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bme280.c
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bme280.c
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/**
*******************************************
* @file bme280.c
* @author Łukasz Juraszek / JuraszekL
* @date 20.04.2023
* @brief Source code for BME280 Driver
* @note https://github.com/JuraszekL/BME280_Driver
*******************************************
*/
/**
* @addtogroup BME280_Driver
* @{
*/
//***************************************
#include <stdint.h>
#include <stddef.h>
#include "bme280.h"
/**
* @defgroup BME280_priv Private Resources
* @brief only for internal library purposes
* @{
*/
/**
* @defgroup BME280_privmacros Macros
* @{
*/
/// concatenate two bytes into signed half-word
#define CAT_I16T(msb, lsb) ((int16_t)(((int16_t)msb << 8) | (int16_t)lsb))
/// concatenate two bytes into unsigned half-word
#define CAT_UI16T(msb, lsb) ((uint16_t)(((uint16_t)msb << 8) | (uint16_t)lsb))
/// check if x is null
#define IS_NULL(x) ((NULL == x))
///@}
/**
* @defgroup BME280_privenums Enums
* @{
*/
/// type of read, used as parameter to call #bme280_read_compensate function
enum { read_all = 0, read_temp, read_press, read_hum};
/// possible value of "mode" variable inside #BME280_t structure
enum { sleep_mode = 0x00, forced_mode = 0x01, normal_mode = 0x03 };
/// possible value of "initialized" variabie inside #BME280_t structure
enum { not_initialized = 0x00, initialized };
///@}
/**
* @struct adc_regs
* @brief keeps raw adc values from sensor, used in #bme280_read_compensate function
* @{
*/
struct adc_regs {
uint8_t press_raw[BME280_PRESS_ADC_LEN]; ///< keeps raw adc value of pressure
uint8_t temp_raw[BME280_TEMP_ADC_LEN]; ///< keeps raw adc value of temperature
uint8_t hum_raw[BME280_HUM_ADC_LEN]; ///< keeps raw adc value of humidity
} __attribute__((aligned(1))) ;
///@}
/**
*@defgroup BME280_privfunct Functions
*@{
*/
/**
* @brief read compensation data
*
* Function reads individual compensation data from sensor and stores them into #BME280_calibration_data
* inside *Dev structure
*/
static int8_t bme280_read_compensation_parameters(BME280_t *Dev);
/**
* @brief read and compensate measured values
*
* Function reads selected adc values from sensor, converts them into single variables and
* compensate with calibration data stored in #BME280_calibration_data inside *Dev structure. These
* variales are then returned as single integer values.
*/
static int8_t bme280_read_compensate(uint8_t read_type, BME280_t *Dev, BME280_S32_t *temp,
BME280_U32_t *press, BME280_U32_t *hum);
/**
* @brief convert buffer to single variable
*
* Function converts raw adc values of temperature or pressure to single #BME280_S32_t variable
*/
static BME280_S32_t bme280_parse_press_temp_s32t(uint8_t *raw);
/**
* @brief convert buffer to single variable
*
* Function converts raw adc values of humidity to single #BME280_S32_t variable
*/
static BME280_S32_t bme280_parse_hum_s32t(uint8_t *raw);
/**
* @brief compensate temperature value
*
* Function returns compensated temperature in DegC, resolution is 0.01 DegC. Output value of “5123”
* equals 51.23 DegC. It calculates t_fine variable stored inside *Dev structure as well.
*/
static BME280_S32_t bme280_compensate_t_s32t(BME280_t *Dev, BME280_S32_t adc_T);
/**
* @brief compensate pressure value
*
* Function returns compensated pressure in Pa as unsigned 32 bit integer. Output value depends of #USE_64BIT
* configuration.
