Payload decoder adeunis field tester


function Decode( fPort, bytes )
{

// Functions
function parseCoordinate( raw_value, coordinate )

{

// This function parses a coordinate payload part into

// dmm and ddd

var raw_itude = raw_value;

var temp = "";


// Degree section

var itude_string = ( (raw_itude >> 28) & 0xF ).toString( );

raw_itude <<= 4;


itude_string += ( (raw_itude >> 28) & 0xF ).toString( );

raw_itude <<= 4;


coordinate.degrees += itude_string;

itude_string += "°";


// Minute section

temp = ( (raw_itude >> 28) & 0xF ).toString( );

raw_itude <<= 4;


temp += ( (raw_itude >> 28) & 0xF ).toString( );

raw_itude <<= 4;

itude_string += temp;

itude_string += ".";

coordinate.minutes += temp;


// Decimal section

temp = ( (raw_itude >> 28) & 0xF ).toString( );

raw_itude <<= 4;


temp += ( (raw_itude >> 28) & 0xF ).toString( );

raw_itude <<= 4;


itude_string += temp;

coordinate.minutes += ".";

coordinate.minutes += temp;

return itude_string;

}

function parseLatitude( raw_latitude, coordinate )

{

var latitude = parseCoordinate( raw_latitude, coordinate );

latitude += ((raw_latitude & 0xF0) >> 4).toString( );

coordinate.minutes += ((raw_latitude & 0xF0) >> 4).toString( );


return latitude;

}

function parseLongitude( raw_longitude, coordinate )

{

var longitude = ( ((raw_longitude >> 28) & 0xF ) ).toString( );

coordinate.degrees = longitude;

longitude += parseCoordinate( raw_longitude << 4, coordinate );


return longitude;

}

function addField( field_no, payload )

{

switch( field_no )

{

// Presence of temperature information

case 0:

payload.temperature = bytes[bytes_pos_] & 0x7F;

// Temperature is negative

if( (bytes[bytes_pos_] & 0x80) > 0 )

{

payload.temperature -= 128;

}

bytes_pos_++;

break;

// Transmission triggered by the accelerometer

case 1:

payload.trigger = "accelerometer";

break;

// Transmission triggered by pressing pushbutton 1

case 2:

payload.trigger = "pushbutton";

break;

// Presence of GPS information

case 3:

// GPS Latitude

// An object is needed to handle and parse coordinates into ddd notation

var coordinate = {};

coordinate.degrees = "";

coordinate.minutes = "";


var raw_value = 0;

raw_value |= bytes[bytes_pos_++] << 24;

raw_value |= bytes[bytes_pos_++] << 16;

raw_value |= bytes[bytes_pos_++] << 8;

raw_value |= bytes[bytes_pos_++];


payload.lati_hemisphere = (raw_value & 1) == 1 ? "South" : "North";

payload.latitude_dmm = payload.lati_hemisphere.charAt( 0 ) + " ";

payload.latitude_dmm += parseLatitude( raw_value, coordinate );

payload.latitude = ( parseFloat( coordinate.degrees ) + parseFloat( coordinate.minutes ) / 60 ) * ( (raw_value & 1) == 1 ? -1.0 : 1.0);


// GPS Longitude

coordinate.degrees = "";

coordinate.minutes = "";

raw_value = 0;

raw_value |= bytes[bytes_pos_++] << 24;

raw_value |= bytes[bytes_pos_++] << 16;

raw_value |= bytes[bytes_pos_++] << 8;

raw_value |= bytes[bytes_pos_++];


payload.long_hemisphere = (raw_value & 1) == 1 ? "West" : "East";

payload.longitude_dmm = payload.long_hemisphere.charAt( 0 ) + " ";

payload.longitude_dmm += parseLongitude( raw_value, coordinate );

payload.longitude = ( parseFloat( coordinate.degrees ) + parseFloat( coordinate.minutes ) / 60 ) * ( (raw_value & 1) == 1 ? -1.0 : 1.0);


// GPS Quality

raw_value = bytes[bytes_pos_++];


switch( (raw_value & 0xF0) >> 4 )

{

case 1:

payload.gps_quality = "Good";

break;

case 2:

payload.gps_quality = "Average";

break;

case 3:

payload.gps_quality = "Poor";

break;

default:

payload.gps_quality = (raw_value >> 4) & 0xF;

break;

}

payload.hdop = (raw_value >> 4) & 0xF;


// Number of satellites

payload.sats = raw_value & 0xF;


break;

// Presence of Uplink frame counter

case 4:

payload.ul_counter = bytes[bytes_pos_++];

break;

// Presence of Downlink frame counter

case 5:

payload.dl_counter = bytes[bytes_pos_++];

break;

// Presence of battery level information

case 6:

payload.battery_level = bytes[bytes_pos_++] << 8;

payload.battery_level |= bytes[bytes_pos_++];

break;

// Presence of RSSI and SNR information

case 7:

// RSSI

payload.rssi_dl = bytes[bytes_pos_++];

payload.rssi_dl *= -1;


// SNR

payload.snr_dl = bytes[bytes_pos_] & 0x7F;

if( (bytes[bytes_pos_] & 0x80) > 0 )

{

payload.snr_dl -= 128;

}

bytes_pos_++;

break;

default:

// Do nothing

break;

}

}


// Declaration & initialization

var status_ = bytes[0];

var bytes_len_ = bytes.length;

var bytes_pos_ = 1;

var i = 0;

var payload = {};


// Get raw payload

var temp_hex_str = ""

payload.payload = "";

for( var j = 0; j < bytes_len_; j++ )

{

temp_hex_str = bytes[j].toString( 16 ).toUpperCase( );

if( temp_hex_str.length == 1 )

{

temp_hex_str = "0" + temp_hex_str;

}

payload.payload += temp_hex_str;

}


// Get payload values

do

{

// Check status, whether a field is set

if( (status_ & 0x80) > 0 )

{

addField( i, payload );

}

i++;

}

while( ((status_ <<= 1) & 0xFF) > 0 );


return payload;

}
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