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catena-message-generic-decoder-ttn.js
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// This function decodes the records (port 1, format 0x11, 0x14, 0x15, 0x16, 0x17)
// sent by the MCCI Catena 4410/4450/4551 soil/water and power applications.
// For use with console.thethingsnetwork.org
// 2017-09-19 add dewpoints.
// 2017-12-13 fix commments, fix negative soil/water temp, add test vectors.
// 2017-12-15 add format 0x11.
// 2018-04-24 add format 0x16.
// 2018-04-01 add format 0x17.
// 2018-06-13 add air quality.
// 2019-02-13 add simple sensor format (port 2).
// 2019-06-28 add port 3 (no barometric pressure)
// calculate dewpoint (degrees C) given temperature (C) and relative humidity (0..100)
// from http://andrew.rsmas.miami.edu/bmcnoldy/Humidity.html
// rearranged for efficiency and to deal sanely with very low (< 1%) RH
function dewpoint(t, rh) {
var c1 = 243.04;
var c2 = 17.625;
var h = rh / 100;
if (h <= 0.01)
h = 0.01;
else if (h > 1.0)
h = 1.0;
var lnh = Math.log(h);
var tpc1 = t + c1;
var txc2 = t * c2;
var txc2_tpc1 = txc2 / tpc1;
var tdew = c1 * (lnh + txc2_tpc1) / (c2 - lnh - txc2_tpc1);
return tdew;
}
//Calculate Water Level.
function waterlevel(wp) {
var ρ = 1000;
var g = 9.81;
var h = (wp * 1000) / (ρ * g);
return h;
}
function Decoder(bytes, port) {
// Decode an uplink message from a buffer
// (array) of bytes to an object of fields.
var decoded = {};
if (port === 1) {
cmd = bytes[0];
if (cmd == 0x14) {
// decode Catena 4450 M101 data
// test vectors:
// 14 01 18 00 ==> vBat = 1.5
// 14 01 F8 00 ==> vBat = -0.5
// 14 05 F8 00 42 ==> boot: 66, vBat: -0.5
// 14 0D F8 00 42 17 80 59 35 80 ==> adds one temp of 23.5, rh = 50, p = 913.48
// i is used as the index into the message. Start with the flag byte.
var i = 1;
// fetch the bitmap.
var flags = bytes[i++];
if (flags & 0x1) {
// set vRaw to a uint16, and increment pointer
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
// interpret uint16 as an int16 instead.
if (vRaw & 0x8000)
vRaw += -0x10000;
// scale and save in decoded.
decoded.vBat = vRaw / 4096.0;
}
if (flags & 0x2) {
var vRawBus = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (vRawBus & 0x8000)
vRawBus += -0x10000;
decoded.vBus = vRawBus / 4096.0;
}
if (flags & 0x4) {
var iBoot = bytes[i];
i += 1;
decoded.boot = iBoot;
}
if (flags & 0x8) {
// we have temp, pressure, RH
var tRaw = (bytes[i] << 8) + bytes[i + 1];
if (tRaw & 0x8000)
tRaw = -0x10000 + tRaw;
i += 2;
var pRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var hRaw = bytes[i++];
decoded.tempC = tRaw / 256;
decoded.error = "none";
decoded.p = pRaw * 4 / 100.0;
decoded.rh = hRaw / 256 * 100;
decoded.tDewC = dewpoint(decoded.tempC, decoded.rh);
}
if (flags & 0x10) {
// we have lux
var luxRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.lux = luxRaw;
}
if (flags & 0x20) {
// watthour
var powerIn = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var powerOut = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.powerUsedCount = powerIn;
decoded.powerSourcedCount = powerOut;
}
if (flags & 0x40) {
// normalize floating pulses per hour
var floatIn = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var floatOut = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var exp1 = floatIn >> 12;
var exp2 = floatOut >> 12;
var mant1 = (floatIn & 0xFFF) / 4096.0;
var mant2 = (floatOut & 0xFFF) / 4096.0;
var powerPerHourIn = mant1 * Math.pow(2, exp1 - 15) * 60 * 60 * 4;
var powerPerHourOut = mant2 * Math.pow(2, exp2 - 15) * 60 * 60 * 4;
decoded.powerUsedPerHour = powerPerHourIn;
decoded.powerSourcedPerHour = powerPerHourOut;
}
} else if (cmd == 0x15) {
// decode Catena 4450 M102 data
// test vectors:
// 15 01 18 00 ==> vBat = 1.5
