//The function is :
function Decoder(bytes, port) {
// Decode an uplink message from a buffer
// (array) of bytes to an object of fields.

var latitude=0;//gps latitude,units: °
if(bytes[0] !== 0)
{
  latitude=(bytes[0]<<24 | bytes[1]<<16 | bytes[2]<<8 | bytes[3])/1000000;//gps latitude,units: °
}
else
{
  latitude=0;//gps latitude,units: °
}

var longitude = 0;
if(bytes[4] !== 0)
{
  longitude=(bytes[4]<<24 | bytes[5]<<16 | bytes[6]<<8 | bytes[7])/1000000;//gps longitude,units: °
}
else
{
 longitude=0;//gps longitude,units: °
}

var alarm=(bytes[8] & 0x40)?"TRUE":"FALSE";//Alarm status

var batV=(((bytes[8] & 0x3f) <<8) | bytes[9])/1000;//Battery,units:V

if(bytes[10] & 0xC0==0x40)
{
  var motion_mode="Move";
}
else if(bytes[10] & 0xC0 ==0x80)
{
  motion_mode="Collide";
}
else if(bytes[10] & 0xC0 ==0xC0)
{
  motion_mode="User";
}
else
{
  motion_mode="Disable";
}                                            //mode of motion

var led_updown=(bytes[10] & 0x20)?"ON":"OFF";//LED status for position,uplink and downlink

var Firmware = 160+(bytes[10] & 0x1f);  // Firmware version; 5 bits 

var roll=(bytes[11]<<8 | bytes[12])/100;//roll,units: °

var pitch=(bytes[13]<<8 | bytes[14])/100; //pitch,units: °

var hdop = 0;
if(bytes[15] > 0)
{
   hdop =bytes[15]/100; //hdop,units: °
}
else
{
   hdop =bytes[15];
}

var altitude =(bytes[16]<<8 | bytes[17]) / 100; //Altitude,units: °

return {
latitude: latitude,
longitude: longitude,
roll: roll,
pitch:pitch,
battery:batV,
ALARM_status:alarm,
MD:motion_mode,
LON:led_updown,
FW:Firmware,
HDOP:hdop,
altitude:altitude,
accuracy:3
};
}