EMU - Professional II

/**
* MIT License
* Copyright (c) 2021 EMU Electronic AG (https://www.emuag.ch/). All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/

/**
 * decodeUplink is called by TheThingsNetwork
 * we use our parsePayload() for decoding
 * 
 * @param {*} input 
 * @returns object containing decoded payload
 * {
 *      "Active Energy Export T1": {
 *        "unit": "Wh",
 *        "value": 0
 *      },
 *      "Active Energy Export T2": {
 *        "unit": "Wh",
 *        "value": 0
 *      },
 *      "Active Energy Import T1": {
 *        "unit": "Wh",
 *        "value": 4000
 *      },
 *      "Active Energy Import T2": {
 *        "unit": "Wh",
 *        "value": 0
 *      },
 *      "Reactive Energy Export T1": {
 *        "unit": "varh",
 *        "value": 0
 *      },
 *      "Reactive Energy Export T2": {
 *        "unit": "varh",
 *        "value": 0
 *      },
 *      "Reactive Energy Import T1": {
 *        "unit": "varh",
 *        "value": 0
 *      },
 *      "Reactive Energy Import T2": {
 *        "unit": "varh",
 *        "value": 0
 *      },
 *      "medium": {
 *        "desc": "Electricity",
 *        "type": 1
 *      },
 *      "readoutInterval": 900,
 *      "timeStamp": 1635499020,
 *      "timestamp": {
 *        "unit": "seconds",
 *        "value": 1635499020
 *      }
 */
function decodeUplink(input) {
    data = input.bytes;
    //uplink with only 2 bytes is only status update, ignore it 
    if(data.length<=2){
        return {};
    }
    
    var obj = {};
    
    
    //check CRC-8 which resides at the end
    crc8Received = data[data.length - 1];
    dataToCheck = [];
    for(var i = 0; i < data.length - 1; i++){
        dataToCheck.push(data[i]);
    }
    
    if (crc8_encode(dataToCheck).toString(16) === crc8Received.toString(16)) {
        //crc-8 seems ok, 
    } else {
        obj.warnings = ['crc-8 wrong'];
        //perhaps decide to stop further processing if crc-8 is wrong
    } 
    
    //first 4 bytes are allways the timestamp, this is the timestamp from the datalogger
    var timeStamp = getUint32(data);
    
    obj.data = parsePayload(data);

    //for TTN we strip unused information
    for(var property in obj.data){
        delete obj.data[property].cfgdescription;
        delete obj.data[property].cfgtariff;
        delete obj.data[property].cfgunit;
        delete obj.data[property].cfgorder;
        delete obj.data[property].order;
    }

    obj.data.timeStamp = timeStamp;
    obj.data.medium = {
        "type": 1,
        "desc": "Electricity"
    };
         
    return obj;
}

/**
 * Decode is called by Chirpstack
 * @param {*} fPort 
 * @param {*} data 
 * @param {*} variables 
 * @returns object containing decoded payload
 * 
 * {
 *  "Active Energy Import T1": {
 *     "unit": "Wh",
 *     "cfgdescription": 3,
 *     "cfgunit": 1,
 *     "cfgtariff": 1,
 *     "order": 3,
 *     "value": 1809
 *  },
 *  "Active Energy Import T2": {
 *     "unit": "Wh",
 *     "cfgdescription": 3,
 *     "cfgunit": 1,
 *     "cfgtariff": 2,
 *     "order": 4,
 *     "value": 128
 *  },
 *  "Active Energy Export T1": {
 *     "unit": "Wh",
 *     "cfgdescription": 5,
 *     "cfgunit": 1,
 *     "cfgtariff": 1,
 *     "order": 5,
 *     "value": 1149
 *  },
 *  "Active Energy Export T2": {
 *     "unit": "Wh",
 *     "cfgdescription": 5,
 *     "cfgunit": 1,
 *     "cfgtariff": 2,
 *     "order": 6,
 *     "value": 17794
 *  },
 *  "Reactive Energy Import T1": {
 *     "unit": "varh",
 *     "cfgdescription": 10,
 *     "cfgunit": 5,
 *     "cfgtariff": 1,
 *     "order": 7,
 *     "value": 1864
 *  },
 *  "Reactive Energy Import T2": {
 *     "unit": "varh",
 *     "cfgdescription": 10,
 *     "cfgunit": 5,
 *     "cfgtariff": 2,
 *     "order": 8,
 *     "value": 2600
 *  },
 *  "Reactive Energy Export T1": {
 *     "unit": "varh",
 *     "cfgdescription": 13,
 *     "cfgunit": 5,
 *     "cfgtariff": 1,
 *     "order": 9,
 *     "value": 338
 *  },
 *  "Reactive Energy Export T2": {
 *     "unit": "varh",
 *     "cfgdescription": 13,
 *     "cfgunit": 5,
 *     "cfgtariff": 2,
 *     "order": 10,
 *     "value": 9661
 *  },
 *  "timeStamp": 1635499800,
 *  "medium": {
 *     "type": 1,
 *     "desc": "Electricity"
 *  },
 *  "readoutInterval": 900
 * }
 */
function Decode(fPort, data, variables) {
    //uplink with only 2 bytes is only status update, ignore it 
    if (data.length <= 2) {
        return {};
    }
    
    var obj = {};
    
    //check CRC-8 which resides at the end
    crc8Received = data[data.length - 1];
    dataToCheck = [];
    for(var i = 0; i < data.length - 1; i++){
        dataToCheck.push(data[i]);
    }
    
    if (crc8_encode(dataToCheck).toString(16) === crc8Received.toString(16)) {
        //crc-8 seems ok, 
    } else {
        obj.warnings = ['crc-8 wrong'];
        //perhaps decide to stop further processing if crc-8 is wrong
    } 
    
    //first 4 bytes are allways the timestamp, this is the timestamp from the datalogger
    var timeStamp = getUint32(data);
    obj = parsePayload(data);
    obj.timeStamp = timeStamp;

