//Method to read the caliberation data from the registers private BME280CalibrationData ReadCoefficeints() { // 16 bit calibration data is stored as Little Endian, the helper method will do the byte swap. CalibrationData = new BME280CalibrationData(); // Read temperature calibration data CalibrationData.dig_T1 = ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_T1); CalibrationData.dig_T2 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_T2); CalibrationData.dig_T3 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_T3); // Read presure calibration data CalibrationData.dig_P1 = ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P1); CalibrationData.dig_P2 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P2); CalibrationData.dig_P3 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P3); CalibrationData.dig_P4 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P4); CalibrationData.dig_P5 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P5); CalibrationData.dig_P6 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P6); CalibrationData.dig_P7 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P7); CalibrationData.dig_P8 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P8); CalibrationData.dig_P9 = (Int16)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P9); CalibrationData.dig_H1 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H1_REG); CalibrationData.dig_H2 = (Int16)((ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H2_MSB) << 8) | ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H2_LSB)); CalibrationData.dig_H3 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H3_REG); CalibrationData.dig_H4 = (Int16)((ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H4_MSB) << 4) | (ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H4_LSB) & 0xF)); CalibrationData.dig_H5 = (Int16)((ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H5_MSB) << 4) | (ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H5_LSB) >> 4)); CalibrationData.dig_H6 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H6_REG); Thread.Sleep(1); return(CalibrationData); }
private void Begin() { Debug.WriteLine("BME280::Begin"); byte[] writeBuffer = new byte[] { (byte)eRegisters.BME280_REGISTER_CHIPID }; byte[] readBuffer = new byte[] { 0xFF }; //Read the device signature WriteRead(writeBuffer, readBuffer); Debug.WriteLine("BME280 Signature: " + readBuffer[0].ToString()); //Verify the device signature if (readBuffer[0] != BME280_Signature) { Debug.WriteLine("BME280::Begin Signature Mismatch."); return; } //Set the initalize variable to true init = true; //Read the coefficients table CalibrationData = ReadCoefficeints(); //Write control register WriteControlRegister(); //Write humidity control register WriteControlRegisterHumidity(); }