esp-open-rtos/extras/bmp280/bmp280.h

/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2016 sheinz (https://github.com/sheinz)
 *
 * 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_H__
#define __BMP280_H__

#include <stdint.h>
#include <stdbool.h>

/**
 * Uncomment to enable debug output.
 */
// #define BMP280_DEBUG

/**
 * BMP280 or BME280 address is 0x77 if SDO pin is high, and is 0x76 if
 * SDO pin is low.
 */
#define BMP280_I2C_ADDRESS_0  0x76
#define BMP280_I2C_ADDRESS_1  0x77

#define BMP280_CHIP_ID  0x58 /* BMP280 has chip-id 0x58 */
#define BME280_CHIP_ID  0x60 /* BME280 has chip-id 0x60 */

/**
 * Mode of BMP280 module operation.
 * Forced - Measurement is initiated by user.
 * Normal - Continues measurement.
 */
typedef enum {
    BMP280_MODE_SLEEP = 0,
    BMP280_MODE_FORCED = 1,
    BMP280_MODE_NORMAL = 3
} BMP280_Mode;

typedef enum {
    BMP280_FILTER_OFF = 0,
    BMP280_FILTER_2 = 1,
    BMP280_FILTER_4 = 2,
    BMP280_FILTER_8 = 3,
    BMP280_FILTER_16 = 4
} BMP280_Filter;

/**
 * Pressure oversampling settings
 */
typedef enum {
    BMP280_SKIPPED = 0,          /* disable */
    BMP280_ULTRA_LOW_POWER = 1,  /* oversampling x1 */
    BMP280_LOW_POWER = 2,        /* oversampling x2 */
    BMP280_STANDARD = 3,         /* oversampling x4 */
    BMP280_HIGH_RES = 4,         /* oversampling x8 */
    BMP280_ULTRA_HIGH_RES = 5    /* oversampling x16 */
} BMP280_Oversampling;

/**
 * Stand by time between measurements in normal mode
 */
typedef enum {
    BMP280_STANDBY_05 = 0,      /* stand by time 0.5ms */
    BMP280_STANDBY_62 = 1,      /* stand by time 62.5ms */
    BMP280_STANDBY_125 = 2,     /* stand by time 125ms */
    BMP280_STANDBY_250 = 3,     /* stand by time 250ms */
    BMP280_STANDBY_500 = 4,     /* stand by time 500ms */
    BMP280_STANDBY_1000 = 5,    /* stand by time 1s */
    BMP280_STANDBY_2000 = 6,    /* stand by time 2s BMP280, 10ms BME280 */
    BMP280_STANDBY_4000 = 7,    /* stand by time 4s BMP280, 20ms BME280 */
} BMP280_StandbyTime;

/**
 * Configuration parameters for BMP280 module.
 * Use function bmp280_init_default_params to use default configuration.
 */
typedef struct {
    BMP280_Mode mode;
    BMP280_Filter filter;
    BMP280_Oversampling oversampling;  // pressure oversampling
    BMP280_Oversampling oversampling_temperature;  // temperature oversampling
    BMP280_Oversampling oversampling_humidity;
    BMP280_StandbyTime standby;
} bmp280_params_t;


typedef struct {
    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;

    /* Humidity compensation for BME280 */
    uint8_t  dig_H1;
    int16_t  dig_H2;
    uint8_t  dig_H3;
    int16_t  dig_H4;
    int16_t  dig_H5;
    int8_t   dig_H6;

    uint8_t  i2c_addr;  /* I2C address. */
    uint8_t  id;        /* Chip ID */
} bmp280_t;

/**
 * Initialize default parameters.
 * Default configuration:
 *      mode: NORAML
 *      filter: OFF
 *      oversampling: x4
 *      standby time: 250ms
 */
void bmp280_init_default_params(bmp280_params_t *params);

/**
 * Initialize BMP280 module, probes for the device, soft resets the device,
 * reads the calibration constants, and configures the device using the supplied
 * parameters. Returns true on success otherwise false.
 *
 * The I2C address is assumed to have been initialized in the dev, and
 * may be either BMP280_I2C_ADDRESS_0 or BMP280_I2C_ADDRESS_1. If the I2C
 * address is unknown then try initializing each in turn.
 *
 * This may be called again to soft reset the device and initialize it again.
 */
bool bmp280_init(bmp280_t *dev, bmp280_params_t *params);

/**
 * Start measurement in forced mode.
 * The module remains in forced mode after this call.
 * Do not call this method in normal mode.
 */
bool bmp280_force_measurement(bmp280_t *dev);

/**
 * Check if BMP280 is busy with measuring temperature/pressure.
 * Return true if BMP280 is busy.
 */
bool bmp280_is_measuring(bmp280_t *dev);

/**
 * Read compensated temperature and pressure data:
 *
 *  Temperature in degrees Celsius times 100.
 *
 *  Pressure in Pascals in fixed point 24 bit integer 8 bit fraction format.
 *
 *  Humidity is optional and only read for the BME280, in percent relative
 *  humidity as a fixed point 22 bit interger and 10 bit fraction format.
 */
bool bmp280_read_fixed(bmp280_t *dev, int32_t *temperature,
                       uint32_t *pressure, uint32_t *humidity);

/**
 * Read compensated temperature and pressure data:
 *  Temperature in degrees Celsius.
 *  Pressure in Pascals.
 *  Humidity is optional and only read for the BME280, in percent relative
 *  humidity.
 */
bool bmp280_read_float(bmp280_t *dev, float *temperature,
                       float *pressure, float *humidity);

#endif  // __BMP280_H__