Page History

/**
 * Parser for Lobaro Pressure Probe via LoRaWAN (hybrid gateway).
 * Usable for Pressure Probe as or with Presure+Temperature Probe.
 * Works with TTN, ChirpStack, or the Lobaro Platform.
 */
function signed(val, bits) {
    // max positive value possible for signed int with bits:
    var mx = Math.pow(2, bits-1);
    if (val < mx) {
        // is positive value, just return
        return val;
    } else {
        // is negative value, convert to neg:
        return val - (2 * mx);
    }
}

// Note that MAX_SAFE_INTEGER is 9007199254740991
function toNumber_BE(bytes, len, signed) {
    var res = 0;
    var isNeg = false;
    if (len == 0) {
        len = bytes.length;
    }
    if (signed) {
        isNeg = (bytes[0] & 0x80) != 0;
    }
 
 
    for (var i = 0; i < len ; i++) {
        if (i == 0 && isNeg) {
            // Treat most-significant bit as -2^i instead of 2^i
            res += bytes[i] & 0x7F;
            res -= 0x80;
        } else {
            res *= 256;
            res += bytes[i];
        }
    }
 
    return res;
} 
function int16_BE(bytes, idx) {
    bytes = bytes.slice(idx || 0);
    return signed(bytes[0] << 8 | bytes[1] << 0, 2*8);
}
function int32_BE(bytes, idx) {
    bytes = bytes.slice(idx || 0);
    return toNumber_BE(bytes, 4, true);
}
function uint16_BE(bytes, idx) {
    bytes = bytes.slice(idx || 0);
    return bytes[0] << 8 | bytes[1] << 0;
}
function uint32_BE(bytes, idx) {
    bytes = bytes.slice(idx || 0);
    return bytes[0] << 24 | bytes[1] << 16 | bytes[2] << 8 | bytes[3] << 0;
} 
// float32([62, 132, 168, 155]) = 0.305068
function float32(bytes, idx) {
    bytes = bytes.slice(idx || 0);
    bytes = int32_BE(bytes, 0)
    var sign = (bytes >> 31) == 0 ? 1 : -1; // Comparison with 0x80000000 fails on 32 bit systems!
    var exponent = ((bytes >> 23) & 0xFF) - 127;
    var significand = (bytes & ~(-1 << 23));
 
    if (exponent == 128) {
        // Some systems might have issues with NaN and POSITIVE_INFINITY, e.g. JSON parsing in GoLang
        // return sign * ((significand) ? Number.NaN : Number.POSITIVE_INFINITY);
		return null;
    }
 
    if (exponent == -127) {
        if (significand == 0) return sign * 0.0;
        exponent = -126;
        significand /= (1 << 22);
    } else {
      significand = (significand | (1 << 23)) / (1 << 23);
    }
 
    return sign * significand * Math.pow(2, exponent);
}
function float32_BE(bytes, idx) { return float32(bytes, idx); }
  
/**
 * TTN decoder function.
 */
function Decoder(bytes, port) {
    var vals = {};
    if( port == 20 ){
        if (bytes.length==5) {
            // Pressure Probe without temperature sensor and Bridges internal Temperature
            vals["error"] = !!(bytes[0]&0x80);
            vals["pressure"] = int16_BE(bytes, 1)/1000;
            vals["temperature"] = int16_BE(bytes, 3);
        }  else if (bytes.length==7) {
            vals["error"] = !!(bytes[0]&0x80);
            vals["pressure"] = int16_BE(bytes, 1)/1000;
            vals["temperature"] = int16_BE(bytes, 3);
            vals["voltage"] = uint16_BE(bytes, 5) / 1000;
        } else if (bytes.length==9) {
            vals["error"] = !!(bytes[0]&0x80);
            // pressure in mH2O
            vals["pressure"] = float32_BE(bytes, 1);
            // temperature in Degree Celsius
            vals["temperature"] = float32_BE(bytes, 5);
        } else if (bytes.length==11) {
            vals["error"] = !!(bytes[0]&0x80);
            // pressure in mH2O or Bar, depending on probe type
            vals["pressure"] = float32_BE(bytes, 1);
            // temperature in Degree Celsius
            vals["temperature"] = float32_BE(bytes, 5);
            vals["voltage"] = uint16_BE(bytes, 9) / 1000;
        }
    }
     