 
    //add a human readable timestamp to the payload
    var meterDate = new Date(timeStamp * 1000);
    var  options = { timeZone:'Europe/Berlin', weekday: 'short', year: 'numeric', month: 'short', day: 'numeric', hour:'numeric', minute:'numeric', second:'numeric'};
    obj.timeStampReadable = meterDate.toLocaleString('de-CH',options);

    
    obj.medium = {
        "type": 1,
        "desc": "Electricity"
    };
    
    //Default readout-interval is allways 15 minutes
    obj.readoutInterval = (15 * 60); //15 Min * 60 Sec
    //you can overwrite the readout-interval when defining variables for this meter
    if(variables !== null && variables.readoutInterval !== null){
         obj.readoutInterval = variables.readoutInterval;
    }
    
    return obj;
}


/**
 * encodeDownlink is called by TheThingsNetwork
 * @param {*} data Object containing configuration
 * @returns binary data 
 */
function encodeDownlink(data){
/**
 * Example JSON-Object for Timestamp, Energy 0x03-0x0A 
 * {
 *   "fPort": 1,
 *   "timeInterval": 15,
 *   "sndAck": true,
 *   "startReJoin": false,
 *   "portIsActive": true,
 *   "values": [
 *       1,
 *       3,
 *       4,
 *       5,
 *       6,
 *       7,
 *       8,
 *       9,
 *       10
 *   ]
 * } 
 * 
 */
    //fPort must be defined else define it
    if (data.data.fPort === null || data.data.fPort === undefined){
        data.data.fPort = 1;
    }
    fPort = data.data.fPort;
    bytes = [];

    //just call the Encode function 
    bytes = Encode(fPort, data.data, {});
         
    return {fPort: fPort, bytes: bytes};
}

/**
 * decodeDownlink is used by TheThingsNetwork
 * @param {*} input  binary data containing configuration
 * @returns data object containing decoded configuration
 */
function decodeDownlink(input) {
    var data = {};
    data.fPort = input.fPort;
    if(input.bytes.length > 3){
        var i = 0;
        data.timeInterval = Number(getInt16([input.bytes[i++], input.bytes[i++]]));
        configFlag = input.bytes[i++];
        //sndAck activated ?
        if (configFlag & 0x02) {
            data.sndAck = true;
        }
        else {
            data.sndAck = false;
        }
        //start a rejoin after receiving this uplink ?
        if (configFlag & 0x04) {
            data.startReJoin = true;
        }
        else {
            data.startReJoin = false;
        }
        //is this uplink on this port activated ?
        if (configFlag & 0x08) {
            data.portIsActive = true;
        }
        else {
            data.portIsActive = false;
        }
        data.values = []
        for (i; i < input.bytes.length - 1; ++i) {
            data.values.push(Number(getUint8(input.bytes[i])));
        }
    }
    return data;
}
/**
 * Encode is called by Chirpstack
 * @param {*} fPort 
 * @param {*} data Object containing configuration
 * @param {*} variables 
 * @returns binary data
 */
function Encode(fPort, data, variables) {
/**
 * Example JSON-Object for Timestamp, Energy 0x03-0x0A 
 * {
 *   "fPort": 1,
 *   "timeInterval": 15,
 *   "sndAck": true,
 *   "startReJoin": false,
 *   "portIsActive": true,
 *   "values": [
 *       1,
 *       3,
 *       4,
 *       5,
 *       6,
 *       7,
 *       8,
 *       9,
 *       10
 *   ]
 * } 
 * 
 */    
    bytes = [];
    
    //make sure the time is valid and between 1 and 65535!
    data.timeInterval = Math.min(data.timeInterval, 0xFFFF);
    data.timeInterval = Math.max(data.timeInterval,1 );
    
    //push second byte to first position
    bytes.push(data.timeInterval & 0X00FF);
    //push first byte to second pposition
    bytes.push(data.timeInterval >> 8);
    
    var configFlags = 0x00;
    //Send Acknowledge for each Uplink back
    if (data.sndAck) {
        configFlags |= 0x02;
    }
    //Start Re-Join
    if (data.startReJoin) {
        configFlags |= 0x04;
    }
    //Enable this port so it sends data
    if (data.portIsActive) {
        configFlags |= 0x08;
    }
    
    //Push the config flag on the stack
    bytes.push(configFlags);
    for(var i=0; i< data.values.length; i++) {
        bytes.push(data.values[i]);
    }
    //apply crc-8
    crc8 = crc8_encode(bytes);
    bytes.push(crc8);
    
    return bytes;
}


 

/**
* read 1 byte of data an convert it to an Uint8
* @param {*} data 
* @returns 
*/
function getUint8(data) {
    var value = data >>> 0;
    return value;
    
}

function flip(n) {
    var x = [];
    n = Number(n);
    //will work only for positive numbers
    var single = n.toString(2).split("");
    for(var i = 0; i<single.length; i++){
        x.push(single[i] == 1 ? 0 : 1);
    }
    
    var tmp = x.join("");
    var y = (parseInt(tmp, 2) + 1) * -1;
    return y;
}


/**
* read 1 byte of data an convert it to an Int8
* @param {*} data 
* @returns 
*/
function getInt8(data) {
    
    if(data === 0){return 0;}
    if(data >> 7 == 1){
        return flip(data);
    }
    var value = data >>> 0;
    return value;
}
/**
* read 2 bytes of data an convert it to an Int16
* @param {*} data 
* @returns 
*/
function getInt16(data) {
    
    value = (data[1] << 8 | data[0]);
    return value;
    
}
/**
* read 2 bytes of data an convert it to an Uint16
* @param {*} data 
* @returns 
*/
function getUint16(data) {
    value = (data[1] << 8 | data[0]) >>> 0;
    return value;
    
