[Sindre Kopland-Hansen]

Hi again,

I found some useful code here:

https://www.thethingsnetwork.org/forum/t/parsing-semtech-loramote-data/938

and fixed it for the mbox-dot survey GPS:

var decoded_data = new Buffer(msg.payload.payload,’base64′);

var lat_val = decoded_data[3] << 16 | decoded_data[4] << 8 | decoded_data[5];
var lat = !(lat_val&0x800000) ? lat_val : ((0xffffff-lat_val+1)*-1)
var latitude = lat/Math.pow(2,23)*90;

var lon_val = decoded_data[7] << 16 | decoded_data[8] << 8 | decoded_data[9];
var lon = !(lon_val&0x800000) ? lon_val : ((0xffffff-lon_val+1)*-1);
var longitude = lon/Math.pow(2,23)*180;

var temperature = decoded_data[1];

return “lat: ” + latitude + ” lon: ” + longitude + ” temp: ” + temperature;

Just connect to the proper topic, filter json and decode.

(In case someone else should need it)

/BR
Sindre

[Sindre Kopland-Hansen]

Hi Leon,

Connected the topic to node-red in the conduit now and can see the binary packages coming in. Is there any pre-made node in node-red that can decode it? Can’t find any so far ..

/BR
Sindre

[Sindre Kopland-Hansen]

Hi Leon,

Thanks a lot for the answer. This explain my mystery!

So I can connect the node red in the conduit to the ttn mqqt topic and decode it that way?

/BR
Sindre

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