Latitude always returns as "0"? - ArduinoIDE version with Chirpstack decoder

[dvisser]

I have deployed this solution using the ArduinoIDE version and used the chirpstack decoder, however the returned gps latitude is always "0" whilst longitude appears correct.
Please can this issue be addresses?
All other functionality appears to be working correctly.

[dvisser]

I skimmed the code and it doesnt appear obvious at first glance. I am using Wisblock 2 kit also (RAK1900 GPS module, so it uses the TinyGPSPlus library).

@beegee-tokyo what do you think?

[beegee-tokyo]

I guess you are using the latest code from this repo. What payload decoder are you using in Chirpstack?
I was testing with our RAKwireless_Standardized_Payload.

Just run a test and it works as expected.

BLE Log:

10:44:48->GNSS Task wake up
10:44:48->
10:44:48->+EVT:START_LOCATION
10:44:48->poll_gnss
10:44:48->
10:44:48->GNSS timeout 90000
10:44:48->
10:44:48->Using RAK1910
10:44:48->
10:45:23->Location valid
10:45:23->
10:45:23->Location valid
10:45:23->
10:45:23->Altitude valid
10:45:23->
10:45:23->Lat: 14.4214 Lon: 121.0069
10:45:23->
10:45:23->Alt: 55.30
10:45:23->
10:45:23->Acy: 99.99
10:45:23->
10:45:23->+EVT:LOCATION FIX
10:45:23->GNSS Task finished
10:45:23->
10:45:28->Packet enqueued
10:45:28->
10:45:31->LPWAN TX cycle finished ACK
10:45:31->
10:45:31->+EVT:SEND OK

Output in Chirpstack:

[dvisser]

Yes I am using the latest code. However, I used the chirpstack decoder from the decoder folder and not the one you mentioned.

I will try the decoder you suggest on Monday and advise.

Thankyou for the prompt response.

[dvisser]

Hi @beegee-tokyo I had to modify the decoder you mention slightly such that it would work with latest chirpstack version (decodeUplink method with input and requirement to return 'data').

See below output, as latitude is still reading 0.

function decodeUplink(input) {

	bytes = input.bytes;
	fPort = input.fPort;

	// flat output (like original decoder):
	var response = {};
	lppDecode(bytes, 1).forEach(function (field) {
		response[field['name'] + '_' + field['channel']] = field['value'];
	});
  
	return {
       data: {
           response
         }
   	 }; 
}

[dvisser]

I have also set "AT+GNSS=1" as well if that helps?

[beegee-tokyo]

What do you get in the direct log output of the device?
Like what I showed in my test:

10:44:48->Using RAK1910
10:44:48->
10:45:23->Location valid
10:45:23->
10:45:23->Location valid
10:45:23->
10:45:23->Altitude valid
10:45:23->
10:45:23->Lat: 14.4214 Lon: 121.0069
10:45:23->
10:45:23->Alt: 55.30
10:45:23->
10:45:23->Acy: 99.99
10:45:23->

You can get this through USB and it should be as well available on BLE UART connection.

[dvisser]

OK so firmware confirmed to be 1.1.2 Jan 17 2023 13:24:19

I also tried your RAKwireless_Standardized_Payload decoder.

I am still getting latitude of 0, as well as on the local log output of the device via USB, I will screenshot a copy of the output for you.

[dvisser]

[beegee-tokyo]

That is strange, I know there was a problem with negative lat/long values before, but that was solved.

What is the latitude that you would expect to get?
Do you have by any chance another RAK1910 module that you could try to use?

[dvisser]

I have six wisblock kits here all doing the same thing.

[beegee-tokyo]

So what is the expected latitude?

Testing here with the latest firmware version works fine.

[dvisser]

approx -24.4428XX

[beegee-tokyo]

You are testing outside of a building or inside?
I cannot find any problem and the negative latitude should be no problem. RAK members in South America tested it and they are on negative lat and negative long.

[dvisser]

I am outside

[beegee-tokyo]

I have honestly no idea what happens.
I cannot see any problem when testing here.
Can you try our very simple RAK1910 example code? But it requires a laptop connected to see the output.
RAK1910_GPS_UBLOX7