    
}
/**
* read 4 bytes of data an convert it to an Int32
* @param {*} data 
* @returns 
*/
function getInt32(data) {
    value = (data[3] << 24 | data[2] << 16 | data[1] << 8 | data[0]);
    return value;
    
    
    
}
/**
* * read 4 bytes of data an convert it to an Uint32
* @param {*} data 
* @returns 
*/
function getUint32(data) {
    
    value = (data[3] << 24 | data[2] << 16 | data[1] << 8 | data[0]) >>> 0;
    return value;
}



/**
* read 8 bytes of data an convert it to an Int64
* @param {*} data 
* @returns 
*/
function getInt64(data) {
    //JS can't handle bitwise operation with more than 32bit !
    //so this won't work 
    //if Chirpstack will use another javascript engine we could use typearray's
    var value = Number((data[7] << 56 | data[6] << 48 | data[5] << 40 | data[4] << 32 | data[3] << 24 | data[2] << 16 | data[1] << 8 | data[0]));
    return value;
    
}
/**
* * read 8 bytes of data an convert it to an Uint32
* @param {*} data 
* @returns 
*/
function getUint64(data) {
    //JS can't handle bitwise operation with more than 32bit !
    //so this won't work 
    //if Chirpstack will use another javascript engine we could use typearray's
    
    value = Number((data[7] << 56 | data[6] << 48 | data[5] << 40 | data[4] << 32 | data[3] << 24 | data[2] << 16 | data[1] << 8 | data[0]) >>> 0);
    return value;
    
}

function getBCD(data) {
    var bcd = "";
    for(var i=0; i< data.length; i++) {
        bcd = bcd + "" + data[i];
        
    }
    
    return bcd;
}


function getASCII(data) {
    var ascii = "";
    
    for(var i=0; i< data.length; i++) {
        entry = getUint8(data[i]);
        if (entry != 0x00) {
            ascii = ascii + String.fromCharCode(entry.toString());
        }
    }
    return ascii;
}
/**
* parses the variable data and returns an object
* 
* a value is identified by its id
* 
* @param {*} obj 
* @param {*} data 
*/
function parsePayload(data){
    var dataTypes = [];
    
    //be sure to fill the complete array
    //if we receive an invalid datatype we skip the rest of the data 
    for (i = 0; i < 256; i++) {
        dataTypes[i] = {'len': 255,'description': 'invalid data-type'};
    }
    
