问题出现的根本原因是芯片返回的16位数据未被正确的转换成相应的物理量,导致结果不正确。下面是一份C/C++示例代码,可以通过以下方式解决该问题:
//读取数据
void readBME280()
{
Wire1.beginTransmission(BME280_address);
Wire1.write(0xF7);
Wire1.endTransmission(false);
Wire1.requestFrom(BME280_address, 8);
uint8_t rawData[8];
for (uint8_t i = 0; i < 8; i++)
{
rawData[i] = Wire1.read();
}
int32_t Digital_Pressure = (rawData[0] << 12) | (rawData[1] << 4) | (rawData[2] >> 4);
int32_t Digital_Temperature = (rawData[3] << 12) | (rawData[4] << 4) | (rawData[5] >> 4);
int32_t Digital_Humidity = (rawData[6] << 8) | rawData[7];
//转换为实际的温度,压力和湿度值
double Temperature = (double)(int32_t)(Digital_Temperature) / 4096.0;
double Pressure = (double)(int32_t)(Digital_Pressure) / 4096.0;
double Humidity = (double)(int32_t)(Digital_Humidity) / 1024.0;
//输出结果
Serial.print("Temperature: ");
Serial.print(Temperature);
Serial.println(" degrees C ");
Serial.print("Pressure: ");
Serial.print(Pressure);
Serial.println(" Pa ");
Serial.print("Humidity: ");
Serial.print(Humidity);
Serial.println(" %");
}
在代码中,将芯片返回的16位数据通过按位或运算符组合成32位变量,然后将其转换为浮点数表示的实际物理量。这样就可以避免获取到负数的问题了。