// 15 01 F8 00 ==> vBat = -0.5
// 15 05 F8 00 42 ==> boot: 66, vBat: -0.5
// 15 0D F8 00 42 17 80 59 35 80 ==> adds one temp of 23.5, rh = 50, p = 913.48, tDewC = 12.5
// 15 7D 44 60 0D 15 9D 5F CD C3 00 00 1C 11 14 46 E4 ==>
// {
// "boot": 13,
// "error": "none",
// "lux": 0,
// "p": 981,
// "rh": 76.171875,
// "rhSoil": 89.0625,
// "tDewC": 17.236466758309017,
// "tSoil": 20.2734375,
// "tSoilDew": 18.411840342527178,
// "tWater": 28.06640625,
// "tempC": 21.61328125,
// "vBat": 4.2734375,
// }
// 15 7D 43 72 07 17 A4 5F CB A7 01 DB 1C 01 16 AF C3
// {
// "boot": 7,
// "error": "none",
// "lux": 475,
// "p": 980.92,
// "rh": 65.234375,
// "rhSoil": 76.171875,
// "tDewC": 16.732001483771757,
// "tSoil": 22.68359375,
// "tSoilDew": 18.271601276518467,
// "tWater": 28.00390625,
// "tempC": 23.640625,
// "vBat": 4.21533203125
// }
// 15 7D 42 D4 21 F5 9B 5E 5F C1 00 00 01 C1 F9 1B EC
// {
// "boot": 33,
// "error": "none",
// "lux": 0,
// "p": 966.36,
// "rh": 75.390625,
// "rhSoil": 92.1875,
// "tDewC": -13.909882718758952,
// "tSoil": -6.89453125,
// "tSoilDew": -7.948780789914008,
// "tWater": 1.75390625,
// "tempC": -10.39453125,
// "vBat": 4.1767578125
// }
// i is used as the index into the message. Start with the flag byte.
var i = 1;
// fetch the bitmap.
var flags = bytes[i++];
if (flags & 0x1) {
// set vRaw to a uint16, and increment pointer
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
// interpret uint16 as an int16 instead.
if (vRaw & 0x8000)
vRaw += -0x10000;
// scale and save in decoded.
decoded.vBat = vRaw / 4096.0;
}
if (flags & 0x2) {
var vRawBus = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (vRawBus & 0x8000)
vRawBus += -0x10000;
decoded.vBus = vRawBus / 4096.0;
}
if (flags & 0x4) {
var iBoot = bytes[i];
i += 1;
decoded.boot = iBoot;
}
if (flags & 0x8) {
// we have temp, pressure, RH
var tRaw = (bytes[i] << 8) + bytes[i + 1];
if (tRaw & 0x8000)
tRaw = -0x10000 + tRaw;
i += 2;
var pRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var hRaw = bytes[i++];
decoded.tempC = tRaw / 256;
decoded.error = "none";
decoded.p = pRaw * 4 / 100.0;
decoded.rh = hRaw / 256 * 100;
decoded.tDewC = dewpoint(decoded.tempC, decoded.rh);
}
if (flags & 0x10) {
// we have lux
var luxRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.lux = luxRaw;
}
if (flags & 0x20) {
// onewire temperature
var tempRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (tempRaw & 0x8000)
tempRaw = -0x10000 + tempRaw;
decoded.tWater = tempRaw / 256;
}
if (flags & 0x40) {
// temperature followed by RH
var tempRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (tempRaw & 0x8000)
tempRaw = -0x10000 + tempRaw;
var tempRH = bytes[i];
i += 1;
decoded.tSoil = tempRaw / 256;
decoded.rhSoil = tempRH / 256 * 100;
decoded.tSoilDew = dewpoint(decoded.tSoil, decoded.rhSoil);
}
} else if (cmd == 0x11) {
// decode Catena 4410 sensor data
// test vectors:
// 11 01 18 00 ==> vBat = 1.5
// 11 01 F8 00 ==> vBat = -0.5
// 11 05 F8 00 17 80 59 35 80 ==> adds one temp of 23.5, rh = 50, p = 913.48, tDewC = 12.5
// 11 3D 44 60 15 9D 5F CD C3 00 00 1C 11 14 46 E4 ==>
// {
// "error": "none",
// "lux": 0,
// "p": 981,
// "rh": 76.171875,
// "rhSoil": 89.0625,
// "tDewC": 17.236466758309017,
// "tSoil": 20.2734375,
// "tSoilDew": 18.411840342527178,
// "tWater": 28.06640625,
// "tempC": 21.61328125,
// "vBat": 4.2734375,
// }
// 11 3D 43 72 17 A4 5F CB A7 01 DB 1C 01 16 AF C3
// {
// "error": "none",
// "lux": 475,
// "p": 980.92,
// "rh": 65.234375,
// "rhSoil": 76.171875,
// "tDewC": 16.732001483771757,
// "tSoil": 22.68359375,
// "tSoilDew": 18.271601276518467,
// "tWater": 28.00390625,
// "tempC": 23.640625,
// "vBat": 4.21533203125
// }
// i is used as the index into the message. Start with the flag byte.
