Encoder problem with Javascript

Application Development
1

I am working on an encoder for LoRaWAN with JavaScript. I receive this field of data:

{“header”: 6,“sunrise”: -30,“sunset”: 30,“lat”: 65.500226,“long”: 24.833547}

And I need to encode in an hex message, my code is:

var header = byteToHex(object.header);
var sunrise =byteToHex(object.sunrise);
var sunset = byteToHex(object.sunset);
var la = parseInt(object.lat100,10);
var lat = swap16(la);
var lo = parseInt(object.long100,10);
var lon = swap16(lo);
var message={};
if (object.header === 6){
    message = (lon)|(lat<<8);
    bytes = message;
}
return hexToBytes(bytes.toString(16));

Functions byteToHex / swap16 defined as:

function byteToHex(byte) {
    var unsignedByte = byte & 0xff;
    if (unsignedByte < 16) {
        return ‘0’ + unsignedByte.toString(16);
    } else {
        return unsignedByte.toString(16);
    }
}

function swap16(val) {
    return ((val & 0xFF) << 8) | ((val >> 8) & 0xFF);
}

Testing it with return message = lon produces B3 09 in hex. Testing it with message = lon | lat <<8 return 96 BB 09 but result I am looking for is 96 19 B3 09 (composing lon + lat ).

Any tips? What I am doing wrong?

2

Have you tried something like this?
message = (lon<<16)|(lat<<8)

3

I solved this problem using this code:

    var long = object.long;
    var lat = object.lat;
    lat = parseInt(lat*100,10);
    var la = swap16(lat);
    la = la.toString(16);
    long = parseInt(long*100,10);
    var lon = swap16(long);
    lon = lon.toString(16);
    var header = object.header;
    var result= la;
    result+= lon;
    result= result.toString(16);
    bytes = hexToBytes(result);
  }
  }
  return bytes;

Now response is:

// encoded payload:
96 19 B3 09
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