bme680/bme680.h
2024-08-19 14:17:39 +01:00

228 lines
5.0 KiB
C

#ifndef BME680_H
#define BME680_H
#include <stdint.h>
/* REGISTERS */
/* confuses me too ! */
/* SPI page number 0 => 0x00 to 0x7F */
/* SPI page number 1 => 0x80 to 0xFF */
#define REG_SPI_PAGE(v) ((v > 0x7F) ? 0 : 1)
#define REG_SPI_PAGE_MAP(v) (v == 0 ? "LOW" : "HIGH")
#define REG_STATUS 0x73
#define REG_RESET 0xE0
#define REG_ID 0xD0
#define REG_CONFIG 0x75
#define REG_CTRL_MEAS 0x74
#define REG_CTRL_HUM 0x72
#define REG_CTRL_GAS_1 0x71
#define REG_CTRL_GAS_0 0x70
#define REG_GAS_WAIT_9 0x6D
#define REG_GAS_WAIT_8 0x6C
#define REG_GAS_WAIT_7 0x6B
#define REG_GAS_WAIT_6 0x6A
#define REG_GAS_WAIT_5 0x69
#define REG_GAS_WAIT_4 0x68
#define REG_GAS_WAIT_3 0x67
#define REG_GAS_WAIT_2 0x66
#define REG_GAS_WAIT_1 0x65
#define REG_GAS_WAIT_0 0x64
#define REG_RES_HEAT_9 0x63
#define REG_RES_HEAT_8 0x62
#define REG_RES_HEAT_7 0x61
#define REG_RES_HEAT_6 0x60
#define REG_RES_HEAT_5 0x5F
#define REG_RES_HEAT_4 0x5E
#define REG_RES_HEAT_3 0x5D
#define REG_RES_HEAT_2 0x5C
#define REG_RES_HEAT_1 0x5B
#define REG_RES_HEAT_0 0x5A
#define REG_IDAC_HEAT_9 0x59
#define REG_IDAC_HEAT_8 0x58
#define REG_IDAC_HEAT_7 0x57
#define REG_IDAC_HEAT_6 0x56
#define REG_IDAC_HEAT_5 0x55
#define REG_IDAC_HEAT_4 0x54
#define REG_IDAC_HEAT_3 0x53
#define REG_IDAC_HEAT_2 0x52
#define REG_IDAC_HEAT_1 0x51
#define REG_IDAC_HEAT_0 0x50
#define REG_GAS_R_LSB 0x2B
#define REG_GAS_R_MSB 0x2A
#define REG_HUM_LSB 0x26
#define REG_HUM_MSB 0x25
#define REG_TEMP_XLSB 0x24
#define REG_TEMP_LSB 0x23
#define REG_TEMP_MSB 0x22
#define REG_PRESS_XLSB 0x21
#define REG_PRESS_LSB 0x20
#define REG_PRESS_MSB 0x1F
#define REG_MEAS_STATUS 0x1D
/* END OF REGISTERS */
#define BME680_IS_SPI(m) ((m & 1) == 1)
#define BME680_IS_FLOAT(m) (((m >> 1) & 1) == 0)
#define BME680_GAS_ENABLED(m) (((m >> 2) & 1) == 1)
#define BME680_IDAC(c) (c << 1)
#define BME680_GAS_WAIT(val, scal) ((uint8_t)(((scal & 3) << 6) | (val & 63)))
/* connection modes */
#define BME680_SPI 1
#define BME680_I2C 0
/* calculation modes; int or float calc */
#define BME680_MODE_INT 2
#define BME680_MODE_FLOAT 0
/* to enable gas conversion OR this into mode byte */
#define BME680_ENABLE_GAS 4
/* config values */
#define BME680_OVERSAMPLE_X1 1
#define BME680_OVERSAMPLE_X2 2
#define BME680_OVERSAMPLE_X4 3
#define BME680_OVERSAMPLE_X8 4
#define BME680_OVERSAMPLE_X16 5
/* IIR filter */
#define BME680_IIR_COEFF_0 0
#define BME680_IIR_COEFF_1 1
#define BME680_IIR_COEFF_3 2
#define BME680_IIR_COEFF_7 3
#define BME680_IIR_COEFF_15 4
#define BME680_IIR_COEFF_31 5
#define BME680_IIR_COEFF_63 6
#define BME680_IIR_COEFF_127 7
/* gas related values */
#define BME680_GAS_WAIT_X1 0
#define BME680_GAS_WAIT_X4 1
#define BME680_GAS_WAIT_X16 2
#define BME680_GAS_WAIT_X64 3
/* user supplied spi/i2c functions */
struct bme680_dev {
int (*init) (void);
int (*read) (uint8_t reg, uint8_t *dst, uint32_t size);
int (*write) (uint8_t reg, uint8_t value);
int (*sleep) (uint32_t dur_us);
int (*deinit) (void);
};
struct bme680_cal {
/* temp calibration */
uint16_t par_t1;
int16_t par_t2;
int8_t par_t3;
/* press calibration */
uint16_t par_p1;
int16_t par_p2;
int8_t par_p3;
int16_t par_p4;
int16_t par_p5;
int8_t par_p6;
int8_t par_p7;
int16_t par_p8;
int16_t par_p9;
uint8_t par_p10;
/* humidity calibration */
uint16_t par_h1;
uint16_t par_h2;
int8_t par_h3;
int8_t par_h4;
int8_t par_h5;
uint8_t par_h6;
int8_t par_h7;
/* heater + gas */
uint16_t par_g1;
uint16_t par_g2;
uint16_t par_g3;
uint16_t range_switching_error;
uint8_t res_heat_range;
int8_t res_heat_val;
};
struct bme680_config {
uint8_t osrs_t;
uint8_t osrs_p;
uint8_t osrs_h;
uint8_t filter;
uint8_t idac_heat[10];
uint8_t res_heat[10];
uint8_t gas_wait[10];
uint8_t meas; /* required because you can't read back ctrl regs */
};
struct bme680_comp_float {
double tfine;
double temp;
double press;
double hum;
double gas_res;
};
struct bme680_comp_int {
int32_t tfine;
int32_t temp;
int32_t press;
int32_t hum;
int32_t gas_res;
};
struct bme680_adc {
uint32_t temp;
uint32_t press;
uint32_t hum;
uint32_t gas;
uint32_t gas_range;
};
struct bme680 {
struct bme680_comp_float fcomp;
struct bme680_comp_int icomp;
struct bme680_cal cal;
struct bme680_dev dev;
struct bme680_config cfg;
struct bme680_adc adc;
uint8_t mode;
uint8_t setpoint;
uint8_t spi_page;
uint8_t gas_valid;
uint8_t heat_stab;
};
typedef struct bme680 bme680_t;
int bme680_init(bme680_t *bme680, uint8_t mode);
int bme680_deinit(bme680_t *bme680);
int bme680_reset(bme680_t *bme680);
int bme680_calibrate(bme680_t *bme680);
int bme680_configure(bme680_t *bme680);
int bme680_start(bme680_t *bme680);
int bme680_poll(bme680_t *bme680);
int bme680_read(bme680_t *bme680);
int bme680_write_setpoint_index(bme680_t *bme680);
int bme680_read_setpoint_index(bme680_t *bme680, uint8_t *index);
uint8_t bme680_calc_target(bme680_t *bme680, double target, double ambient);
#endif