var i = 1;
// fetch the bitmap.
var flags = bytes[i++];
if (flags & 0x1) {
// set vRaw to a uint16, and increment pointer
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
// interpret uint16 as an int16 instead.
if (vRaw & 0x8000)
vRaw += -0x10000;
// scale and save in decoded.
decoded.vBat = vRaw / 4096.0;
}
if (flags & 0x2) {
var vRawBus = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (vRawBus & 0x8000)
vRawBus += -0x10000;
decoded.vBus = vRawBus / 4096.0;
}
if (flags & 0x4) {
// we have temp, pressure, RH
var tRaw = (bytes[i] << 8) + bytes[i + 1];
if (tRaw & 0x8000)
tRaw = -0x10000 + tRaw;
i += 2;
var pRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var hRaw = bytes[i++];
decoded.tempC = tRaw / 256;
decoded.error = "none";
decoded.p = pRaw * 4 / 100.0;
decoded.rh = hRaw / 256 * 100;
decoded.tDewC = dewpoint(decoded.tempC, decoded.rh);
}
if (flags & 0x8) {
// we have lux
var luxRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.lux = luxRaw;
}
if (flags & 0x10) {
// onewire temperature
var tempRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.tWater = tempRaw / 256;
}
if (flags & 0x20) {
// temperature followed by RH
var tempRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var tempRH = bytes[i];
i += 1;
decoded.tSoil = tempRaw / 256;
decoded.rhSoil = tempRH / 256 * 100;
decoded.tSoilDew = dewpoint(decoded.tSoil, decoded.rhSoil);
}
} else if (cmd == 0x16) {
// decode Catena 4450 Water Level data
// test vectors:
// 17 01 18 00 ==> vBat = 1.5
// 17 01 F8 00 ==> vBat = -0.5
// 17 05 F8 00 42 ==> boot: 66, vBat: -0.5
// 17 0D F8 00 42 17 80 59 35 80 ==> adds one temp of 23.5, rh = 50, p = 913.48
// 16 3D 46 F4 59 1E CB 62 9F 68 00 F7 67 85 ==>
// {
// "water pressure": 01.805
// "boot": 89,
// "error": "none",
// "lux": 247,
// "p": 1009.88,
// "rh": 40.625,
// "tempC": 30.792,
// "vBat": 4.434,
// }
// i is used as the index into the message. Start with the flag byte.
var i = 1;
// fetch the bitmap.
var flags = bytes[i++];
if (flags & 0x1) {
// set vRaw to a uint16, and increment pointer
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
// interpret uint16 as an int16 instead.
if (vRaw & 0x8000)
vRaw += -0x10000;
// scale and save.
decoded.vBat = vRaw / 4096.0;
}
if (flags & 0x2) {
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (vRaw & 0x8000)
vRaw += -0x10000;
decoded.vBus = vRaw / 4096.0;
}
if (flags & 0x4) {
var iBoot = bytes[i];
i += 1;
decoded.boot = iBoot;
}
if (flags & 0x8) {
// we have temp, pressure, RH
var tRaw = (bytes[i] << 8) + bytes[i + 1];
if (tRaw & 0x8000)
tRaw = -0x10000 + tRaw;
i += 2;
var pRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var hRaw = bytes[i++];
decoded.t = tRaw / 256;
decoded.p = pRaw * 4 / 100.0;
decoded.rh = hRaw / 256 * 100;
}
if (flags & 0x10) {
// we have lux
var luxRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.lux = luxRaw;
}
if (flags & 0x20) {
//Decode Rayco Sensor Data.