    if (port === 64 && bytes.length == 13) { // status packet
        vals["Firmware Identifier"] =  String.fromCharCode(bytes[0]) + String.fromCharCode(bytes[1]) + String.fromCharCode(bytes[2]);
        vals["FirmwareVersion"] = bytes[3] + '.' + bytes[4] + '.' + bytes[5];
        vals["status"] = bytes[6];
        vals["reboot reason"] = bytes[7];
        vals["final words"] = bytes[8];
        vals["voltage"] = uint16_BE(bytes,9)/1000.0
        vals["temperature"] =  int16_BE(bytes,11)/10.0;
    }
    return vals;
}
 
function NB_ParseModbusQuery(input){
  vals = {};
  
  for( var i = 0; i< input.d.batch.length; i++ ){
    if (input.d.batch[i].cmd == "AQMAFgAC"){
      vals["pressure"] = float32_BE(bytes(atob(input.d.batch[i].rsp)),3);
    }
    if (input.d.batch[i].cmd == "AQMAJgAC"){
      vals["temperature"] = float32_BE(bytes(atob(input.d.batch[i].rsp)),3);
    }
    
    // else: keller
    if (input.d.batch[i].cmd == "AQMAAgAC"){
      // convert to mH2O
      vals["pressure"] = float32_BE(bytes(atob(input.d.batch[i].rsp)),3)*10.197442889221;
    }
    if (input.d.batch[i].cmd == "AQMACAAC"){
      vals["temperature"] = float32_BE(bytes(atob(input.d.batch[i].rsp)),3);
    }
      // vbat
   if (input.d.batch[i].cmd == "+gQABQAB"){
      vals["vBat"] = int16_BE(bytes(atob(input.d.batch[i].rsp)),3)/1000.0;
    }
  
    // internal temperature
     if (input.d.batch[i].cmd == "+gQABAAB"){
      vals["temperatureInt"] = int16_BE(bytes(atob(input.d.batch[i].rsp)),3);
    }
  }
  
  return vals;
}
   
/**
 * TTN V3 Wrapper
 */
function decodeUplink(input) {
   return {
    data: {
      values: Decoder(input.bytes, input.fPort)
    },
    warnings: [],
    errors: []
  };
}
   
function NB_ParseDeviceQuery(input) {
  for (var key in input.d) {
      var v = input.d[key];
      switch (key) {
          case "temperature":
              v = v / 10.0;
              Device.setProperty("device.temperature", v);
              continue;
          case "vbat":
              v = v / 1000.0;
              Device.setProperty("device.voltage", v);
              continue;
      }
      Device.setProperty("device." + key, v);
  }
  return null;
}
   
function NB_ParseConfigQuery(input) {
  for (var key in input.d) {
    Device.setConfig(key, input.d[key]);
  }
    return null;
}
   
function NB_ParseStatusQuery(input) {
    NB_ParseDeviceQuery(input);
    return null;
}
   
/**
 * ChirpStack decoder function.
 */
function Decode(fPort, bytes) {
    // wrap TTN Decoder:
    return Decoder(bytes, fPort);
}
   
/**
 * Lobaro Platform decoder function.
 */
function Parse(input) {
    if (input.i && input.d) {
      // NB-IoT
      var decoded = {};
      decoded = input.d;
      decoded.address = input.i;
      decoded.fCnt = input.n;
      
      var query = input.q || "data";
      
      switch (query) {
        case "config":
          return NB_ParseConfigQuery(input);
        case "device":
          return NB_ParseDeviceQuery(input);     
        case "modbus":
          return NB_ParseModbusQuery(input);
        case "status":
          return NB_ParseStatusQuery(input);
        default:
      }
      return decoded;
    }
    
    
    var data = bytes(atob(input.data));
    var port = input.fPort;
    return Decoder(data, port);
}