    //the "order" is assigned according to the entry
dataTypes[0x00]={'len':4,'description':'data-logger-index','dataType':'Uint32'};
dataTypes[0x01]={'len':4,'description':'timestamp','dataType':'Uint32','unit':'seconds'};
dataTypes[0x02]={'len':4,'description':'timestamp-previous','dataType':'Uint32','unit':'seconds'};
dataTypes[0x03]={'len':4,'description':'ActiveEnergyImportT1','dataType':'Uint32','unit':'Wh','cfgdescription':3,"cfgunit":1,'cfgtariff':1};
dataTypes[0x04]={'len':4,'description':'ActiveEnergyImportT2','dataType':'Uint32','unit':'Wh','cfgdescription':3,"cfgunit":1,'cfgtariff':2};
dataTypes[0x05]={'len':4,'description':'ActiveEnergyExportT1','dataType':'Uint32','unit':'Wh','cfgdescription':5,"cfgunit":1,'cfgtariff':1};
dataTypes[0x06]={'len':4,'description':'ActiveEnergyExportT2','dataType':'Uint32','unit':'Wh','cfgdescription':5,"cfgunit":1,'cfgtariff':2};
dataTypes[0x07]={'len':4,'description':'ReactiveEnergyImportT1','dataType':'Uint32','unit':'varh','cfgdescription':10,"cfgunit":5,'cfgtariff':1};
dataTypes[0x08]={'len':4,'description':'ReactiveEnergyImportT2','dataType':'Uint32','unit':'varh','cfgdescription':10,"cfgunit":5,'cfgtariff':2};
dataTypes[0x09]={'len':4,'description':'ReactiveEnergyExportT1','dataType':'Uint32','unit':'varh','cfgdescription':13,"cfgunit":5,'cfgtariff':1};
dataTypes[0x0A]={'len':4,'description':'ReactiveEnergyExportT2','dataType':'Uint32','unit':'varh','cfgdescription':13,"cfgunit":5,'cfgtariff':2};
dataTypes[0x0B]={'len':4,'description':'ActivePowerL123','dataType':'Int32','unit':'W','cfgdescription':25,"cfgunit":13};
dataTypes[0x0C]={'len':4,'description':'ActivePowerL1','dataType':'Int32','unit':'W','cfgdescription':25,"cfgunit":13,'cfgphase':1};
dataTypes[0x0D]={'len':4,'description':'ActivePowerL2','dataType':'Int32','unit':'W','cfgdescription':25,"cfgunit":13,'cfgphase':2};
dataTypes[0x0E]={'len':4,'description':'ActivePowerL3','dataType':'Int32','unit':'W','cfgdescription':25,"cfgunit":13,'cfgphase':3};
dataTypes[0x0F]={'len':4,'description':'CurrentL123','dataType':'Int32','unit':'mA','cfgdescription':31,"cfgunit":28};
dataTypes[0x10]={'len':4,'description':'CurrentL1','dataType':'Int32','unit':'mA','cfgdescription':31,"cfgunit":28,'cfgphase':1};
dataTypes[0x11]={'len':4,'description':'CurrentL2','dataType':'Int32','unit':'mA','cfgdescription':31,"cfgunit":28,'cfgphase':2};
dataTypes[0x12]={'len':4,'description':'CurrentL3','dataType':'Int32','unit':'mA','cfgdescription':31,"cfgunit":28,'cfgphase':3};
dataTypes[0x13]={'len':4,'description':'CurrentN','dataType':'Int32','unit':'mA','cfgdescription':31,"cfgunit":28,'cfgphase':4};
dataTypes[0x14]={'len':4,'description':'VoltageL1-N','dataType':'Int32','unit':'V/10','unit_calculated':'V','factor':0.1,'fixed':1,'cfgdescription':30,"cfgunit":26,'cfgphase':1};
dataTypes[0x15]={'len':4,'description':'VoltageL2-N','dataType':'Int32','unit':'V/10','unit_calculated':'V','factor':0.1,'fixed':1,'cfgdescription':30,"cfgunit":26,'cfgphase':2};
dataTypes[0x16]={'len':4,'description':'VoltageL3-N','dataType':'Int32','unit':'V/10','unit_calculated':'V','factor':0.1,'fixed':1,'cfgdescription':30,"cfgunit":26,'cfgphase':3};
dataTypes[0x17]={'len':1,'description':'PowerfactorL1','dataType':'Int8','unit':'Cos','factor':0.01,'fixed':2,'cfgdescription':32,"cfgunit":31,'cfgphase':1};
dataTypes[0x18]={'len':1,'description':'PowerfactorL2','dataType':'Int8','unit':'Cos','factor':0.01,'fixed':2,'cfgdescription':32,"cfgunit":31,'cfgphase':2};
dataTypes[0x19]={'len':1,'description':'PowerfactorL3','dataType':'Int8','unit':'Cos','factor':0.01,'fixed':2,'cfgdescription':32,"cfgunit":31,'cfgphase':3};
dataTypes[0x1A]={'len':2,'description':'Frequency','dataType':'Int16','unit':'Hz','factor':0.1,'fixed':1,'cfgdescription':33,"cfgunit":32};
dataTypes[0x1B]={'len':4,'description':'ActivePoweraverage','dataType':'Int32','unit':'W',"cfgunit":13,};
dataTypes[0x1C]={'len':4,'description':'ActiveEnergyImportT1kWh','dataType':'Uint32','unit':'kWh','cfgdescription':3,"cfgunit":2,'cfgtariff':1};
dataTypes[0x1D]={'len':4,'description':'ActiveEnergyImportT2kWh','dataType':'Uint32','unit':'kWh','cfgdescription':3,"cfgunit":2,'cfgtariff':2};
dataTypes[0x1E]={'len':4,'description':'ActiveEnergyExportT1kWh','dataType':'Uint32','unit':'kWh','cfgdescription':5,"cfgunit":2,'cfgtariff':1};
dataTypes[0x1F]={'len':4,'description':'ActiveEnergyExportT2kWh','dataType':'Uint32','unit':'kWh','cfgdescription':5,"cfgunit":2,'cfgtariff':2};
dataTypes[0x20]={'len':4,'description':'ReactiveEnergyImportT1kvarh','dataType':'Uint32','unit':'kvarh','cfgdescription':10,"cfgunit":6,'cfgtariff':1};
dataTypes[0x21]={'len':4,'description':'ReactiveEnergyImportT2kvarh','dataType':'Uint32','unit':'kvarh','cfgdescription':10,"cfgunit":6,'cfgtariff':2};
dataTypes[0x22]={'len':4,'description':'ReactiveEnergyExportT1kvarh','dataType':'Uint32','unit':'kvarh','cfgdescription':13,"cfgunit":6,'cfgtariff':1};
dataTypes[0x23]={'len':4,'description':'ReactiveEnergyExportT2kvarh','dataType':'Uint32','unit':'kvarh','cfgdescription':13,"cfgunit":6,'cfgtariff':2};
dataTypes[0x24]={'len':8,'description':'ActiveEnergyImportT164bit','dataType':'uInt64','unit':'Wh','cfgdescription':3,"cfgunit":1,'cfgtariff':1};
dataTypes[0x25]={'len':8,'description':'ActiveEnergyImportT264bit','dataType':'uInt64','unit':'Wh','cfgdescription':3,"cfgunit":1,'cfgtariff':2};
dataTypes[0x26]={'len':8,'description':'ActiveEnergyExportT164bit','dataType':'uInt64','unit':'Wh','cfgdescription':5,"cfgunit":1,'cfgtariff':1};
dataTypes[0x27]={'len':8,'description':'ActiveEnergyExportT264bit','dataType':'uInt64','unit':'Wh','cfgdescription':5,"cfgunit":1,'cfgtariff':2};
dataTypes[0x28]={'len':8,'description':'ReactiveEnergyImportT164bit','dataType':'uInt64','unit':'varh','cfgdescription':10,"cfgunit":5,'cfgtariff':1};
dataTypes[0x29]={'len':8,'description':'ReactiveEnergyImportT264bit','dataType':'uInt64','unit':'varh','cfgdescription':10,"cfgunit":5,'cfgtariff':2};
dataTypes[0x2A]={'len':8,'description':'ReactiveEnergyExportT164bit','dataType':'uInt64','unit':'varh','cfgdescription':13,"cfgunit":5,'cfgtariff':1};
dataTypes[0x2B]={'len':8,'description':'ReactiveEnergyExportT264bit','dataType':'uInt64','unit':'varh','cfgdescription':13,"cfgunit":5,'cfgtariff':2};
dataTypes[0xF0]={'len':1,'description':'errorcode','dataType':'ErrorCode'};
dataTypes[0xF1]={'len':4,'description':'serial-number','dataType':'MeterSerial'};
dataTypes[0xF2]={'len':4,'description':'factor-number','dataType':'MeterSerial'};
dataTypes[0xF3]={'len':2,'description':'current-transformerprimary','dataType':'Uint16',"cfgunit":72,};
dataTypes[0xF4]={'len':2,'description':'current-transformersecondary','dataType':'Uint16',"cfgunit":72,};
dataTypes[0xF5]={'len':2,'description':'voltage-transformerprimary','dataType':'Uint16',"cfgunit":72,};
dataTypes[0xF6]={'len':2,'description':'voltage-transformersecondary','dataType':'Uint16',"cfgunit":72,};
dataTypes[0xF7]={'len':1,'description':'meter-typ','dataType':'Uint8'};
dataTypes[0xF8]={'len':4,'description':'MIDyear','dataType':'BCD',};
dataTypes[0xF9]={'len':4,'description':'factoryyear','dataType':'BCD',};
dataTypes[0xFA]={'len':4,'description':'firmwareversion','dataType':'ASCII'};
dataTypes[0xFB]={'len':4,'description':'mid-Version','dataType':'ASCII'};
dataTypes[0xFC]={'len':4,'description':'manufacturer','dataType':'ASCII'};
dataTypes[0xFD]={'len':4,'description':'hw-index','dataType':'ASCII'};
dataTypes[0xFE]={'len':4,'description':'systemtime','dataType':'Uint32'};
    