var wpRaw;
wpRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
//Convert pressure from hPa to kPa. And display payload.
decoded.wPressure = (wpRaw * 4 / 100.0) / 10;
decoded.wLevel = waterlevel(decoded.wPressure);
}
} else if (cmd == 0x17) {
// decode Catena 4460 AQI data
// test vectors:
// 17 01 18 00 ==> vBat = 1.5
// 17 01 F8 00 ==> vBat = -0.5
// 17 05 F8 00 42 ==> boot: 66, vBat: -0.5
// 17 0D F8 00 42 17 80 59 35 80 ==> adds one temp of 23.5, rh = 50, p = 913.48, tDewC = 12.5
// 17 3D 44 60 0D 15 9D 5F CD C3 00 00 F9 07 ==>
// {
// "aqi": 288.875
// "boot": 13,
// "error": "none",
// "lux": 0,
// "p": 981,
// "rh": 76.171875,
// "tDewC": 17.236466758309017,
// "tempC": 21.61328125,
// "vBat": 4.2734375,
// }
// 17 3D 43 72 07 17 A4 5F CB A7 01 DB E9 AF ==>
// {
// "aqi": 154.9375,
// "boot": 7,
// "error": "none",
// "lux": 475,
// "p": 980.92,
// "rh": 65.234375,
// "tDewC": 16.732001483771757,
// "tempC": 23.640625,
// "vBat": 4.21533203125
// }
// 17 FD 3C 05 53 16 EE 61 F1 94 00 A7 DB 91 EB F7 03 ==>
// {
// "boot": 83,
// "error": "none",
// "iaq": 92.53125,
// "iaqQuality": 3,
// "log_r_gas": 5.982421875,
// "lux": 167,
// "p": 1002.92,
// "r_gas": 960333.0490535165,
// "rh": 57.8125,
// "tDewC": 14.178238315794754,
// "tempC": 22.9296875,
// "vBat": 3.751220703125
// }
// i is used as the index into the message. Start with the flag byte.
var i = 1;
// fetch the bitmap.
var flags = bytes[i++];
if (flags & 0x1) {
// set vRaw to a uint16, and increment pointer
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
// interpret uint16 as an int16 instead.
if (vRaw & 0x8000)
vRaw += -0x10000;
// scale and save in decoded.
decoded.vBat = vRaw / 4096.0;
}
if (flags & 0x2) {
var vRawBus = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (vRawBus & 0x8000)
vRawBus += -0x10000;
decoded.vBus = vRawBus / 4096.0;
}
if (flags & 0x4) {
var iBoot = bytes[i];
i += 1;
decoded.boot = iBoot;
}
if (flags & 0x8) {
// we have temp, pressure, RH
var tRaw = (bytes[i] << 8) + bytes[i + 1];
if (tRaw & 0x8000)
tRaw = -0x10000 + tRaw;
i += 2;
var pRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var hRaw = bytes[i++];
decoded.tempC = tRaw / 256;
decoded.error = "none";
decoded.p = pRaw * 4 / 100.0;
decoded.rh = hRaw / 256 * 100;
decoded.tDewC = dewpoint(decoded.tempC, decoded.rh);
}
if (flags & 0x10) {
// we have lux
var luxRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.lux = luxRaw;
}
if (flags & 0x20) {
var rawUflt16 = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var exp1 = rawUflt16 >> 12;
var mant1 = (rawUflt16 & 0xFFF) / 4096.0;
var f_unscaled = mant1 * Math.pow(2, exp1 - 15);
var aqi = f_unscaled * 512;
decoded.iaq = aqi;
}
if (flags & 0x40) {
var rawUflt16 = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var exp1 = rawUflt16 >> 12;
var mant1 = (rawUflt16 & 0xFFF) / 4096.0;
var f_unscaled = mant1 * Math.pow(2, exp1 - 15);
var logGasR = f_unscaled * 16;
var gasR = Math.pow(10, logGasR);
decoded.log_r_gas = logGasR;
decoded.r_gas = gasR;
}
if (flags & 0x80) { // get the miscellaneous flags
var rawFlags = bytes[i];
i += 1;
var iaqQuality = rawFlags & 3;
decoded.iaqQuality = iaqQuality;
}
} else {
// cmd value not recognized.
