TTN Smart Sensor (Gwf)

Codec Preview

function decodeUplink(input) { var bytes = input.bytes; // Decode an uplink message from a buffer // (array) of bytes to an object of fields. var decoded = {}; // gwf protocol byte 0 switch (bytes[0]) { case 0x01: decoded.protocol = "standard"; break; case 0x02: decoded.protocol = "noDueDate"; break; default: decoded.protocol = "unkown"; break; } // manufacturer byte 1,2 decoded.manufacturer = getManufacturer(bytes[1], bytes[2]); // meter id byte 3,4,5,6 decoded.meterId = 0; for (var i = 3; i >= 0; i--) { decoded.meterId = decoded.meterId * 100 + decode(bytes[i + 3]); } //medium byte 7 switch (bytes[7]) { case 0x03: decoded.medium = "Gas"; break; case 0x06: decoded.medium = "Hot Water"; break; case 0x07: decoded.medium = "Water"; break; default: decoded.medium = "Unkown"; } decoded.badEncoder = (((bytes[8] & (1 << 4)) >> 4) & ((bytes[8] & (1 << 6)) >> 6)) !== 0; decoded.noEncoder = (((bytes[8] & (1 << 4)) >> 4) & ((bytes[8] & (1 << 5)) >> 5)) !== 0; decoded.lowBattery = (bytes[8] & (1 << 2)) >> 2 == 1; //actuality duration bytes 10,11 decoded.actualityduration = bytes[10] * 265 + bytes[9]; // register value, bytes 12,13,14,15 var registerValue = 0; var j = 15; while (1) { registerValue += bytes[j]; if (j == 12) break; registerValue *= 256; j--; } decoded.registerValue = registerValue; //byte 16 decoded.reservedBit0 = (bytes[16] & 0x1) == 1; decoded.continousFlow = (bytes[16] & 0x2) == 1; decoded.reservedBit2 = (bytes[16] & 0x4) == 1; decoded.brokenPipe = (bytes[16] & 0x8) == 1; decoded.reservedBit4 = (bytes[16] & 0x10) == 1; //decoded.lowBattery=(bytes[16]&0x20)==1; decoded.backFlow = (bytes[16] & 0x40) == 1; decoded.reservedBit7 = (bytes[16] & 0x80) == 1; //byte 17 decoded.batteryLifeSemesters = (bytes[17] & 0xf8) >> 3; decoded.linkError = (bytes[17] & 0x04) !== 0; //byte 18-19 decoded.crc = "0x" + (bytes[18] * 256 + bytes[19]).toString(16); return { data: decoded, warnings: [], errors: [] }; } function decode(b) { return (b >> 4) * 10 + (b & 0xf); } function getManufacturer(lowByte, highByte) { var valHB = parseInt(highByte); var valLB = parseInt(lowByte); var res = valHB * 256 + valLB; firstLetterCC = res / 32 / 32 + 64; firstLetter = String.fromCharCode(firstLetterCC); secondLetterCC = ((res / 32) % 32) + 64; secondLetter = String.fromCharCode(secondLetterCC); thirdLetterCC = (res % 32) + 64; thirdLetter = String.fromCharCode(thirdLetterCC); return firstLetter.concat(secondLetter, thirdLetter); }