*/
static BME280_U32_t bme280_compensate_p_u32t(BME280_t *Dev, BME280_S32_t adc_P);
/**
* @brief compensate humidity value
*
* Function returns compensated humidity in %RH as unsigned 32bit integer. Output value of "47445"
* represents 47445/1000 = 47.445 %RH
*/
static BME280_U32_t bme280_compensate_h_u32t(BME280_t *Dev, BME280_S32_t adc_H);
#ifdef USE_INTEGER_RESULTS
/**
* @brief convert temperature to structure
*
* Function converts temperature stored in #BME280_S32_t to #BME280_Data_t structure
*/
static void bme280_convert_t_S32_struct(BME280_S32_t temp, BME280_Data_t *data);
#endif
#ifdef USE_FLOATS_RESULTS
/**
* @brief convert temperature to float
*
* Function converts temperature stored in #BME280_S32_t to float variable
*/
static void bme280_convert_t_S32_float(BME280_S32_t temp_in, float *temp_out);
#endif
#ifdef USE_INTEGER_RESULTS
/**
* @brief convert pressure to structure
*
* Function converts pressure stored in #BME280_U32_t to #BME280_Data_t structure
*/
static void bme280_convert_p_U32_struct(BME280_U32_t press, BME280_Data_t *data);
#endif
#ifdef USE_FLOATS_RESULTS
/**
* @brief convert pressure to structure
*
* Function converts pressure stored in #BME280_U32_t to float variable
*/
static void bme280_convert_p_U32_float(BME280_U32_t press_in, float *press_out);
#endif
#ifdef USE_INTEGER_RESULTS
/**
* @brief convert humidity to structure
*
* Function converts humidity stored in #BME280_U32_t to #BME280_Data_t structure
*/
static void bme280_convert_h_U32_struct(BME280_U32_t hum, BME280_Data_t *data);
#endif
#ifdef USE_FLOATS_RESULTS
/**
* @brief convert humidity to structure
*
* Function converts humidity stored in #BME280_U32_t to float variable
*/
static void bme280_convert_h_U32_float(BME280_U32_t hum_in, float *hum_out);
#endif
#ifdef USE_NORMAL_MODE
/**
* @brief check for normal mode
*
* Function checks if device is initializes and if it's status in *Dev structure
* is set as "normal_mode"
*/
static int8_t bme280_is_normal_mode(BME280_t *Dev);
#endif
/**
* @brief check for sleep mode
*
* Function checks if device is initializes and if it's status in *Dev structure
* is set as "sleep_mode"
*/
static int8_t bme280_is_sleep_mode(BME280_t *Dev);
#ifdef USE_FORCED_MODE
/**
* @brief check and set forced mode
*
* Function checks if conditions to set forced mode are met, calculates and returns required
* delay time (via *delay pointer) then sets forced mode
*/
static int8_t bme280_set_forced_mode(BME280_t *Dev, uint8_t *delay);
/**
* @brief change osrs_x reg value to oversampling
*
* Function converts register value to oversampling value
* f.e. osrs_p = 0x04 then pressure oversampling = x8
*/
static void bme280_osrs_to_oversampling(uint8_t *osrs);
/**
* @brief check if sensor is busy
*
* Function reads "status" register and checks value of two its bits
* returns #BME280_BUSY_ERR if any of them is set
*/
static int8_t bme280_busy_check(BME280_t *Dev);
#endif
///@}
///@}
//***************************************
/* public functions */
//***************************************
/* function that initiates minimum required parameters to operate with a sensor */
int8_t BME280_Init(BME280_t *Dev, BME280_Driver_t *Driver){
int8_t res = BME280_OK;
uint8_t id = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(Driver) || IS_NULL(Driver->write) || IS_NULL(Driver->read) ||
IS_NULL(Driver->delay) ) return BME280_PARAM_ERR;
/* attach the driver to main structure */
Dev->driver = Driver;
/* perform sensor reset */
res = BME280_Reset(Dev);
if(BME280_OK != res) return res;
/* Start-up time = 2ms */
Dev->driver->delay(2);
/* read and check chip ID */
res = Dev->driver->read(BME280_ID_ADDR, &id, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
if(BME280_ID != id) return BME280_ID_ERR;
/* read, parse and store compensation data */
res = bme280_read_compensation_parameters(Dev);
if(BME280_OK == res) Dev->initialized = initialized;
return res;
}
/* Function configures all sensor parameters at once */
int8_t BME280_ConfigureAll(BME280_t *Dev, BME280_Config_t *Config){
int8_t res = BME280_OK;
uint8_t ctrl_hum = 0, ctrl_meas = 0, config = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(Config) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* set the data from Config structure to the right positions in
* sensor registers */
