Transmit GPS data to website

[tracking]

Hello 

I would like to transmit gps data to my website in addition to nrf cloud, there is a example or documentation about this that I can take of reference? I am working with nRF 9160 DK 

thanks in advance.

Kind Regards

Julio

[Håkon Alseth]

Hi,

 

The asset_tracker shows how to connect to a cloud based system, and send certain sensors + gps data to the cloud.

If you want a simpler solution, like a tcp/udp connection directly to your own server, I would recommend that you look at the "gps" sample, and add your own implementation around this.

 

Note that there's a restriction towards getting GPS and LTE concurrent, which is that you have to be in eDRX or PSM mode in order to use the GPS. A recommended use-case is to use the AT CSCON event to signal when you can or cannot use the GPS.

 

Kind regards,

Håkon

[paul_tanner]

Thx Håkon,

I tried setting CSCON=0 when initialising the GPS.

(After looking at the code in asset_tracker I also saw it use lte_lc_psm_req(true))

If I then try to initialise a UDP connection lte_lc_init_and_connect_async(lte_handler) fails.

(Initialisation code from the UDP example)

I'm not clear on the sequence I need to initialise both GPS and UDP.

further...

I wanted to see why lte_lc_init_and_connect_async is failing but this seems to be part of the distribution that is shipped in binary.

Specifically, the error is:

modem_configure()
I: Using legacy LTE PCO mode...
I: PDP Context: AT+CGDCONT=0,"IP","lpwa.vodafone.iot"
E: Could not send AT command, error: -8

Which is odd because when initialising the GPS we already sent 4 AT commands without error.

This part of UDP initialisation works fine if I comment out the GPS initialisation 

Thx.

[Håkon Alseth]

Hi Paul,

 

My strongest apologies! This comment from me is written a bit too fast (ie: its wrong..)

Håkon Alseth said:

Please check that "modem_configure()" isn't called

You should check that modem_configure hasn't been called yet, before setting system permissions, like XSYSTEMMODE.

So, issue your AT-commands, then call modem_configure() to connect to the LTE network.

 

Kind regards,

Håkon 

[paul_tanner]

Thx Håkon 

I tried that.  It gets to modem_configure() - same code as in UDP sample - and we then fail with:

```

Could not send AT command error -8

```

This is happening inside lte_lc_init_and_connect_async() for which AFAIK we do not have the source.

Regards. 

[Håkon Alseth]

Hi,

 

paul_tanner said:

This is happening inside lte_lc_init_and_connect_async() for which AFAIK we do not have the source.

That function is inside lte_lc.c: https://github.com/nrfconnect/sdk-nrf/blob/master/lib/lte_link_control/lte_lc.c#L744

Do you know which AT command is failing? Does any of them work?

 

Kind regards,

Håkon

[paul_tanner]

Thx Håkon 

OK. modem_configure() is trying to set the AT%XSYSTEMMODE - which is *already* correctly set.

(I have CONFIG_LTE_NETWORK_MODE_NBIOT_GPS=y in prj.conf)

BTW. To find this out I had to edit lte_lc.c whereas I would have preferred to turn on debugging.  I tried adding:

  #define NRF_AT_CMD_LOG_LEVEL NRF_LOG_LEVEL_DEBUG

in main.c but that had no effect.

What next?

Regards.

[paul_tanner]

So I made that error in modem_configure() non-fatal (a hack in ltc_lc.c) and it now does GPS and transmits the result via UDP.  This is almost a solution apart from the fact that I hacked ltc_lc.c.  I'd like a way to do this without that hack if possible to make it more upgrade-proof.

Also, if I want to restrict the log a bit i'd like to find out where CONFIG_LTE_LINK_CONTROL_LOG_LEVEL is defined.

Thx for any suggestions.

Regards

[Håkon Alseth]

Hi,

 

Don't change the source files, you should set the log level on a project level:

https://docs.zephyrproject.org/latest/reference/kconfig/CONFIG_LOG_DEFAULT_LEVEL.html

You can access this by entering "menuconfig", either via SeggerEmbeddedStudio (nordic edition) or via command line (cd my-project/build-folder && ninja menuconfig)

Then you should also choose "LTE_LINK_CONTROL_LOG_LEVEL_DBG".

 

Kind regards,

Håkon