346 lines
13 KiB
C#
346 lines
13 KiB
C#
|
// Licensed to the .NET Foundation under one or more agreements.
|
|||
|
|
// The .NET Foundation licenses this file to you under the MIT license.
|
|||
|
|
// See the LICENSE file in the project root for more information.
|
|||
|
|
|
|||
|
|
using System;
|
|||
|
|
using System.Buffers.Binary;
|
|||
|
|
using System.Device.I2c;
|
|||
|
|
using System.IO;
|
|||
|
|
using NucuCar.Sensors.Environment.Bmxx80.CalibrationData;
|
|||
|
|
using NucuCar.Sensors.Environment.Bmxx80.Register;
|
|||
|
|
using NucuCar.Sensors.Environment.Bmxx80.Units;
|
|||
|
|
|
|||
|
|
namespace NucuCar.Sensors.Environment.Bmxx80
|
|||
|
|
{
|
|||
|
|
/// <summary>
|
|||
|
|
/// Represents the core functionality of the Bmxx80 family.
|
|||
|
|
/// </summary>
|
|||
|
|
public abstract class Bmxx80Base : IDisposable
|
|||
|
|
{
|
|||
|
|
/// <summary>
|
|||
|
|
/// Calibration data for the sensor.
|
|||
|
|
/// </summary>
|
|||
|
|
internal Bmxx80CalibrationData _calibrationData;
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// I2C device used to communicate with the device.
|
|||
|
|
/// </summary>
|
|||
|
|
protected I2cDevice _i2cDevice;
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Chosen communication protocol.
|
|||
|
|
/// </summary>
|
|||
|
|
protected CommunicationProtocol _communicationProtocol;
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// The control register of the sensor.
|
|||
|
|
/// </summary>
|
|||
|
|
protected byte _controlRegister;
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Bmxx80 communication protocol.
|
|||
|
|
/// </summary>
|
|||
|
|
public enum CommunicationProtocol
|
|||
|
|
{
|
|||
|
|
/// <summary>
|
|||
|
|
/// I²C communication protocol.
|
|||
|
|
/// </summary>
|
|||
|
|
I2c
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// The variable TemperatureFine carries a fine resolution temperature value over to the
|
|||
|
|
/// pressure compensation formula and could be implemented as a global variable.
|
|||
|
|
/// </summary>
|
|||
|
|
protected int TemperatureFine
|
|||
|
|
{
|
|||
|
|
get;
|
|||
|
|
set;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// The temperature calibration factor.
|
|||
|
|
/// </summary>
|
|||
|
|
protected virtual int TempCalibrationFactor => 1;
|
|||
|
|
|
|||
|
|
private Sampling _temperatureSampling;
|
|||
|
|
private Sampling _pressureSampling;
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Initializes a new instance of the <see cref="Bmxx80Base"/> class.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="deviceId">The ID of the device.</param>
|
|||
|
|
/// <param name="i2cDevice">The <see cref="I2cDevice"/> to create with.</param>
|
|||
|
|
/// <exception cref="ArgumentNullException">Thrown when the given <see cref="I2cDevice"/> is null.</exception>
|
|||
|
|
/// <exception cref="IOException">Thrown when the device cannot be found on the bus.</exception>
|
|||
|
|
protected Bmxx80Base(byte deviceId, I2cDevice i2cDevice)
|
|||
|
|
{
|
|||
|
|
_i2cDevice = i2cDevice ?? throw new ArgumentNullException(nameof(i2cDevice));
|
|||
|
|
_i2cDevice.WriteByte((byte)Bmxx80Register.CHIPID);
|
|||
|
|
|
|||
|
|
byte readSignature = _i2cDevice.ReadByte();
|
|||
|
|
|
|||
|
|
if (readSignature != deviceId)
|
|||
|
|
{
|
|||
|
|
throw new IOException($"Unable to find a chip with id {deviceId}");
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
ReadCalibrationData();
|
|||
|
|
SetDefaultConfiguration();
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Gets or sets the pressure sampling.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <exception cref="ArgumentOutOfRangeException">Thrown when the <see cref="Sampling"/> is set to an undefined mode.</exception>
|
|||
|
|
public Sampling PressureSampling
|
|||
|
|
{
|
|||
|
|
get => _pressureSampling;
|
|||
|
|
set
|
|||
|
|
{
|
|||
|
|
byte status = Read8BitsFromRegister(_controlRegister);
|
|||
|
|
status = (byte)(status & 0b1110_0011);
|
|||
|
|
status = (byte)(status | (byte)value << 2);
|
|||
|
|
|
|||
|
|
Span<byte> command = stackalloc[]
|
|||
|
|
{
|
|||
|
|
_controlRegister, status
|
|||
|
|
};
|
|||
|
|
_i2cDevice.Write(command);
|
|||
|
|
_pressureSampling = value;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Gets or sets the temperature sampling.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <exception cref="ArgumentOutOfRangeException">Thrown when the <see cref="Sampling"/> is set to an undefined mode.</exception>
|
|||
|
|
public Sampling TemperatureSampling
|
|||
|
|
{
|
|||
|
|
get => _temperatureSampling;
|
|||
|
|
set
|
|||
|
|
{
|
|||
|
|
byte status = Read8BitsFromRegister(_controlRegister);
|
|||
|
|
status = (byte)(status & 0b0001_1111);
|
|||
|
|
status = (byte)(status | (byte)value << 5);
|
|||
|
|
|
|||
|
|
Span<byte> command = stackalloc[]
|
|||
|
|
{
|
|||
|
|
_controlRegister, status
|
|||
|
|
};
|
|||
|
|
_i2cDevice.Write(command);
|
|||
|
|
_temperatureSampling = value;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// When called, the device is reset using the complete power-on-reset procedure.