    
    var obj = {};
    
    var i = 4; //the first 4 bytes is allways the timestamp
    //the last byte is the crc-code so ignore this one
    while (i < (data.length - 1)) {
        //extract signature byte 
        indexOfDataType = data[i];
        dataType = dataTypes[indexOfDataType];
        i++;
        //also save the sort-order value  
        dataType.order = indexOfDataType;
        
        switch (dataType.dataType) {
            case 'Int8':
            dataType.value = Number(getInt8([data[i++]]));
            break;
            case 'Uint8':
            dataType.value = Number(getUint8([data[i++]]));
            break;
            case 'Int16':
            dataType.value = Number(getInt16([data[i++], data[i++]]));
            break;
            case 'Uint16':
            dataType.value = Number(getUint16([data[i++], data[i++]]));
            break;
            case 'Uint32':
            dataType.value = Number(getUint32([data[i++], data[i++], data[i++], data[i++]]));
            break;
            case 'Int32':
            dataType.value = Number(getInt32([data[i++], data[i++], data[i++], data[i++]]));
            break;
            case 'uInt64':
            dataType.value = Number(getUint64([data[i++], data[i++], data[i++], data[i++], data[i++], data[i++], data[i++], data[i++]]));
            break;
            case 'Int64':
            dataType.value = Number(getInt64([data[i++], data[i++], data[i++], data[i++], data[i++], data[i++], data[i++], data[i++]]));
            break;
            case 'MeterSerial':

                dataType.value = ('0' + Number(getUint8([data[i++]])).toString(16)).slice(-2);
                dataType.value = ('0' + Number(getUint8([data[i++]])).toString(16)).slice(-2) + dataType.value;
                dataType.value = ('0' + Number(getUint8([data[i++]])).toString(16)).slice(-2) + dataType.value;
                dataType.value = ('0' + Number(getUint8([data[i++]])).toString(16)).slice(-2) + dataType.value;

            break;
            case 'BCD':
            dataType.value = getBCD([data[i++], data[i++], data[i++], data[i++]]);
            break;
            case 'ASCII':
            dataType.value = getASCII([data[i++], data[i++], data[i++], data[i++]]);
            break;
            case 'ErrorCode':
            dataType.value =  Number(getUint8([data[i++]]));
            //also encode the error
            dataType.TimeChanged =  dataType.value & 0x01 ? true : false;
            dataType.CTRatioChange =  dataType.value & 0x02 ? true : false;
            dataType.VTRatioChange =  dataType.value & 0x04 ? true : false;
            dataType.ImpulseWidthChange =  dataType.value & 0x08 ? true : false;
            dataType.ImpulseRatioChange =  dataType.value & 0x10 ? true : false;
            dataType.PowerFail =  dataType.value & 0x20 ? true : false;
            dataType.LogbookFull = dataType.value & 0x80 ? true : false;
            
            break;
            default:
            break;
            
        }
        //if we have a factor apply it but keep the old value
        if (dataType.factor && !isNaN(dataType.factor)) {
            var fixed = 0;
            if (dataType.fixed && !isNaN(dataType.fixed)) {
                fixed = dataType.fixed;
            }
            //save the value which was sent by the meter (perhaps needed later)
            dataType.value_raw = dataType.value;
            //calculate the new value using the factor
            dataType.value = Number((dataType.value * dataType.factor).toFixed(fixed));
        }
        
        obj[dataType.description] = dataType;
        //remove all unused infos like dataType, description, len
        delete dataType.len;
        delete dataType.description;
        delete dataType.dataType;
        delete dataType.factor;
        delete dataType.fixed;
    }
    
    return obj;
    
    
}
function crc8_encode(data) {
    
    var xorOut = 0x0000;
    var table = [
        0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B,
        0x12, 0x15, 0x38, 0x3F, 0x36, 0x31,
        0x24, 0x23, 0x2A, 0x2D, 0x70, 0x77,
        0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
        0x48, 0x4F, 0x46, 0x41, 0x54, 0x53,
        0x5A, 0x5D, 0xE0, 0xE7, 0xEE, 0xE9,
        0xFC, 0xFB, 0xF2, 0xF5, 0xD8, 0xDF,
        0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
        0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B,
        0x82, 0x85, 0xA8, 0xAF, 0xA6, 0xA1,
        0xB4, 0xB3, 0xBA, 0xBD, 0xC7, 0xC0,
        0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
        0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4,
        0xED, 0xEA, 0xB7, 0xB0, 0xB9, 0xBE,
        0xAB, 0xAC, 0xA5, 0xA2, 0x8F, 0x88,
        0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
        0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C,
        0x35, 0x32, 0x1F, 0x18, 0x11, 0x16,
        0x03, 0x04, 0x0D, 0x0A, 0x57, 0x50,
        0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
        0x6F, 0x68, 0x61, 0x66, 0x73, 0x74,
        0x7D, 0x7A, 0x89, 0x8E, 0x87, 0x80,
        0x95, 0x92, 0x9B, 0x9C, 0xB1, 0xB6,
        0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
        0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2,
        0xEB, 0xEC, 0xC1, 0xC6, 0xCF, 0xC8,
        0xDD, 0xDA, 0xD3, 0xD4, 0x69, 0x6E,
        0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
        0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A,
        0x43, 0x44, 0x19, 0x1E, 0x17, 0x10,
        0x05, 0x02, 0x0B, 0x0C, 0x21, 0x26,
        0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
        0x4E, 0x49, 0x40, 0x47, 0x52, 0x55,
        0x5C, 0x5B, 0x76, 0x71, 0x78, 0x7F,
        0x6A, 0x6D, 0x64, 0x63, 0x3E, 0x39,
        0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
        0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D,
        0x14, 0x13, 0xAE, 0xA9, 0xA0, 0xA7,
        0xB2, 0xB5, 0xBC, 0xBB, 0x96, 0x91,
        0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
        0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5,
        0xCC, 0xCB, 0xE6, 0xE1, 0xE8, 0xEF,
        0xFA, 0xFD, 0xF4, 0xF3
    ];
    var crc = 0x0000;
    for (var j = 0; j < data.length; j++) {
        crc = table[crc ^ data[j]];
    }
    return (crc ^ xorOut) & 0xFFFF;
    
