decoder.js

function get_num(x, min, max, precision, round) {
  
	var range = max - min;
	var new_range = (Math.pow(2, precision) - 1) / range;
	var back_x = x / new_range;
	
	if (back_x===0) {
		back_x = min;
	}
	else if (back_x === (max - min)) {
		back_x = max;
	}
	else {
		back_x += min;
	}
	return Math.round(back_x*Math.pow(10,round))/Math.pow(10,round);
}

function Decoder(bytes) {

    var decoded = {};

    var resetCause_dict = {
        0:"POWERON",
        1:"EXTERNAL",
        2:"SOFTWARE",
        3:"WATCHDOG",
        4:"FIREWALL",
        5:"OTHER",
        6:"STANDBY"
    };

    // settings
    if (port === 3){
        decoded.system_status_interval = (bytes[1] << 8) | bytes[0];

        decoded.system_functions = {};//bytes[2];
        decoded.system_functions.gps_periodic =  ((bytes[2] >> 0)&0x01)? 1 : 0;
        decoded.system_functions.gps_triggered =  ((bytes[2] >> 1)&0x01)? 1 : 0;
        decoded.system_functions.gps_hot_fix =  ((bytes[2] >> 2)&0x01)? 1 : 0;
        decoded.system_functions.accelerometer_enabled =  ((bytes[2] >> 3)&0x01)? 1 : 0;
        decoded.system_functions.light_enabled =  ((bytes[2] >> 4)&0x01)? 1 : 0;
        decoded.system_functions.temperature_enabled =  ((bytes[2] >> 5)&0x01)? 1 : 0;
        decoded.system_functions.humidity_enabled =  ((bytes[2] >> 6)&0x01)? 1 : 0;
        decoded.system_functions.pressure_enabled =  ((bytes[2] >> 7)&0x01)? 1 : 0;

        decoded.lorawan_datarate_adr = {};//bytes[3];
        decoded.lorawan_datarate_adr.datarate = bytes[3]&0x0f;
        decoded.lorawan_datarate_adr.confirmed_uplink =  ((bytes[3] >> 6)&0x01)? 1 : 0;
        decoded.lorawan_datarate_adr.adr =  ((bytes[3] >> 7)&0x01)? 1 : 0;

        decoded.sensor_interval = (bytes[5] << 8) | bytes[4];
        decoded.gps_cold_fix_timeout = (bytes[7] << 8) | bytes[6];
        decoded.gps_hot_fix_timeout = (bytes[9] << 8) | bytes[8];
        decoded.gps_minimal_ehpe = bytes[10];
        decoded.mode_slow_voltage_threshold = bytes[11];
    }
    else if (port === 2){
        decoded.resetCause = resetCause_dict[bytes[0]];
        decoded.mode = bytes[1];
        decoded.battery = get_num(bytes[2],0,100,8,1);
        decoded.temperature = get_num(bytes[3],-20,80,8,1);
        decoded.vbus = get_num(bytes[4],0,3.6,8,2);
        decoded.system_functions_errors = bytes[5].toString(2);
      }
    else if (port === 1){
        decoded.temperature = get_num(((bytes[1] << 8) | bytes[0]),-20,80,16,2);
        decoded.pressure = get_num(((bytes[3] << 8) | bytes[2]),8000,12000,16,2);
        decoded.status = bytes[4];
        decoded.humidity = get_num(bytes[5],0,100,8,1);
        decoded.accelerometer = get_num(bytes[6],-100,100,8,2);
      }

    return decoded;
  }