|
|||
|
|
/// The device will reset to the default configuration.
|
|||
|
|
/// </summary>
|
|||
|
|
public void Reset()
|
|||
|
|
{
|
|||
|
|
const byte resetCommand = 0xB6;
|
|||
|
|
Span<byte> command = stackalloc[]
|
|||
|
|
{
|
|||
|
|
(byte)Bmxx80Register.RESET, resetCommand
|
|||
|
|
};
|
|||
|
|
_i2cDevice.Write(command);
|
|||
|
|
|
|||
|
|
SetDefaultConfiguration();
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Reads the temperature. A return value indicates whether the reading succeeded.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="temperature">
|
|||
|
|
/// Contains the measured temperature if the <see cref="TemperatureSampling"/> was not set to <see cref="Sampling.Skipped"/>.
|
|||
|
|
/// Contains <see cref="double.NaN"/> otherwise.
|
|||
|
|
/// </param>
|
|||
|
|
/// <returns><code>true</code> if measurement was not skipped, otherwise <code>false</code>.</returns>
|
|||
|
|
public abstract bool TryReadTemperature(out Temperature temperature);
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Reads the pressure. A return value indicates whether the reading succeeded.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="pressure">
|
|||
|
|
/// Contains the measured pressure if the <see cref="PressureSampling"/> was not set to <see cref="Sampling.Skipped"/>.
|
|||
|
|
/// Contains <see cref="double.NaN"/> otherwise.
|
|||
|
|
/// </param>
|
|||
|
|
/// <returns><code>true</code> if measurement was not skipped, otherwise <code>false</code>.</returns>
|
|||
|
|
public abstract bool TryReadPressure(out Pressure pressure);
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Compensates the temperature.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="adcTemperature">The temperature value read from the device.</param>
|
|||
|
|
/// <returns>The <see cref="Temperature"/>.</returns>
|
|||
|
|
protected Temperature CompensateTemperature(int adcTemperature)
|
|||
|
|
{
|
|||
|
|
// The temperature is calculated using the compensation formula in the BMP280 datasheet.
|
|||
|
|
// See: https://cdn-shop.adafruit.com/datasheets/BST-BMP280-DS001-11.pdf
|
|||
|
|
double var1 = ((adcTemperature / 16384.0) - (_calibrationData.DigT1 / 1024.0)) * _calibrationData.DigT2;
|
|||
|
|
double var2 = (adcTemperature / 131072.0) - (_calibrationData.DigT1 / 8192.0);
|
|||
|
|
var2 *= var2 * _calibrationData.DigT3 * TempCalibrationFactor;
|
|||
|
|
|
|||
|
|
TemperatureFine = (int)(var1 + var2);
|
|||
|
|
|
|||
|
|
double temp = (var1 + var2) / 5120.0;
|
|||
|
|
return Temperature.FromCelsius(temp);
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Reads an 8 bit value from a register.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="register">Register to read from.</param>
|
|||
|
|
/// <returns>Value from register.</returns>
|
|||
|
|
protected internal byte Read8BitsFromRegister(byte register)
|
|||
|
|
{
|
|||
|
|
if (_communicationProtocol == CommunicationProtocol.I2c)
|
|||
|
|
{
|
|||
|
|
_i2cDevice.WriteByte(register);
|
|||
|
|
byte value = _i2cDevice.ReadByte();
|
|||
|
|
return value;
|
|||
|
|
}
|
|||
|
|
else
|
|||
|
|
{
|
|||
|
|
throw new NotImplementedException();
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Reads a 16 bit value over I2C.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="register">Register to read from.</param>
|
|||
|
|
/// <param name="endianness">Interpretation of the bytes (big or little endian).</param>
|
|||
|
|
/// <returns>Value from register.</returns>
|
|||
|
|
protected internal ushort Read16BitsFromRegister(byte register, Endianness endianness = Endianness.LittleEndian)
|
|||
|
|
{
|
|||
|
|
Span<byte> bytes = stackalloc byte[2];
|
|||
|
|
switch (_communicationProtocol)
|
|||
|
|
{
|
|||
|
|
case CommunicationProtocol.I2c:
|
|||
|
|
_i2cDevice.WriteByte(register);
|
|||
|
|
_i2cDevice.Read(bytes);
|
|||
|
|
break;
|
|||
|
|
default:
|
|||
|
|
throw new NotImplementedException();
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
return endianness switch
|
|||
|
|
{
|
|||
|
|
Endianness.LittleEndian => BinaryPrimitives.ReadUInt16LittleEndian(bytes),