}

/**
 * Simplified TTN Decoder - Extract Active Energy Import T1 (register 0x03 in Wh or 0x1C in kWh) and return it as kWh
 */
function decodeUplink(input) {
    var data = input.bytes;
    
    // Uplink with only 2 bytes is status update, ignore it
    if (data.length <= 2) {
        return {
            data: {},
            warnings: ["Payload too short"]
        };
    }
    
    // Check CRC-8 (last byte)
    var crc8Received = data[data.length - 1];
    var dataToCheck = data.slice(0, -1);
    
    if (crc8_encode(dataToCheck) !== crc8Received) {
        return {
            data: {},
            warnings: ["CRC-8 validation failed"]
        };
    }
    
    // Search for Active Energy Import T1 kWh (ID: 0x1C) or Wh (ID: 0x03)
    var energy_kWh = null;
    var i = 4; // Skip first 4 bytes (timestamp)
    
    while (i < data.length - 1) { // Stop before CRC byte
        var dataTypeId = data[i];
        i++;
        
        if (dataTypeId === 0x1C) {
            // Found Active Energy Import T1 in kWh (4 bytes, Uint32)
            energy_kWh = getUint32(data.slice(i, i + 4));
            break;
        } else if (dataTypeId === 0x03) {
            // Found Active Energy Import T1 in Wh (4 bytes, Uint32)
            var energy_Wh = getUint32(data.slice(i, i + 4));
            energy_kWh = energy_Wh / 1000;
            break;
        } else {
            // Skip this value based on known lengths
            var length = getDataTypeLength(dataTypeId);
            if (length === 255) break; // Invalid data type
            i += length;
        }
    }
    
    // Return result
    if (energy_kWh !== null) {
        return {
            data: {
                energy_kWh_inc: energy_kWh,
                timestamp: getUint32(data.slice(0, 4))   // Datenlogger-Zeit, Unix-Sekunden UTC
            }
        };
    } else {
        return {
            data: {},
            warnings: ["Active Energy Import T1 not found in payload"]
        };
    }
}

/**
 * Get data type length for skipping unknown values
 */
function getDataTypeLength(id) {
    var lengths = {
        0x00: 4, 0x01: 4, 0x02: 4, 0x03: 4, 0x04: 4, 0x05: 4, 
        0x06: 4, 0x07: 4, 0x08: 4, 0x09: 4, 0x0A: 4, 0x0B: 4,
        0x0C: 4, 0x0D: 4, 0x0E: 4, 0x0F: 4, 0x10: 4, 0x11: 4,
        0x12: 4, 0x13: 4, 0x14: 4, 0x15: 4, 0x16: 4, 0x17: 1,
        0x18: 1, 0x19: 1, 0x1A: 2, 0x1B: 4, 0x1C: 4, 0x1D: 4,
        0x1E: 4, 0x1F: 4, 0x20: 4, 0x21: 4, 0x22: 4, 0x23: 4,
        0x24: 8, 0x25: 8, 0x26: 8, 0x27: 8, 0x28: 8, 0x29: 8,
        0x2A: 8, 0x2B: 8, 0xF0: 1, 0xF1: 4, 0xF2: 4, 0xF3: 2,
        0xF4: 2, 0xF5: 2, 0xF6: 2, 0xF7: 1, 0xF8: 4, 0xF9: 4,
        0xFA: 4, 0xFB: 4, 0xFC: 4, 0xFD: 4, 0xFE: 4
    };
    return lengths[id] || 255;
}

/**
 * Read 4 bytes as Uint32 (little-endian)
 */
function getUint32(data) {
    return (data[3] << 24 | data[2] << 16 | data[1] << 8 | data[0]) >>> 0;
}

/**
 * CRC-8 calculation
 */
function crc8_encode(data) {
    var table = [
        0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15, 0x38, 0x3F, 0x36, 0x31,
        0x24, 0x23, 0x2A, 0x2D, 0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
        0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D, 0xE0, 0xE7, 0xEE, 0xE9,
        0xFC, 0xFB, 0xF2, 0xF5, 0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
        0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85, 0xA8, 0xAF, 0xA6, 0xA1,
        0xB4, 0xB3, 0xBA, 0xBD, 0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
        0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA, 0xB7, 0xB0, 0xB9, 0xBE,
        0xAB, 0xAC, 0xA5, 0xA2, 0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
        0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32, 0x1F, 0x18, 0x11, 0x16,
        0x03, 0x04, 0x0D, 0x0A, 0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
        0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A, 0x89, 0x8E, 0x87, 0x80,
        0x95, 0x92, 0x9B, 0x9C, 0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
        0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC, 0xC1, 0xC6, 0xCF, 0xC8,
        0xDD, 0xDA, 0xD3, 0xD4, 0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
        0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44, 0x19, 0x1E, 0x17, 0x10,
        0x05, 0x02, 0x0B, 0x0C, 0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
        0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B, 0x76, 0x71, 0x78, 0x7F,
        0x6A, 0x6D, 0x64, 0x63, 0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
        0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13, 0xAE, 0xA9, 0xA0, 0xA7,
        0xB2, 0xB5, 0xBC, 0xBB, 0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
        0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB, 0xE6, 0xE1, 0xE8, 0xEF,
        0xFA, 0xFD, 0xF4, 0xF3
    ];
    var crc = 0x00;
    for (var j = 0; j < data.length; j++) {
        crc = table[crc ^ data[j]];
    }
    return crc;
}

