BMP280_DEV.h

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/*
  BMP280_DEV is an I2C/SPI compatible library for the Bosch BMP280 barometer.
 
    Copyright (C) Martin Lindupp 2019
 
    V1.0.0 -- Initial release
    V1.0.1 -- Added ESP32 HSPI support and change library to unique name
    V1.0.2 -- Modification to allow external creation of HSPI object on ESP32
    V1.0.3 -- Changed library name in the library.properties file
    V1.0.5 -- Fixed bug in BMP280_DEV::getTemperature() function, thanks to Jon M.
    V1.0.6 -- Merged multiple instances and initialisation pull requests by sensslen
    V1.0.8 -- Used default arguments for begin() member function and
                        added example using multiple BMP280 devices with SPI comms in NORMAL mode
    V1.0.9 -- Moved writeMask to Device class and improved measurement detection code
    V1.0.10 -- Modification to allow user-defined pins for I2C operation on the ESP8266
    V1.0.12 -- Allow sea level pressure calibration using setSeaLevelPressure() function
    V1.0.14 -- Fix uninitialised structures, thanks to David Jade investigating and
                         flagging up this issue
    V1.0.16 -- Modification to allow user-defined pins for I2C operation on the ESP32
    V1.0.17 -- Added getCurrentTemperature(), getCurrentPressure(), getCurrentTempPres()
                         getCurrentAltitude() and getCurrentMeasurements() functions,
                         to allow the BMP280 to be read directly without checking the measuring bit
    V1.0.18 -- Initialise "device" constructor member variables in the same order they are declared
    V1.0.19 -- Allow for additional TwoWire instances
    V1.0.20 -- Removed default parameter causing ESP32 compilation error with user defined I2C pins
    V1.0.21 -- Fixed uninitialised "Wire" pointer for ESP8266/ESP32 with user defined I2C pins
 
    The MIT License (MIT)
    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:
    The above copyright notice and this permission notice shall be included in all
    copies or substantial portions of the Software.
    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    SOFTWARE.
*/
 
#ifndef BMP280_DEV_h
#define BMP280_DEV_h
 
#include "libs/Device.h"
 
// BMP280_DEV Definitions
 
#define BMP280_I2C_ADDR     0x77 // The BMP280 I2C address
#define BMP280_I2C_ALT_ADDR 0x76 // The BMP280 I2C alternate address
#define DEVICE_ID           0x58 // The BMP280 device ID
#define RESET_CODE          0xB6 // The BMP280 reset code
 
enum SPIPort
{
    BMP280_SPI0,
    BMP280_SPI1
};
 
// BMP280_DEV Registers
 
enum
{
    BMP280_TRIM_PARAMS = 0x88, // Trim parameter registers' base sub-address
    BMP280_DEVICE_ID = 0xD0,   // Device ID register sub-address
    BMP280_RESET = 0xE0,       // Reset register sub-address
    BMP280_STATUS = 0xF3,      // Status register sub-address
    BMP280_CTRL_MEAS = 0xF4,   // Control and measurement register sub-address
    BMP280_CONFIG = 0xF5,      // Configuration register sub-address
    BMP280_PRES_MSB = 0xF7,    // Pressure Most Significant Byte (MSB) register sub-address
    BMP280_PRES_LSB = 0xF8,    // Pressure Least Significant Byte (LSB) register sub-address
    BMP280_PRES_XLSB = 0xF9,   // Pressure eXtended Least Significant Byte (XLSB) register sub-address
    BMP280_TEMP_MSB = 0xFA,    // Pressure Most Significant Byte (MSB) register sub-address
    BMP280_TEMP_LSB = 0xFB,    // Pressure Least Significant Byte (LSB) register sub-address
    BMP280_TEMP_XLSB = 0xFC    // Pressure eXtended Least Significant Byte (XLSB) register sub-address
};
 
// BMP280_DEV Modes
 
enum Mode
{
    SLEEP_MODE = 0x00, // Device mode bitfield in the control and measurement register
    FORCED_MODE = 0x01,
    NORMAL_MODE = 0x03
};
 
// BMP280_DEV Register bit field Definitions
 
enum Oversampling
{
    OVERSAMPLING_SKIP = 0x00, // Oversampling bit fields in the control and measurement register
    OVERSAMPLING_X1 = 0x01,
    OVERSAMPLING_X2 = 0x02,
    OVERSAMPLING_X4 = 0x03,
    OVERSAMPLING_X8 = 0x04,
    OVERSAMPLING_X16 = 0x05
};
 
enum IIRFilter
{
    IIR_FILTER_OFF = 0x00, // Infinite Impulse Response (IIR) filter bit field in the configuration register
    IIR_FILTER_2 = 0x01,
    IIR_FILTER_4 = 0x02,
    IIR_FILTER_8 = 0x03,
    IIR_FILTER_16 = 0x04
};
 
enum TimeStandby
{
    TIME_STANDBY_05MS = 0x00, // Time standby bit field in the configuration register
    TIME_STANDBY_62MS = 0x01,
    TIME_STANDBY_125MS = 0x02,
    TIME_STANDBY_250MS = 0x03,
    TIME_STANDBY_500MS = 0x04,
    TIME_STANDBY_1000MS = 0x05,
    TIME_STANDBY_2000MS = 0x06,
    TIME_STANDBY_4000MS = 0x07
};
 
