高级气象站 v2.0：BME280 实时监测温度/气压/湿度/海拔 (Windows 10 IoT Core)

项目简介

打造紧凑气象站，精准测量温度、气压、湿度与海拔，数据可上云分析。

硬件准备

树莓派 2 接面包板，按 Fritzing 图 (见下方 Schematics) 接线 BME280 (或 BMP280)。若持有 BMP280 请参考 Weather Station v1。

软件框架

基础代码来自 GitHub – ms-iot/adafruitsample。打开 Lesson_203v2\StartSolution\lesson_203v2.sln 编辑 mainpage.xaml.cs。完整版位于 Lesson_203v2\FullSolution\lesson_203v2.sln。

MainPage.xaml.cs 关键代码

引用传感器类并初始化：

public sealed partial class MainPage : Page {
    BME280 BME280;  // 传感器对象
    // ...
    // OnNavigatedTo 中初始化
    BME280 = new BME280Sensor();
    await BME280.Initialize();
}

采集 10 次样本并输出调试控制台：

float temp = 0, pressure = 0, altitude = 0, humidity = 0;
const float seaLevelPressure = 1022.00f;
for (int i = 0; i < 10; i++) {
    temp = await BME280.ReadTemperature();
    pressure = await BME280.ReadPreasure();  // 原拼写保留兼容
    altitude = await BME280.ReadAltitude(seaLevelPressure);
    humidity = await BME280.ReadHumidity();
    Debug.WriteLine("Temperature: " + temp.ToString() + " deg C");
    Debug.WriteLine("Humidity: " + humidity.ToString() + " %");
    Debug.WriteLine("Pressure: " + pressure.ToString() + " Pa");
    Debug.WriteLine("Altitude: " + altitude.ToString() + " m");
    Debug.WriteLine("\n");
}

BME280.cs 核心实现

I2C 连接设置 (Fast Mode, 总线 I2C1)、设备签名校验 (0x58)、校准系数读取、控制寄存器配置 (0x3F/0x03)、补偿算法 (按 BMP280 数据手册) 均已封装。

关键读取函数：

public async Task<float> ReadTemperature() {
    if (!init) await Begin();
    byte tmsb = ReadByte((byte)eRegisters.BMP280_REGISTER_TEMPDATA_MSB);
    byte tlsb = ReadByte((byte)eRegisters.BMP280_REGISTER_TEMPDATA_LSB);
    byte txlsb = ReadByte((byte)eRegisters.BMP280_REGISTER_TEMPDATA_XLSB);
    Int32 t = (tmsb << 12) + (tlsb << 4) + (txlsb >> 4);
    double temp = BMP280_compensate_T_double(t);
    return (float)temp;
}

public async Task<float> ReadPreasure() {
    if (!init) await Begin();
    if (t_fine == Int32.MinValue) await ReadTemperature();
    byte tmsb = ReadByte((byte)eRegisters.BMP280_REGISTER_PRESSUREDATA_MSB);
    byte tlsb = ReadByte((byte)eRegisters.BMP280_REGISTER_PRESSUREDATA_LSB);
    byte txlsb = ReadByte((byte)eRegisters.BMP280_REGISTER_PRESSUREDATA_XLSB);
    Int32 t = (tmsb << 12) + (tlsb << 4) + (txlsb >> 4);
    Int64 pres = BMP280_compensate_P_Int64(t);
    return ((float)pres) / 256;
}

public async Task<float> ReadAltitude(float seaLevel) {
    if (!init) await Begin();
    float pressure = await ReadPreasure();
    pressure /= 100;  // Pa → hPa
    return 44330.0f * (1.0f - (float)Math.Pow((pressure / seaLevel), 0.1903f));
}

预期输出示例

Temperature: 24.46189 deg C
Humidity: 54.372 %
Pressure: 99738.73 Pa
Altitude: 205.1726 m

来源： Weather Station V 2.0