|
|||
|
|
Endianness.BigEndian => BinaryPrimitives.ReadUInt16BigEndian(bytes),
|
|||
|
|
_ => throw new ArgumentOutOfRangeException(nameof(endianness), endianness, null)
|
|||
|
|
};
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Reads a 24 bit value over I2C.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="register">Register to read from.</param>
|
|||
|
|
/// <param name="endianness">Interpretation of the bytes (big or little endian).</param>
|
|||
|
|
/// <returns>Value from register.</returns>
|
|||
|
|
protected internal uint Read24BitsFromRegister(byte register, Endianness endianness = Endianness.LittleEndian)
|
|||
|
|
{
|
|||
|
|
Span<byte> bytes = stackalloc byte[4];
|
|||
|
|
switch (_communicationProtocol)
|
|||
|
|
{
|
|||
|
|
case CommunicationProtocol.I2c:
|
|||
|
|
_i2cDevice.WriteByte(register);
|
|||
|
|
_i2cDevice.Read(bytes.Slice(1));
|
|||
|
|
break;
|
|||
|
|
default:
|
|||
|
|
throw new NotImplementedException();
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
return endianness switch
|
|||
|
|
{
|
|||
|
|
Endianness.LittleEndian => BinaryPrimitives.ReadUInt32LittleEndian(bytes),
|
|||
|
|
Endianness.BigEndian => BinaryPrimitives.ReadUInt32BigEndian(bytes),
|
|||
|
|
_ => throw new ArgumentOutOfRangeException(nameof(endianness), endianness, null)
|
|||
|
|
};
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Converts byte to <see cref="Sampling"/>.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="value">Value to convert.</param>
|
|||
|
|
/// <returns><see cref="Sampling"/></returns>
|
|||
|
|
protected Sampling ByteToSampling(byte value)
|
|||
|
|
{
|
|||
|
|
// Values >=5 equals UltraHighResolution.
|
|||
|
|
if (value >= 5)
|
|||
|
|
{
|
|||
|
|
return Sampling.UltraHighResolution;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
return (Sampling)value;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Sets the default configuration for the sensor.
|
|||
|
|
/// </summary>
|
|||
|
|
protected virtual void SetDefaultConfiguration()
|
|||
|
|
{
|
|||
|
|
PressureSampling = Sampling.UltraLowPower;
|
|||
|
|
TemperatureSampling = Sampling.UltraLowPower;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Specifies the Endianness of a device.
|
|||
|
|
/// </summary>
|
|||
|
|
protected internal enum Endianness
|
|||
|
|
{
|
|||
|
|
/// <summary>
|
|||
|
|
/// Indicates little endian.
|
|||
|
|
/// </summary>
|
|||
|
|
LittleEndian,
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Indicates big endian.
|
|||
|
|
/// </summary>
|
|||
|
|
BigEndian
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
private void ReadCalibrationData()
|
|||
|
|
{
|
|||
|
|
switch (this)
|
|||
|
|
{
|
|||
|
|
case NucuCar.Sensors.Environment.Bmxx80.Bme280 _:
|
|||
|
|
_calibrationData = new Bme280CalibrationData();
|
|||
|
|
_controlRegister = (byte)Bmx280Register.CTRL_MEAS;
|
|||
|
|
break;
|
|||
|
|
case NucuCar.Sensors.Environment.Bmxx80.Bmp280 _:
|
|||
|
|
_calibrationData = new Bmp280CalibrationData();
|
|||
|
|
_controlRegister = (byte)Bmx280Register.CTRL_MEAS;
|
|||
|
|
break;
|
|||
|
|
case NucuCar.Sensors.Environment.Bmxx80.Bme680 _:
|
|||
|
|
_calibrationData = new Bme680CalibrationData();
|
|||
|
|
_controlRegister = (byte)Bme680Register.CTRL_MEAS;
|
|||
|
|
break;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
_calibrationData.ReadFromDevice(this);
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Cleanup.
|
|||
|
|
/// </summary>
|
|||
|
|
public void Dispose()
|
|||
|
|
{
|
|||
|
|
Dispose(true);
|
|||
|
|
GC.SuppressFinalize(this);
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// Releases the unmanaged resources used by the Bmxx80 and optionally releases the managed resources.
|
|||
|
|
/// </summary>
|
|||
|
|
/// <param name="disposing">True to release both managed and unmanaged resources; false to release only unmanaged resources.</param>
|
|||
|
|
protected virtual void Dispose(bool disposing)
|
|||
|
|
{
|
|||
|
|
_i2cDevice?.Dispose();
|
|||
|
|
_i2cDevice = null;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|