C1QX NB-IoT packet format

Packet for Temperature + Humidity + CO2 version

Every packet includes these pieces of information:

• packet type
• devices unique serial number
• battery status indicator
• temperature (in degrees centigrate) reading
• humidity (in % of relative humidity) reading
• CO2 (in parts-per-million) reading

Example parser in Python3

def parse(packet):
    d = {"points": []}

    # < means little endian
    d["packet_type"] = packet[0]

    if d["packet_type"] == 1:
        d["node_id"] = struct.unpack("<I", bytes(packet[1:5]))[0]
        d["points"].append({"note": "battery", "key": 66, "value": packet[5]})
        d["points"].append(
            {
                "note": "temperature_c",
                "key": 67,
                "value": struct.unpack("<f", bytes(packet[6:10]))[0],
            }
        )
        d["points"].append(
            {
                "note": "humidity_rh",
                "key": 74,
                "value": struct.unpack("<f", bytes(packet[10:14]))[0],
            }
        )
        d["points"].append(
            {
                "note": "co2_ppm",
                "key": 122,
                "value": struct.unpack("<f", bytes(packet[14:18]))[0],
            }
        )

    return d