/**
 * TTN Uplink-Decoder für EMU Professional II LoRa (3/100 und 3/5 identisch)
 * Dekodiert ALLE bekannten Register-IDs, egal welche per Downlink gewählt wurden.
 * Quelle der IDs: Manual 1490 V3.0, Kap. "Measurement-Registers"
 */

// id: [Länge, Name, Typ, Skalierung]
var REG = {
  0x00: [4, "index",              "u32", 1],
  0x01: [4, "timestamp",          "u32", 1],
  0x02: [4, "timestamp_prev",     "u32", 1],
  0x03: [4, "energy_import_T1_Wh","u32", 1],
  0x04: [4, "energy_import_T2_Wh","u32", 1],
  0x05: [4, "energy_export_T1_Wh","u32", 1],
  0x06: [4, "energy_export_T2_Wh","u32", 1],
  0x07: [4, "reactive_import_T1_varh","u32", 1],
  0x08: [4, "reactive_import_T2_varh","u32", 1],
  0x09: [4, "reactive_export_T1_varh","u32", 1],
  0x0A: [4, "reactive_export_T2_varh","u32", 1],
  0x0B: [4, "power_L123_W",       "i32", 1],
  0x0C: [4, "power_L1_W",         "i32", 1],
  0x0D: [4, "power_L2_W",         "i32", 1],
  0x0E: [4, "power_L3_W",         "i32", 1],
  0x0F: [4, "current_L123_mA",    "i32", 1],
  0x10: [4, "current_L1_mA",      "i32", 1],
  0x11: [4, "current_L2_mA",      "i32", 1],
  0x12: [4, "current_L3_mA",      "i32", 1],
  0x13: [4, "reserved",           "i32", 1],
  0x14: [4, "voltage_L1_V",       "i32", 0.1],
  0x15: [4, "voltage_L2_V",       "i32", 0.1],
  0x16: [4, "voltage_L3_V",       "i32", 0.1],
  0x17: [1, "pf_L1",              "i8",  0.01],
  0x18: [1, "pf_L2",              "i8",  0.01],
  0x19: [1, "pf_L3",              "i8",  0.01],
  0x1A: [2, "frequency_Hz",       "i16", 0.1],
  0x1B: [4, "power_avg_W",        "i32", 1],
  0x1C: [4, "energy_import_T1_kWh","u32", 1],
  0x1D: [4, "energy_import_T2_kWh","u32", 1],
  0x1E: [4, "energy_export_T1_kWh","u32", 1],
  0x1F: [4, "energy_export_T2_kWh","u32", 1],
  0x20: [4, "reactive_import_T1_kvarh","u32", 1],
  0x21: [4, "reactive_import_T2_kvarh","u32", 1],
  0x22: [4, "reactive_export_T1_kvarh","u32", 1],
  0x23: [4, "reactive_export_T2_kvarh","u32", 1],
  0x24: [8, "energy_import_T1_Wh64","u64", 1],
  0x25: [8, "energy_import_T2_Wh64","u64", 1],
  0x26: [8, "energy_export_T1_Wh64","u64", 1],
  0x27: [8, "energy_export_T2_Wh64","u64", 1],
  0x28: [8, "reactive_import_T1_varh64","u64", 1],
  0x29: [8, "reactive_import_T2_varh64","u64", 1],
  0x2A: [8, "reactive_export_T1_varh64","u64", 1],
  0x2B: [8, "reactive_export_T2_varh64","u64", 1],
  0xF0: [1, "error_code",         "u8",  1],
  0xF1: [4, "serial_number",      "hex", 1],
  0xF2: [4, "factory_number",     "hex", 1],
  0xF3: [2, "ct_primary",         "u16", 1],
  0xF4: [2, "ct_secondary",       "u16", 1],
  0xF5: [2, "vt_primary",         "u16", 1],
  0xF6: [2, "vt_secondary",       "u16", 1],
  0xF7: [1, "meter_type",         "u8",  1],
  0xF8: [4, "mid_year",           "bcd", 1],
  0xF9: [4, "manufacture_year",   "bcd", 1],
  0xFA: [4, "firmware",           "ascii", 1],
  0xFB: [4, "mid_version",        "ascii", 1],
  0xFC: [4, "manufacturer",       "ascii", 1],
  0xFD: [4, "hardware_index",     "ascii", 1],
  0xFE: [4, "system_time",        "u32", 1],
  0xFF: [1, "error_code",         "u8",  1]   // Default-Uplink laut Manual nutzt 0xFF
};

function decodeUplink(input) {
  var b = input.bytes;
  var out = { data: {}, warnings: [] };

  if (b.length <= 2) {                      // DeviceTimeReq / Status
    out.data.status_only = true;
    return out;
  }

  var body = b.slice(0, -1);
  if (crc8(body) !== b[b.length - 1]) {
    out.warnings.push("CRC-8 wrong");
  }

  out.data.fport = input.fPort;
  out.data.timestamp = u32(b, 0);           // erste 4 Bytes immer Datalogger-Zeitstempel

