the location library which only implements handling of PVT frames, so some additions will be needed to also get NMEA logging.

1. Add NMEA handling in the method_gnss_event_handler(): https://github.com/nrfconnect/sdk-nrf/blob/ddc4bdb3db16a2f62d7762e807b1742ab74bdc24/lib/location/method_gnss.c#L376 

2. Add a print function. Something like this for example:

static void print_nmea(struct nrf_modem_gnss_nmea_data_frame *nmea)

{

       if (nmea_output_level == 0) {

               return;

       }



       for (int i = 0; i < NRF_MODEM_GNSS_NMEA_MAX_LEN; i++) {

               if (nmea->nmea_str[i] == '\r' || nmea->nmea_str[i] == '\n') {

                       nmea->nmea_str[i] = '\0';

                       break;

               }

       }



       LOG_WRN("GNSS: NMEA: %s", nmea->nmea_str);

}

Best regards,

Simon

[Roman Veselskyi]

So, I need to update the library code not sure this is a good idea. But even if yes where I will take the data struct nrf_modem_gnss_nmea_data_frame *nmea ? 

[Simonr]

Hi

This was what one of our devs suggested, and these additions are necessary to get NMEA logging up and running I'm afraid. The printing would be handled the same way you would handle or print the PVT frames, so I think you can look at that implementation for reference.

Best regards,

Simon