ErriezBMX280.h

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/*
 * MIT License
 *
 * Copyright (c) 2020 Erriez
 *
 * 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 ERRIEZ_BME280_H_
#define ERRIEZ_BME280_H_

#include <Arduino.h>
#include <Wire.h>

// I2C address
#define BMX280_I2C_ADDR             0x76    
#define BMX280_I2C_ADDR_ALT         0x77    

// Register defines
#define BMX280_REG_DIG_T1           0x88    
#define BMX280_REG_DIG_T2           0x8A    
#define BMX280_REG_DIG_T3           0x8C    

#define BMX280_REG_DIG_P1           0x8E    
#define BMX280_REG_DIG_P2           0x90    
#define BMX280_REG_DIG_P3           0x92    
#define BMX280_REG_DIG_P4           0x94    
#define BMX280_REG_DIG_P5           0x96    
#define BMX280_REG_DIG_P6           0x98    
#define BMX280_REG_DIG_P7           0x9A    
#define BMX280_REG_DIG_P8           0x9C    
#define BMX280_REG_DIG_P9           0x9E    

#define BME280_REG_DIG_H1           0xA1    
#define BME280_REG_DIG_H2           0xE1    
#define BME280_REG_DIG_H3           0xE3    
#define BME280_REG_DIG_H4           0xE4    
#define BME280_REG_DIG_H5           0xE5    
#define BME280_REG_DIG_H6           0xE7    

#define BME280_REG_CHIPID           0xD0    
#define BME280_REG_RESET            0xE0    

#define BME280_REG_CTRL_HUM         0xF2    
#define BMX280_REG_STATUS           0XF3    
#define BMX280_REG_CTRL_MEAS        0xF4    
#define BMX280_REG_CONFIG           0xF5    
#define BMX280_REG_PRESS            0xF7    
#define BMX280_REG_TEMP             0xFA    
#define BME280_REG_HUM              0xFD    

// Bit defines
#define CHIP_ID_BMP280              0x58    
#define CHIP_ID_BME280              0x60    
#define RESET_KEY                   0xB6    
#define STATUS_IM_UPDATE            0       


typedef enum {
    BMX280_MODE_SLEEP = 0b00,               
    BMX280_MODE_FORCED = 0b01,              
    BMX280_MODE_NORMAL = 0b11               
} BMX280_Mode_e;

typedef enum {
    BMX280_SAMPLING_NONE = 0b000,           
    BMX280_SAMPLING_X1 = 0b001,             
    BMX280_SAMPLING_X2 = 0b010,             
    BMX280_SAMPLING_X4 = 0b011,             
    BMX280_SAMPLING_X8 = 0b100,             
    BMX280_SAMPLING_X16 = 0b101             
} BMX280_Sampling_e;

typedef enum {
    BMX280_FILTER_OFF = 0b000,              
    BMX280_FILTER_X2 = 0b001,               
    BMX280_FILTER_X4 = 0b010,               
    BMX280_FILTER_X8 = 0b011,               
    BMX280_FILTER_X16 = 0b100               
} BMX280_Filter_e;

typedef enum {
    BMX280_STANDBY_MS_0_5 = 0b000,          
    BMX280_STANDBY_MS_10 = 0b110,           
    BMX280_STANDBY_MS_20 = 0b111,           
    BMX280_STANDBY_MS_62_5 = 0b001,         
    BMX280_STANDBY_MS_125 = 0b010,          
    BMX280_STANDBY_MS_250 = 0b011,          
    BMX280_STANDBY_MS_500 = 0b100,          
    BMX280_STANDBY_MS_1000 = 0b101          
} BMX280_Standby_e;

class ErriezBMX280
{
public:
    // Constructor
    ErriezBMX280(uint8_t i2cAddr);

    // Initialization
    bool begin();
    uint8_t getChipID();

    // BMP280/BME280
    float readTemperature();
    float readPressure();
    float readAltitude(float seaLevel);

    // BME280 only
    float readHumidity();

    // Configuration
    void setSampling(BMX280_Mode_e mode = BMX280_MODE_NORMAL,
                     BMX280_Sampling_e tempSampling = BMX280_SAMPLING_X16,
                     BMX280_Sampling_e pressSampling = BMX280_SAMPLING_X16,
                     BMX280_Sampling_e humSampling = BMX280_SAMPLING_X16,
                     BMX280_Filter_e filter = BMX280_FILTER_OFF,
                     BMX280_Standby_e standbyDuration = BMX280_STANDBY_MS_0_5);

    // Register access
    uint8_t read8(uint8_t reg);
    uint16_t read16(uint8_t reg);
    uint16_t read16_LE(uint8_t reg); // little endian unsigned
    int16_t readS16_LE(uint8_t reg); // little endian signed
    uint32_t read24(uint8_t reg);
    void write8(uint8_t reg, uint8_t value);

private:
    uint8_t _i2cAddr;   
    uint8_t _chipID;    
    int32_t _t_fine;    

    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;

    uint8_t _dig_H1;
    int16_t _dig_H2;
    uint8_t _dig_H3;
    int16_t _dig_H4;
    int16_t _dig_H5;
    int8_t _dig_H6;

    // Read coefficient registers
    void readCoefficients(void);
};

#endif // ERRIEZ_BMX280_H_