  var i = 4;
  while (i < b.length - 1) {
    var id = b[i++];
    var r = REG[id];
    if (!r) { out.warnings.push("unknown id 0x" + id.toString(16) + " at " + (i - 1)); break; }
    var len = r[0], name = r[1], type = r[2], scale = r[3];
    if (i + len > b.length - 1) { out.warnings.push("truncated " + name); break; }

    var v;
    switch (type) {
      case "u8":  v = b[i]; break;
      case "i8":  v = (b[i] << 24) >> 24; break;
      case "u16": v = b[i] | (b[i+1] << 8); break;
      case "i16": v = ((b[i] | (b[i+1] << 8)) << 16) >> 16; break;
      case "u32": v = u32(b, i); break;
      case "i32": v = u32(b, i) | 0; break;
      case "u64": v = u32(b, i) + u32(b, i + 4) * 4294967296; break;
      case "hex": v = u32(b, i).toString(16); break;
      case "bcd": v = u32(b, i).toString(16); break;
      case "ascii": v = String.fromCharCode(b[i], b[i+1], b[i+2], b[i+3]); break;
    }
    if (scale !== 1 && typeof v === "number") v = Math.round(v * scale * 1000) / 1000;
    out.data[name] = v;
    i += len;
  }

  // Komfortwerte
  // Total = T1 + T2 (unabhängig von Tarifumschaltung); nimmt was vorhanden ist
  var d = out.data, wh = null;
  function add(v) { if (v !== undefined) wh = (wh || 0) + v; }
  add(d.energy_import_T1_Wh);   add(d.energy_import_T2_Wh);     // 0x03, 0x04
  add(d.energy_import_T1_Wh64); add(d.energy_import_T2_Wh64);   // 0x24, 0x25
  if (wh !== null) {
    d.energy_kWh_inc = wh / 1000;
  } else if (d.energy_import_T1_kWh !== undefined || d.energy_import_T2_kWh !== undefined) {
    d.energy_kWh_inc = (d.energy_import_T1_kWh || 0) + (d.energy_import_T2_kWh || 0); // 0x1C, 0x1D
  }
  if (out.data.error_code !== undefined) {
    out.data.error_flags = decodeError(out.data.error_code);
  }
  if (out.warnings.length === 0) delete out.warnings;
  return out;
}

function decodeError(e) {
  var names = ["time_set","ct_ratio_adjusted","vt_ratio_adjusted","impulse_length_adjusted",
               "impulse_ratio_adjusted","voltage_interruption","time_not_valid","logbook_full"];
  var f = [];
  for (var k = 0; k < 8; k++) if (e & (1 << k)) f.push(names[k]);
  return f;
}

function u32(d, o) {
  return (d[o+3] << 24 | d[o+2] << 16 | d[o+1] << 8 | d[o]) >>> 0;
}

function crc8(data) {
  var table = [
    0x00,0x07,0x0E,0x09,0x1C,0x1B,0x12,0x15,0x38,0x3F,0x36,0x31,0x24,0x23,0x2A,0x2D,
    0x70,0x77,0x7E,0x79,0x6C,0x6B,0x62,0x65,0x48,0x4F,0x46,0x41,0x54,0x53,0x5A,0x5D,
    0xE0,0xE7,0xEE,0xE9,0xFC,0xFB,0xF2,0xF5,0xD8,0xDF,0xD6,0xD1,0xC4,0xC3,0xCA,0xCD,
    0x90,0x97,0x9E,0x99,0x8C,0x8B,0x82,0x85,0xA8,0xAF,0xA6,0xA1,0xB4,0xB3,0xBA,0xBD,
    0xC7,0xC0,0xC9,0xCE,0xDB,0xDC,0xD5,0xD2,0xFF,0xF8,0xF1,0xF6,0xE3,0xE4,0xED,0xEA,
    0xB7,0xB0,0xB9,0xBE,0xAB,0xAC,0xA5,0xA2,0x8F,0x88,0x81,0x86,0x93,0x94,0x9D,0x9A,
    0x27,0x20,0x29,0x2E,0x3B,0x3C,0x35,0x32,0x1F,0x18,0x11,0x16,0x03,0x04,0x0D,0x0A,
    0x57,0x50,0x59,0x5E,0x4B,0x4C,0x45,0x42,0x6F,0x68,0x61,0x66,0x73,0x74,0x7D,0x7A,
    0x89,0x8E,0x87,0x80,0x95,0x92,0x9B,0x9C,0xB1,0xB6,0xBF,0xB8,0xAD,0xAA,0xA3,0xA4,
    0xF9,0xFE,0xF7,0xF0,0xE5,0xE2,0xEB,0xEC,0xC1,0xC6,0xCF,0xC8,0xDD,0xDA,0xD3,0xD4,
    0x69,0x6E,0x67,0x60,0x75,0x72,0x7B,0x7C,0x51,0x56,0x5F,0x58,0x4D,0x4A,0x43,0x44,
    0x19,0x1E,0x17,0x10,0x05,0x02,0x0B,0x0C,0x21,0x26,0x2F,0x28,0x3D,0x3A,0x33,0x34,
    0x4E,0x49,0x40,0x47,0x52,0x55,0x5C,0x5B,0x76,0x71,0x78,0x7F,0x6A,0x6D,0x64,0x63,
    0x3E,0x39,0x30,0x37,0x22,0x25,0x2C,0x2B,0x06,0x01,0x08,0x0F,0x1A,0x1D,0x14,0x13,
    0xAE,0xA9,0xA0,0xA7,0xB2,0xB5,0xBC,0xBB,0x96,0x91,0x98,0x9F,0x8A,0x8D,0x84,0x83,
    0xDE,0xD9,0xD0,0xD7,0xC2,0xC5,0xCC,0xCB,0xE6,0xE1,0xE8,0xEF,0xFA,0xFD,0xF4,0xF3
  ];
  var crc = 0;
  for (var j = 0; j < data.length; j++) crc = table[crc ^ data[j]];
  return crc;
}