}
} else if (port === 2) {
// see catena-message-port2-format.md
// i is used as the index into the message. Start with the flag byte.
// note that there's no discriminator.
var i = 0;
// fetch the bitmap.
var flags = bytes[i++];
if (flags & 0x1) {
// set vRaw to a uint16, and increment pointer
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
// interpret uint16 as an int16 instead.
if (vRaw & 0x8000)
vRaw += -0x10000;
// scale and save in decoded.
decoded.vBat = vRaw / 4096.0;
}
if (flags & 0x2) {
var VDDRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (VDDRaw & 0x8000)
VDDRaw += -0x10000;
decoded.VDD = VDDRaw / 4096.0;
}
if (flags & 0x4) {
var iBoot = bytes[i];
i += 1;
decoded.boot = iBoot;
}
if (flags & 0x8) {
// we have temp, pressure, RH
var tRaw = (bytes[i] << 8) + bytes[i + 1];
if (tRaw & 0x8000)
tRaw = -0x10000 + tRaw;
i += 2;
var pRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
var hRaw = bytes[i++];
decoded.tempC = tRaw / 256;
decoded.error = "none";
decoded.p = pRaw * 4 / 100.0;
decoded.rh = hRaw / 256 * 100;
decoded.tDewC = dewpoint(decoded.tempC, decoded.rh);
}
if (flags & 0x10) {
// we have IR, White, UV -- units are C * W/m2,
// where C is a calibration constant.
var irradiance = { };
decoded.irradiance = irradiance;
var lightRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
irradiance.IR = lightRaw;
lightRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
irradiance.White = lightRaw;
lightRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
irradiance.UV = lightRaw;
}
if (flags & 0x20) {
var vRawBus = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (vRawBus & 0x8000)
vRawBus += -0x10000;
decoded.vBus = vRawBus / 4096.0;
}
} else if (port === 3) {
// see catena-message-port3-format.md
// i is used as the index into the message. Start with the flag byte.
// note that there's no discriminator.
var i = 0;
// fetch the bitmap.
var flags = bytes[i++];
if (flags & 0x1) {
// set vRaw to a uint16, and increment pointer
var vRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
// interpret uint16 as an int16 instead.
if (vRaw & 0x8000)
vRaw += -0x10000;
// scale and save in decoded.
decoded.vBat = vRaw / 4096.0;
}
if (flags & 0x2) {
var VDDRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (VDDRaw & 0x8000)
VDDRaw += -0x10000;
decoded.VDD = VDDRaw / 4096.0;
}
if (flags & 0x4) {
var iBoot = bytes[i];
i += 1;
decoded.boot = iBoot;
}
if (flags & 0x8) {
// we have temp, RH (as u2)
var tRaw = (bytes[i] << 8) + bytes[i + 1];
if (tRaw & 0x8000)
tRaw = -0x10000 + tRaw;
i += 2;
var rhRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
decoded.tempC = tRaw / 256;
decoded.error = "none";
decoded.rh = rhRaw / 65535 * 100;
decoded.tDewC = dewpoint(decoded.tempC, decoded.rh);
}
if (flags & 0x10) {
// we have IR, White, UV -- units are C * W/m2,
// where C is a calibration constant.
var irradiance = { };
decoded.irradiance = irradiance;
var lightRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
irradiance.IR = lightRaw;
lightRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
irradiance.White = lightRaw;
lightRaw = (bytes[i] << 8) + bytes[i + 1];
i += 2;
irradiance.UV = lightRaw;
}
if (flags & 0x20) {
var vRawBus = (bytes[i] << 8) + bytes[i + 1];
i += 2;
if (vRawBus & 0x8000)
vRawBus += -0x10000;
decoded.vBus = vRawBus / 4096.0;
}
}
// at this point, decoded has the real values.
return decoded;
}