ctrl_hum = Config->oversampling_h & 0x07; //0x07 - 0b00000111
ctrl_meas |= (Config->oversampling_t << 5) & 0xE0; //0xE0 - 0b11100000
ctrl_meas |= (Config->oversampling_p << 2) & 0x1C; //0x1C - 0b00011100
ctrl_meas |= Config->mode & 0x03; //0x03 - 0b00000011
config |= (Config->t_stby << 5) & 0xE0; //0xE0 - 0b11100000
config |= (Config->filter << 2) & 0x1C; //0x1C - 0b00011100
config |= Config->spi3w_enable & 0x01; //0x01 - 0b00000001
/* send three config bytes to the device */
res = Dev->driver->write(BME280_CTRL_HUM_ADDR, ctrl_hum, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
res = Dev->driver->write(BME280_CTRL_MEAS_ADDR, ctrl_meas, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
res = Dev->driver->write(BME280_CONFIG_ADDR, config, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* set oparing mode inside Dev structure */
if(BME280_SLEEPMODE == Config->mode){
Dev->mode = sleep_mode;
}
else if(BME280_FORCEDMODE == Config->mode){
Dev->mode = forced_mode;
}
else if(BME280_NORMALMODE == Config->mode){
Dev->mode = normal_mode;
}
return res;
}
/* function performs power-on reset procedure for sensor */
int8_t BME280_Reset(BME280_t *Dev){
int8_t res = BME280_OK;
/* check parameter */
if( IS_NULL(Dev) || IS_NULL(Dev->driver->write) ) return BME280_PARAM_ERR;
/* write reset commad to reset register */
res = Dev->driver->write(BME280_RESET_ADDR, BME280_RESET_VALUE, Dev->driver);
/* set mode to default */
Dev->mode = sleep_mode;
return res;
}
#ifdef USE_GETTERS
/* Function reads current operation mode from sensor */
int8_t BME280_GetMode(BME280_t *Dev, uint8_t *Mode){
int8_t res = BME280_OK;
uint8_t ctrl_meas = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(Mode) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of ctrl_meas register from sensor */
res = Dev->driver->read(BME280_CTRL_MEAS_ADDR, &ctrl_meas, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* parse mode values from ctrl_meas */
ctrl_meas &= 0x03;
if(0x02 == ctrl_meas) ctrl_meas = BME280_FORCEDMODE;
/* update value inside Dev structure */
Dev->mode = ctrl_meas;
/* set output pointer */
*Mode = ctrl_meas;
return res;
}
/* function gets current pressure oversampling value from sensor */
int8_t BME280_GetPOvs(BME280_t *Dev, uint8_t *POvs){
int8_t res = BME280_OK;
uint8_t ctrl_meas = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(POvs) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of ctrl_meas register from sensor */
res = Dev->driver->read(BME280_CTRL_MEAS_ADDR, &ctrl_meas, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* parse pressure oversampling value from ctrl_meas */
ctrl_meas = (ctrl_meas >> 2) & 0x07;
/* set output pointer */
*POvs = ctrl_meas;
return res;
}
/* function gets current temperature oversampling value from sensor */
int8_t BME280_GetTOvs(BME280_t *Dev, uint8_t *TOvs){
int8_t res = BME280_OK;
uint8_t ctrl_meas = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(TOvs) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of ctrl_meas register from sensor */
res = Dev->driver->read(BME280_CTRL_MEAS_ADDR, &ctrl_meas, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* parse temperature oversampling value from ctrl_meas */
ctrl_meas = (ctrl_meas >> 5) & 0x07;
/* set output pointer */
*TOvs = ctrl_meas;
return res;
}
/* function gets current humidity oversampling value from sensor */
int8_t BME280_GetHOvs(BME280_t *Dev, uint8_t *HOvs){
int8_t res = BME280_OK;
uint8_t ctrl_hum = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(HOvs) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of ctrl_hum register from sensor */
res = Dev->driver->read(BME280_CTRL_HUM_ADDR, &ctrl_hum, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* parse humidity oversampling value from ctrl_hum */
ctrl_hum = ctrl_hum & 0x07;
/* set output pointer */
*HOvs = ctrl_hum;
return res;
}
/* function gets current standby time for normal mode */
int8_t BME280_GetTStby(BME280_t *Dev, uint8_t *TStby){
int8_t res = BME280_OK;
uint8_t config = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(TStby) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of config register from sensor */
res = Dev->driver->read(BME280_CONFIG_ADDR, &config, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* parse standby time value from config */
config = (config >> 5) & 0x07;
