MEMS Ammonia Sensor Module Introduction The M1002 ammonia gas sensor module is an ammonia gas module developed using a MEMS micro gas sensor that can be used to detect the NH3 gas content in the air. The module has a high sensitivity to NH3 gas. The module is aging, commissioned, calibrated, and calibrated for good consistency and long-term stability. Main Feature High sensitivity, high resolution, low power consumption, long life, multiple output modes such as UART, analog voltage signal, PWM waveform, high stability, excellent linear output.

The data length reported by the serial port of the module is fixed at 24 bytes, and the current valid bits are: frame header (0xAA) + temperature (4 bytes) + voltage 1 + voltage 2 + voltage 3 (all voltages are 4 bytes) + gas Type (1 byte) + Concentration (4 bytes) + Alarm/Level (1 byte) + The 24th byte is fixed as cumulative check code Temperature, voltage, concentration and other 4 bytes of data are in hexadecimal When parsed into decimal, the high-order is in the back, the low-order is in the front, and then divided by 1000 to get the decimal floating-point number.

Gas concentration 8F 02 00 00 -->02 8F --> 655 -->0.655 Alarm level 00 Inspection code (cumulative) 72 The analysis procedure of the cumulative check code is as follows: uint8_t Checksum(uint8_t *p,uint8_t len) { uint8_:i; uint32_t sum = 0; for(i = G;i < len;i++) { sum -= p[i]; } sum = sum & (OxFF); return sum; } Serial port command: The module can send commands through the serial port to achieve some functions, as follows: (1) AA 00 FA switches the module to question and answer mode or active upload, the module initializes the default active upload mode, through this command can be in two modes...

Precautions 1. Conditions that must be avoided 1.1 Exposure to volatile silicon compound vapor The module should avoid exposure to silicon adhesives, hair spray, silicone rubber, putty or other places where volatile silicon compounds are present. Otherwise, the sensitivity of the module will be reduced or will not respond. 1.2 Highly corrosive environment Exposure of the module to high concentrations of corrosive gases (such as H2S, SOX, Cl2, HCl, etc.) will cause corrosion or destruction of the sensor heating materials and sensor leads in the module, and will cause sensitivity The irreversible...