miro
Cargo

function Decoder(payload, metadata) {
    // Decode an uplink message from a buffer
    // Payload - array of bytes
    // Metadata - key/value object

    /** Decoder **/

    // Decode payload to JSON
    var data = decodeToJson(payload);

    if (!("end_device_ids" in data && "uplink_message" in data)) {
        return {};
    }

    var deviceName = data.end_device_ids.dev_eui;
    var deviceType = 'miro Nomad';
    var groupName = 'Tracker Demos';

    data = data.uplink_message;

    var payload_hex = base64ToHex(data.frm_payload);
    var bytes = hexToBytes(payload_hex);
    var decoded = Decode(bytes, data.f_port);

    // Result object with device/asset attributes/telemetry data
    var result = {
        // Use deviceName and deviceType or assetName and assetType, but not both.
        deviceName: deviceName,
        deviceType: deviceType,
        groupName: groupName,
        attributes: {
            dr: data.settings.data_rate.lora.spreading_factor,
        },
        telemetry: decoded,
    };

    if (data.f_port == 100) {
        // Welcome message
        // Input example: 01010503000a04393137337e377e0d

        switch (bytes[1]) {
            case 1:
                result.deviceType = 'miro Nomad';
                break;
            case 3:
                result.deviceType = 'miro Cargo';
                break;
            default:
                break;
        }

        result.attributes.firmware = 'v' + bytes[2].toString() + '.' + bytes[3].toString() + '.' + (bytes[4] * 256 + bytes[5]).toString();
    }


    if (data.f_port == 212) {
        // GIT revision
        // Returns base64-encoded HEX string of firmware GIT revision
        // Input example: 41e44999f5678de41701cbcb22fcc55bbb4c5bfb

        result.attributes.git_revision = data.data;
    }

    // Use RSSI and SNR of the first gateway in the gateway list
    var rssiGW0 = data.rx_metadata[0].rssi;
    var snrGW0 = data.rx_metadata[0].snr;
    var freq = parseInt(data.settings.frequency);

    if (Array.isArray(result.telemetry)) {
        var obj = {
            'bat': data.bat,
            'rssi': rssiGW0,
            'freq': freq,
            'snr': snrGW0,
            'hex': payload_hex,
            'port': data.f_port,
        };
        result.telemetry.push(obj);
    } else if ("ts" in result.telemetry) {
        array = [];
        array.push(result.telemetry);
        var obj = {
            'bat': data.bat,
            'rssi': rssiGW0,
            'freq': freq,
            'snr': snrGW0,
            'hex': payload_hex,
            'port': data.f_port,
        };
        array.push(obj);
        result.telemetry = array;
    } else {
        result.telemetry.bat = data.bat;
        result.telemetry.rssi = rssiGW0;
        result.telemetry.freq = freq;
        result.telemetry.snr = snrGW0;
        result.telemetry.hex = payload_hex;
        result.telemetry.port = data.f_port;
    }

    /** Helper functions **/

    function base64ToHex(str) {
        var raw = atob(str);
        var result = '';
        for (var i = 0; i < raw.length; i++) {
            var hex = raw.charCodeAt(i).toString(16);
            result += (hex.length === 2 ? hex : '0' + hex);
        }
        return result;
    }

    function decodeToString(payload) {
        return String.fromCharCode.apply(String, payload);
    }

    function decodeToJson(payload) {
        // Convert payload to string
        var str = decodeToString(payload);

        // Parse string to JSON
        var data = JSON.parse(str);
        return data;
    }

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

        var decoded = {};

        if (port === 100) {
            decoded.reset_source = bytes[6];
        }

        if (port === 101) {
            // Status message
            // Input example: 000000000b290481000334cb0002d57c0000000100000000010a03b2ffc0006003d00fcca624144d001a0002000000
            // Returns status information
            // Note: Not all fields are taken into account here

            var system_time_ms = (bytes[0] << 56 | bytes[1] << 48 | bytes[2] << 40 | bytes[3] << 32 | bytes[4] << 24 | bytes[5] << 16 | bytes[6] << 8 | bytes[7]) >>> 0;
            var temperature = (bytes[24] << 8 | bytes[25]) >>> 0;
            var pressure = (bytes[26] << 8 | bytes[27]) >>> 0;
            var x = (bytes[28] << 8 | bytes[29]) >>> 0;
            var y = (bytes[30] << 8 | bytes[31]) >>> 0;
            var z = (bytes[32] << 8 | bytes[33]) >>> 0;
            var battery_mv = (bytes[34] << 8 | bytes[35]) >>> 0;

            var dat = (bytes[8] << 24 | bytes[9] << 16 | bytes[10] << 8 | bytes[11]) >>> 0;
            var tim = (bytes[12] << 24 | bytes[13] << 16 | bytes[14] << 8 | bytes[15]) >>> 0;

