bme680.h

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#include "simpletools.h"                      // Include simple tools




#ifndef BME680_H
#define BME680_H

#if defined(__cplusplus)
extern "C" {
#endif

#ifndef  CELSIUS 
  #define  CELSIUS                          (0)
#endif

#ifndef  FAHRENHEIT 
  #define  FAHRENHEIT                       (1)
#endif

#ifndef  KELVIN 
  #define  KELVIN                           (2)
#endif

#ifndef  PASCALS 
  #define  PASCALS                          (0)
#endif

#ifndef  MMHG 
  #define  MMHG                             (1)
#endif

#ifndef  INHG 
  #define  INHG                             (2)
#endif

#ifndef  PSI 
  #define  PSI                              (3)
#endif

#ifndef  METERS 
  #define  METERS                           (0)
#endif

#ifndef  FEET 
  #define  FEET                             (1)
#endif


#ifndef BME680_OS_NONE
  #define BME680_OS_NONE                    (0)
#endif

#ifndef BME680_OS_1X
  #define BME680_OS_1X                      (1)
#endif

#ifndef BME680_OS_2X
  #define BME680_OS_2X                      (2)
#endif

#ifndef BME680_OS_4X
  #define BME680_OS_4X                      (3)
#endif

#ifndef BME680_OS_8X
  #define BME680_OS_8X                      (4)
#endif

#ifndef BME680_OS_16X
  #define BME680_OS_16X                     (5)
#endif


*/
#ifndef BME680_FILTER_SIZE_0
  #define BME680_FILTER_SIZE_0              (0)
#endif

#ifndef BME680_FILTER_SIZE_1
  #define BME680_FILTER_SIZE_1              (1)
#endif

#ifndef BME680_FILTER_SIZE_3
  #define BME680_FILTER_SIZE_3              (2)
#endif

#ifndef BME680_FILTER_SIZE_7
  #define BME680_FILTER_SIZE_7              (3)
#endif

#ifndef BME680_FILTER_SIZE_15
  #define BME680_FILTER_SIZE_15             (4)
#endif

#ifndef BME680_FILTER_SIZE_31
  #define BME680_FILTER_SIZE_31             (5)
#endif

#ifndef BME680_FILTER_SIZE_63
  #define BME680_FILTER_SIZE_63             (6)
#endif

#ifndef BME680_FILTER_SIZE_127
  #define BME680_FILTER_SIZE_127            (7)
#endif


#ifndef BME680_SETTING_AMB_TEMP
  #define BME680_SETTING_AMB_TEMP           (0)
#endif

#ifndef BME680_SETTING_HEATER_TEMP
  #define BME680_SETTING_HEATER_TEMP        (1)
#endif

#ifndef BME680_SETTING_HEATER_DURATION
  #define BME680_SETTING_HEATER_DURATION    (2)
#endif

#ifndef BME680_SETTING_FILTER_SIZE
  #define BME680_SETTING_FILTER_SIZE        (3)
#endif

#ifndef BME680_SETTING_TEMP_SAMPLES
  #define BME680_SETTING_TEMP_SAMPLES       (4)
#endif

#ifndef BME680_SETTING_PRESSURE_SAMPLES
  #define BME680_SETTING_PRESSURE_SAMPLES   (5)
#endif

#ifndef BME680_SETTING_HUMIDITY_SAMPLES
  #define BME680_SETTING_HUMIDITY_SAMPLES   (6)
#endif


typedef struct bme680_st {
  // Setup
  unsigned char dev_id;             // Device ID
  char intf;                        // SPI/i2c interface
  i2c *i2c_ptr;                     // i2c bus
  char sdi_pin;                     // SPI pins
  char sdo_pin;
  char clk_pin;
  char amb_temp;                    // Ambient temperature in (C)
  unsigned short heater_temp;       // Heater temperature (C)
  unsigned char heater_duration;    // Heater duration (ms)
  unsigned char filter_size;
  unsigned char temp_oversample;
  unsigned char pres_oversample;
  unsigned char hum_oversample;
  short sensor_reading_period;
  
  // Calibration Data
  unsigned short par_h1;            // Variables to store calibrated humidity data
  unsigned short par_h2;
  char par_h3;
  char par_h4;
  char par_h5;
  unsigned char par_h6;
  char par_h7;
  char par_gh1;                     // Variables to store calibrated gas data
  short par_gh2; 
  char par_gh3;
  unsigned short par_t1;            // Variables to store calibrated temperature data
  short par_t2;
  char par_t3;                      // Variables to store calibrated pressure data
  unsigned short par_p1;
  short par_p2;
  char par_p3;
  short par_p4;
  short par_p5;
  char par_p6;
  char par_p7;
  short par_p8;
  short par_p9;
  unsigned char par_p10;
  float t_fine;                     // Variable to store t_fine size
  unsigned char res_heat_range;     // Variable to store heater resistance range
  char res_heat_val;                // Variable to store heater resistance value
  char range_sw_err;                // Variable to store error range

  // Readings
  unsigned char status;             // Contains new_data, gasm_valid & heat_stab
  unsigned char gas_index;          // The index of the heater profile used
  unsigned char meas_index;         // Measurement index to track order
  float temperature;                // Temperature in degree celsius
  float pressure;                   // Pressure in Pascal
  float altitude;
  float humidity;                   // Humidity in % relative humidity x1000
  float gas_resistance;             // Gas resistance in Ohms
} bme680_t;


typedef bme680_t bme680;

bme680_t *bme680_openI2C(i2c *i2c_bus, char i2c_addr);

bme680_t *bme680_openSPI(char pin_sdo, char pin_clk, char pin_sdi, char pin_cs);

void bme680_begin(bme680_t *dev);

char bme680_loadSettings(bme680_t *dev);

char bme680_readSensor(bme680_t *dev);

void bme680_write(bme680_t *dev, unsigned char reg_addr, unsigned char *reg_data, unsigned short len);

void bme680_read(bme680_t *dev, unsigned char reg_addr, unsigned char *reg_data, unsigned short len);

void bme680_configure(bme680_t *dev, char setting, int value);

void bme680_close(bme680_t *dev);

float bme680_temperature(bme680_t *dev, char unit);   

float bme680_pressure(bme680_t *dev, char unit);

float bme680_altitude(bme680_t *dev, char unit);

float bme680_humidity(bme680_t *dev);

float bme680_gasResistance(bme680_t *dev);

void bme680_heaterEnable(bme680_t *dev);

void bme680_heaterDisable(bme680_t *dev);

#if defined(__cplusplus)
}
#endif
/* __cplusplus */ 
#endif
/* BME680_H */