// BMP280_DEV Class definition
 
class BMP280_DEV : public Device
{ // Derive the BMP280_DEV class from the Device class
  public:
    BMP280_DEV(TwoWire &twoWire = Wire); // BMP280_DEV object for I2C operation
#ifdef ARDUINO_ESP8266_GENERIC
    BMP280_DEV(uint8_t sda, uint8_t scl,
               TwoWire &twoWire = Wire); // BMP280_DEV object for ESP8266 I2C operation with user-defined pins
#endif
    BMP280_DEV(uint8_t cs); // BMP280_DEV object for SPI operation
#ifdef ARDUINO_ESP32_DEV
    BMP280_DEV(uint8_t sda, uint8_t scl,
               TwoWire &twoWire = Wire); // BMP280_DEV object for ESP32 I2C operation with user-defined pins
    BMP280_DEV(uint8_t cs, uint8_t spiPort,
               SPIClass &spiClass); // BMP280_DEV object for SPI1 with supplied SPIClass object
#endif
    uint8_t begin(Mode mode = SLEEP_MODE, // Initialise the barometer with arguments
                  Oversampling presOversampling = OVERSAMPLING_X16, Oversampling tempOversampling = OVERSAMPLING_X2,
                  IIRFilter iirFilter = IIR_FILTER_OFF, TimeStandby timeStandby = TIME_STANDBY_05MS);
    uint8_t begin(Mode mode, uint8_t addr); // Initialise the barometer specifying start mode and I2C addrss
    uint8_t begin(uint8_t addr);  // Initialise the barometer specifying I2C address with default initialisation
    void reset();                 // Soft reset the barometer
    void startNormalConversion(); // Start continuous measurement in NORMAL_MODE
    void startForcedConversion(); // Start a one shot measurement in FORCED_MODE
    void stopConversion();        // Stop the conversion and return to SLEEP_MODE
    void setPresOversampling(Oversampling presOversampling); // Set the pressure oversampling: OFF, X1, X2, X4, X8, X16
    void setTempOversampling(
        Oversampling tempOversampling);     // Set the temperature oversampling: OFF, X1, X2, X4, X8, X16
    void setIIRFilter(IIRFilter iirFilter); // Set the IIR filter setting: OFF, 2, 4, 8, 16
    void setTimeStandby(
        TimeStandby timeStandby); // Set the time standby measurement interval: 0.5, 62, 125, 250, 500ms, 1s, 2s, 4s
    void setSeaLevelPressure(float pressure = 1013.23f); // Set the sea level pressure value
    void getCurrentTemperature(
        float &temperature); // Get the current temperature measurement without checking the measuring bit
    uint8_t getTemperature(float &temperature); // Get a temperature measurement
    void getCurrentPressure(float &pressure);   // Get the current pressure without checking the measuring bit
    uint8_t getPressure(float &pressure);       // Get a pressure measurement
    void getCurrentTempPres(
        float &temperature,
        float &pressure); // Get the current temperature and pressure without checking the measuring bit
    uint8_t getTempPres(float &temperature, float &pressure); // Get a temperature and pressure measurement
    void getCurrentAltitude(float &altitude); // Get the current altitude without checking the measuring bit
    uint8_t getAltitude(float &altitude);     // Get an altitude measurement
    void getCurrentMeasurements(float &temperature, float &pressure,
                                float &altitude); // Get all measurements without checking the measuring bit
    uint8_t getMeasurements(float &temperature, float &pressure,
                            float &altitude); // Get temperature, pressure and altitude measurements
  protected:
  private:
    void setMode(Mode mode); // Set the barometer mode
    void setCtrlMeasRegister(Mode mode, Oversampling presOversampling,
                             Oversampling tempOversamping); // Set the BMP280 control and measurement register
    void setConfigRegister(IIRFilter iirFilter, TimeStandby timeStandby); // Set the BMP280 configuration register
    uint8_t dataReady();                                                  // Checks if a measurement is ready
 
    struct
    { // The BMP280 compensation trim parameters (coefficients)
        uint16_t dig_T1;
        int16_t dig_T2;
        int16_t dig_T3;
        uint16_t dig_P1;
        int16_t dig_P2;
        int16_t dig_P3;
        int16_t dig_P4;
        int16_t dig_P5;
        int16_t dig_P6;
        int16_t dig_P7;
        int16_t dig_P8;
        int16_t dig_P9;
    } params;
 
    union { // Copy of the BMP280's configuration register
        struct
        {
            uint8_t spi3w_en : 1;
            uint8_t : 1;
            uint8_t filter : 3;
            uint8_t t_sb : 3;
        } bit;
        uint8_t reg;
    } config = {.reg = 0};
 
    union { // Copy of the BMP280's control and measurement register
        struct
        {
            uint8_t mode : 2;
            uint8_t osrs_p : 3;
            uint8_t osrs_t : 3;
        } bit;
        uint8_t reg;
    } ctrl_meas = {.reg = 0};
 
    union { // Copy of the BMP280's status register
        struct
        {
            uint8_t im_update : 1;
            uint8_t : 2;
            uint8_t measuring : 1;
        } bit;
        uint8_t reg;
    } status = {.reg = 0};
 
    int32_t t_fine;                                    // Bosch t_fine variable
    int32_t bmp280_compensate_T_int32(int32_t adc_T);  // Bosch temperature compensation function
    uint32_t bmp280_compensate_P_int64(int32_t adc_P); // Bosch pressure compensation function
    bool previous_measuring;                           // Previous measuring state
    float sea_level_pressure = 1013.23f;               // Sea level pressure
};
 
#endif