BROWAN - Healthy Home Sensor Iaq

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function Decoder(bytes, port) { const decoded = []; // status message if (port !== 103) return [{ variable: "parse_error", value: "Parser error: Port must be 103" }]; if (bytes.length !== 11) return [{ variable: "parse_error", value: "Parser error: Bytes length doesn't match" }]; // status -- byte 0 decoded.push({ variable: "status_event", value: bytes[0] & 0x01 }); decoded.push({ variable: "status_type", value: ((bytes[0] >> 3) & 0x01) ? "Temperature and Humidity sensor" : "IAQ Sensor" }); decoded.push({ variable: "status_temperature_change", value: (bytes[0] >> 4) & 0x01 }); decoded.push({ variable: "status_humidity_change", value: (bytes[0] >> 5) & 0x01 }); decoded.push({ variable: "status_iaq_change", value: (bytes[0] >> 6) & 0x01 }); // battery -- byte 1 (1 to 14) if ([0, 15].includes(bytes[1] & 0x0F)) return [{ variable: "parse_error", value: "Parser error: Battery must be between 2.6 and 3.9 V" }]; decoded.push({ variable: "battery", value: (25 + (bytes[1] & 0x0F)) / 10, unit: "V" }); // temp (pcb) -- byte 2 decoded.push({ variable: "board_temperature", value: (bytes[2] & 0x7F) - 32, unit: "°C" }); // rh -- byte 3 (max 100) if ((bytes[3] & 0x7F) > 100) return [{ variable: "parse_error", value: "Parser error: Max value for humidity is 100%" }]; decoded.push({ variable: "humidity", value: bytes[3] & 0x7F, unit: "%" }); // co2 -- bytes 4, 5 decoded.push({ variable: "eco2", value: bytes.readUInt16BE(4), unit: "ppm" }); // voc -- bytes 6, 7 decoded.push({ variable: "voc", value: bytes.readUInt16BE(6), unit: "ppm" }); // iaq -- bytes 8, 9 (0 to 500) if (bytes.readUInt16BE(8) > 500) return [{ variable: "parse_error", value: "Parser error: Max value for IAQ is 500" }]; decoded.push({ variable: "iaq", value: bytes.readUInt16BE(8) }); // environment temp -- byte 10 decoded.push({ variable: "environment_temperature", value: (bytes[10] & 0x7F) - 32, unit: "°C" }); return decoded; } // let payload = [{ variable: "payload", value: "790a2a5f2744274427442a" }, { variable: "port", value: "103" }]; // let payload = [{ variable: "payload", value: "79ffffffffffffffffffff" }, { variable: "port", value: "103" }]; const data = payload.find((item) => item.variable === "data" || item.variable === "payload" || item.variable === "payload_raw" ); const port = payload.find((item) => item.variable === "port" || item.variable === "fport" ); if (data) { const bytes = Buffer.from(data.value, "hex"); const serie = new Date().getTime(); payload = payload.concat(Decoder(bytes, Number(port.value))).map((x) => ({ ...x, serie })); } // console.log(payload);