//Method to initialize the BME280 sensor
public async Task Initialize()
{
Debug.WriteLine("BME280::Initialize");
try
{
//Instantiate the I2CConnectionSettings using the device address of the BME280
I2cConnectionSettings settings = new I2cConnectionSettings(BME280_Address);
//Set the I2C bus speed of connection to fast mode
settings.BusSpeed = I2cBusSpeed.FastMode;
//Use the I2CBus device selector to create an advanced query syntax string
string aqs = I2cDevice.GetDeviceSelector(I2CControllerName);
//Use the Windows.Devices.Enumeration.DeviceInformation class to create a collection using the advanced query syntax string
DeviceInformationCollection dis = await DeviceInformation.FindAllAsync(aqs);
//Instantiate the the BME280 I2C device using the device id of the I2CBus and the I2CConnectionSettings
bme280 = await I2cDevice.FromIdAsync(dis[0].Id, settings);
//Check if device was found
if (bme280 == null)
{
Debug.WriteLine("Device not found");
}
}
catch (Exception e)
{
Debug.WriteLine("Exception: " + e.Message + "\n" + e.StackTrace);
throw;
}
byte[] readChipID = new byte[] { (byte)eRegisters.BME280_REGISTER_CHIPID };
byte[] ReadBuffer = new byte[] { 0xFF };
//Read the device signature
bme280.WriteRead(readChipID, ReadBuffer);
Debug.WriteLine("BME280 Signature: " + ReadBuffer[0].ToString());
//Verify the device signature
if (ReadBuffer[0] != BME280_Signature)
{
Debug.WriteLine("BME280::Begin Signature Mismatch.");
return;
}
//Read the coefficients table
CalibrationData = ReadCoefficeints();
//Set configuration registers
WriteConfigRegister();
WriteControlMeasurementRegister();
WriteControlRegisterHumidity();
//Set configuration registers again to ensure configuration of humidity
WriteConfigRegister();
WriteControlMeasurementRegister();
WriteControlRegisterHumidity();
//Dummy read temp to setup t_fine
ReadTemperature();
}
//Method to read the caliberation data from the registers
private BME280_CalibrationData ReadCoefficeints()
{
// 16 bit calibration data is stored as Little Endian, the helper method will do the byte swap.
CalibrationData = new BME280_CalibrationData();
// Read temperature calibration data
CalibrationData.dig_T1 = ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_T1);
CalibrationData.dig_T2 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_T2);
CalibrationData.dig_T3 = (short)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 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P2);
CalibrationData.dig_P3 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P3);
CalibrationData.dig_P4 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P4);
CalibrationData.dig_P5 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P5);
CalibrationData.dig_P6 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P6);
CalibrationData.dig_P7 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P7);
CalibrationData.dig_P8 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P8);
CalibrationData.dig_P9 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P9);
// Read humidity calibration data
CalibrationData.dig_H1 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H1);
CalibrationData.dig_H2 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_H2);
CalibrationData.dig_H3 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H3);
short e4 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H4_L); // Read 0xE4
short e5 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H4_H); // Read 0xE5
CalibrationData.dig_H4 = (short)((e4 << 4) + (e5 & 0x0F));
short e6 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H5_H); // Read 0xE6
CalibrationData.dig_H5 = (short)((e5 >> 4) + (e6 << 4));
CalibrationData.dig_H6 = (sbyte)ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H6);
return(CalibrationData);
}
//Method to read the caliberation data from the registers
private BME280_CalibrationData ReadCoefficeints()
{
// 16 bit calibration data is stored as Little Endian, the helper method will do the byte swap.
CalibrationData = new BME280_CalibrationData();
// Read temperature calibration data
CalibrationData.dig_T1 = ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_T1);
CalibrationData.dig_T2 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_T2);
CalibrationData.dig_T3 = (short)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 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P2);
CalibrationData.dig_P3 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P3);
CalibrationData.dig_P4 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P4);
CalibrationData.dig_P5 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P5);
CalibrationData.dig_P6 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P6);
CalibrationData.dig_P7 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P7);
CalibrationData.dig_P8 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P8);
CalibrationData.dig_P9 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_P9);
// Read humidity calibration data
CalibrationData.dig_H1 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H1);
CalibrationData.dig_H2 = (short)ReadUInt16_LittleEndian((byte)eRegisters.BME280_REGISTER_DIG_H2);
CalibrationData.dig_H3 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H3);
short e4 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H4_L); // Read 0xE4
short e5 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H4_H); // Read 0xE5
CalibrationData.dig_H4 = (short)((e4 << 4) + (e5 & 0x0F));
short e6 = ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H5_H); // Read 0xE6
CalibrationData.dig_H5 = (short)((e5 >> 4) + (e6 << 4));
CalibrationData.dig_H6 = (sbyte)ReadByte((byte)eRegisters.BME280_REGISTER_DIG_H6);
return CalibrationData;
}
//Method to initialize the BME280 sensor
public async Task Initialize()
{
Debug.WriteLine("BME280::Initialize");
try
{
//Instantiate the I2CConnectionSettings using the device address of the BME280
I2cConnectionSettings settings = new I2cConnectionSettings(BME280_Address);
//Set the I2C bus speed of connection to fast mode
settings.BusSpeed = I2cBusSpeed.FastMode;
//Use the I2CBus device selector to create an advanced query syntax string
string aqs = I2cDevice.GetDeviceSelector(I2CControllerName);
//Use the Windows.Devices.Enumeration.DeviceInformation class to create a collection using the advanced query syntax string
DeviceInformationCollection dis = await DeviceInformation.FindAllAsync(aqs);
//Instantiate the the BME280 I2C device using the device id of the I2CBus and the I2CConnectionSettings
bme280 = await I2cDevice.FromIdAsync(dis[0].Id, settings);
//Check if device was found
if (bme280 == null)
{
Debug.WriteLine("Device not found");
}
}
catch (Exception e)
{
Debug.WriteLine("Exception: " + e.Message + "\n" + e.StackTrace);
throw;
}
byte[] readChipID = new byte[] { (byte)eRegisters.BME280_REGISTER_CHIPID };
byte[] ReadBuffer = new byte[] { 0xFF };
//Read the device signature
bme280.WriteRead(readChipID, ReadBuffer);
Debug.WriteLine("BME280 Signature: " + ReadBuffer[0].ToString());
//Verify the device signature
if (ReadBuffer[0] != BME280_Signature)
{
Debug.WriteLine("BME280::Begin Signature Mismatch.");
return;
}
//Read the coefficients table
CalibrationData = ReadCoefficeints();
//Set configuration registers
WriteConfigRegister();
WriteControlMeasurementRegister();
WriteControlRegisterHumidity();
//Set configuration registers again to ensure configuration of humidity
WriteConfigRegister();
WriteControlMeasurementRegister();
WriteControlRegisterHumidity();
//Dummy read temp to setup t_fine
ReadTemperature();
}