            // Conversion to signed integer (2's complement)
            if (temperature > 0x7FFF) {
                temperature = -(0xFFFF - temperature + 1);
            }
            if (x > 0x7FFF) {
                x = -(0xFFFF - x + 1);
            }
            if (y > 0x7FFF) {
                y = -(0xFFFF - y + 1);
            }
            if (z > 0x7FFF) {
                z = -(0xFFFF - z + 1);
            }

            decoded = [];
            var ts = getTimestamp(dat, tim);
            decoded.push({
                ts: ts,
                values: {
                    battery_lorawan: bytes[36],
                    gps_ttf_s: bytes[37],
                    gps_signal: bytes[42],
                    battery_v: battery_mv / 1000.0,
                    system_time_s: system_time_ms / 1000.0,
                    temperature_deg: temperature / 10.0,
                    pressure_hpa: pressure / 1.0,
                    orientation_x_g: x / 1000.0,
                    orientation_y_g: y / 1000.0,
                    orientation_z_g: z / 1000.0,
                    sta_date_ddmmyy: dat,
                    sta_time_hhmmss: tim,
                    sta_unixtime_ms: ts,
                },
            });
        }

        if (port === 103) {
            // Location message
            // Returns date and time as DDMMYY and HHMMSS
            // Returns latitude, longitude and altitude as float
            // Input example: 0002717900024c6e00396fc4fff44f9500001d7e

            var dat = (bytes[0] << 24 | bytes[1] << 16 | bytes[2] << 8 | bytes[3]) >>> 0;
            var tim = (bytes[4] << 24 | bytes[5] << 16 | bytes[6] << 8 | bytes[7]) >>> 0;
            var lat = (bytes[8] << 24 | bytes[9] << 16 | bytes[10] << 8 | bytes[11]) >>> 0;
            var lon = (bytes[12] << 24 | bytes[13] << 16 | bytes[14] << 8 | bytes[15]) >>> 0;
            var alt = (bytes[16] << 24 | bytes[17] << 16 | bytes[18] << 8 | bytes[19]) >>> 0;

            // Conversion to signed integer (2's complement)
            if (lat > 0x7FFFFFFF) {
                lat = -(0xFFFFFFFF - lat + 1);
            }
            if (lon > 0x7FFFFFFF) {
                lon = -(0xFFFFFFFF - lon + 1);
            }
            if (alt > 0x7FFFFFFF) {
                alt = -(0xFFFFFFFF - alt + 1);
            }

            if ((lat != 0) && (lon != 0)) {
                decoded = [];
                var ts = getTimestamp(dat, tim);
                decoded.push({
                    ts: ts,
                    values: {
                        gps_dat: dat,
                        gps_tim: tim,
                        gps_lat: (lat / 100000.0),
                        gps_lon: (lon / 100000.0),
                        gps_alt: (alt / 100.0),
                        unixtime_ms: ts,
                    },
                });
            }
        }

        if (port === 220) {
            // AT interface
            // Input example: 41545f4552524f52
            // Returns base64-encoded ASCII string of AT command response

            decoded.at_reply = bin2String(bytes);
        }

        return decoded;
    }

    // Convert a hex string to a byte array
    function hexToBytes(hex) {
        for (var bytes = [], c = 0; c < hex.length; c += 2)
            bytes.push(parseInt(hex.substr(c, 2), 16));
        return bytes;
    }

    function getTimestamp(ddmmyy, hhmmss) {
        day = parseInt(ddmmyy / 10000, 10);
        month = parseInt(ddmmyy / 100 - day * 100, 10);
        year = parseInt(ddmmyy - month * 100 - day * 10000 + 2000, 10);
        hour = parseInt(hhmmss / 10000, 10);
        minute = parseInt(hhmmss / 100 - hour * 100, 10);
        second = parseInt(hhmmss - minute * 100 - hour * 10000, 10);

        date = new Date(year, month - 1, day, hour, minute, second)
        return date.valueOf();
    }

    function bin2String(array) {
        var result = "";
        for (var i = 0; i < array.length; i++) {
            result += String.fromCharCode(parseInt(array[i], 2));
        }
        return result;
    }

    return result;
}