/* set output pointer */
*TStby = config;
return res;
}
/* function gets current value of IIR filter */
int8_t BME280_GetTFilter(BME280_t *Dev, uint8_t *Filter){
int8_t res = BME280_OK;
uint8_t config = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(Filter) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of config register from sensor */
res = Dev->driver->read(BME280_CONFIG_ADDR, &config, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* parse filter value from config */
config = (config >> 2) & 0x07;
/* set output pointer */
*Filter = config;
return res;
}
/* function reads current 3-wire SPI setup (0 = 3w SPI disabled, 1 - 3w SPI enabled) */
int8_t BME280_Is3WireSPIEnabled(BME280_t *Dev, uint8_t *Result){
int8_t res = BME280_OK;
uint8_t config = 0;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(Result) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of ctrl_meas register from sensor */
res = Dev->driver->read(BME280_CONFIG_ADDR, &config, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* parse mode values from ctrl_meas */
config &= 0x01;
/* set output pointer */
*Result = config;
return res;
}
#endif
#ifdef USE_SETTERS
/* Function sets sensor operation mode */
int8_t BME280_SetMode(BME280_t *Dev, uint8_t Mode){
int8_t res = BME280_OK;
uint8_t ctrl_meas = 0, tmp = 0;
/* check parameters */
if( IS_NULL(Dev) || (Mode > BME280_NORMALMODE) ) return BME280_PARAM_ERR;
/* check if sensor is initialized */
res = bme280_is_sleep_mode(Dev);
if(BME280_NO_INIT_ERR == res) return res;
/* read value of ctrl_meas register from sensor */
res = Dev->driver->read(BME280_CTRL_MEAS_ADDR, &ctrl_meas, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* check if current mode differs from requested */
tmp = ctrl_meas & 0x03;
if(0x02 == tmp) tmp = BME280_FORCEDMODE;
if(Mode == tmp) return BME280_OK;
/* send new ctrl_meas value to sensor if required */
ctrl_meas &= 0xFC; //0xFC - 0b11111100
ctrl_meas |= Mode;
res = Dev->driver->write(BME280_CTRL_MEAS_ADDR, ctrl_meas, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* update value inside Dev structure */
Dev->mode = Mode;
return res;
}
/* function sets pressure oversampling value */
int8_t BME280_SetPOvs(BME280_t *Dev, uint8_t POvs){
int8_t res = BME280_OK;
uint8_t ctrl_meas = 0, tmp = 0;
/* check parameters */
if( IS_NULL(Dev) || (POvs > BME280_OVERSAMPLING_X16) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* read value of ctrl_meas register from sensor */
res = Dev->driver->read(BME280_CTRL_MEAS_ADDR, &ctrl_meas, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* check if current value differs from requested */
tmp = (ctrl_meas >> 2) & 0x07;
if(POvs == tmp) return BME280_OK;
/* send new ctrl_meas value to sensor if required */
ctrl_meas &= 0xE3; //0xE3 - 0b11100011
ctrl_meas |= (POvs << 2);
res = Dev->driver->write(BME280_CTRL_MEAS_ADDR, ctrl_meas, Dev->driver);
return res;
}
/* function sets temperature oversampling value */
int8_t BME280_SetTOvs(BME280_t *Dev, uint8_t TOvs){
int8_t res = BME280_OK;
uint8_t ctrl_meas = 0, tmp = 0;
/* check parameters */
if( IS_NULL(Dev) || (TOvs > BME280_OVERSAMPLING_X16) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* read value of ctrl_meas register from sensor */
res = Dev->driver->read(BME280_CTRL_MEAS_ADDR, &ctrl_meas, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* check if current value differs from requested */
tmp = (ctrl_meas >> 5) & 0x07;
if(TOvs == tmp) return BME280_OK;
/* send new ctrl_meas value to sensor if required */
ctrl_meas &= 0x1F; //0x1F - 0b00011111
ctrl_meas |= (TOvs << 5);
res = Dev->driver->write(BME280_CTRL_MEAS_ADDR, ctrl_meas, Dev->driver);
return res;
}
/* function sets humidity oversampling value */
int8_t BME280_SetHOvs(BME280_t *Dev, uint8_t HOvs){
int8_t res = BME280_OK;
uint8_t tmp = 0;
/* check parameters */
if( IS_NULL(Dev) || (HOvs > BME280_OVERSAMPLING_X16) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* send requested value to sensor */
res = Dev->driver->write(BME280_CTRL_HUM_ADDR, HOvs, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* to make the change effective we need to write ctrl_meas register,
* check documentation */
res = Dev->driver->read(BME280_CTRL_MEAS_ADDR, &tmp, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
res = Dev->driver->write(BME280_CTRL_MEAS_ADDR, tmp, Dev->driver);
return res;
}
/* function sets standby time */
int8_t BME280_SetTStby(BME280_t *Dev, uint8_t TStby){
int8_t res = BME280_OK;
uint8_t config = 0, tmp = 0;
/* check parameters */
if( IS_NULL(Dev) || (TStby > BME280_STBY_20MS) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* read value of config register from sensor */
res = Dev->driver->read(BME280_CONFIG_ADDR, &config, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* check if current value differs from requested */
tmp = (config >> 5) & 0x07;
if(TStby == tmp) return BME280_OK;
/* send new config value to sensor if required */
config &= 0x1F; //0x1F - 0b00011111
config |= (TStby << 5);
res = Dev->driver->write(BME280_CONFIG_ADDR, config, Dev->driver);
return res;
}
/* function sets IIR filter value */
int8_t BME280_SetFilter(BME280_t *Dev, uint8_t Filter){
int8_t res = BME280_OK;
uint8_t config = 0, tmp = 0;
/* check parameters */
if( IS_NULL(Dev) || (Filter > BME280_FILTER_16) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* read value of config register from sensor */
res = Dev->driver->read(BME280_CONFIG_ADDR, &config, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* check if current value differs from requested */
tmp = (config >> 2) & 0x07;
if(Filter == tmp) return BME280_OK;
/* send new config value to sensor if required */
config &= 0xE3; //0xE3 - 0b11100011
config |= (Filter << 2);
res = Dev->driver->write(BME280_CONFIG_ADDR, config, Dev->driver);
return res;
}
/* function enables 3-wire SPI interface */
int8_t BME280_Enable3WireSPI(BME280_t *Dev){
int8_t res = BME280_OK;
uint8_t config = 0, tmp = 0;
/* check parameter */
if( IS_NULL(Dev) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* read value of config register from sensor */
res = Dev->driver->read(BME280_CONFIG_ADDR, &config, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* check if current value differs from requested */
tmp = config & 0x01;
if(0x01 == tmp) return BME280_OK;
/* send new config value to sensor if required */
config &= 0xFE; //0xFE - 0b11111110
config |= 0x01;
res = Dev->driver->write(BME280_CONFIG_ADDR, config, Dev->driver);
return res;
}
/* function disables 3-wire SPI interface */
int8_t BME280_Disable3WireSPI(BME280_t *Dev){
int8_t res = BME280_OK;
uint8_t config = 0, tmp = 0;
/* check parameter */
if( IS_NULL(Dev) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* read value of config register from sensor */
res = Dev->driver->read(BME280_CONFIG_ADDR, &config, 1, Dev->driver);
if(BME280_OK != res) return BME280_INTERFACE_ERR;
/* check if current value differs from requested */
tmp = config & 0x01;
if(0x00 == tmp) return BME280_OK;
/* send new config value to sensor if required */
config &= 0xFE; //0xFE - 0b11111110
res = Dev->driver->write(BME280_CONFIG_ADDR, config, Dev->driver);
return res;
}
#endif
#ifdef USE_INTEGER_RESULTS
#ifdef USE_NORMAL_MODE
/* function reads last measured values from sensor in normal mode (no floats) */
int8_t BME280_ReadAllLast(BME280_t *Dev, BME280_Data_t *Data){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_U32_t press, hum;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(Data) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in normal mode */
res = bme280_is_normal_mode(Dev);
if(BME280_OK != res) return res;
/* read the data from sensor */
res = bme280_read_compensate(read_all, Dev, &temp, &press, &hum);
if(BME280_OK != res) return res;
/* convert 32bit values to Data structure */
bme280_convert_t_S32_struct(temp, Data);
bme280_convert_p_U32_struct(press, Data);
bme280_convert_h_U32_struct(hum, Data);
return res;
}
/* function reads last measured temperature from sensor in normal mode (no floats) */
int8_t BME280_ReadTempLast(BME280_t *Dev, int8_t *TempInt, uint8_t *TempFract){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_Data_t data;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(TempInt) || IS_NULL(TempFract) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in normal mode */
res = bme280_is_normal_mode(Dev);
if(BME280_OK != res) return res;
/* read the data from sensor */
res = bme280_read_compensate(read_temp, Dev, &temp, 0, 0);
if(BME280_OK != res) return res;
/* convert 32bit values to local data structure */
bme280_convert_t_S32_struct(temp, &data);
/* set values of external variables */
*TempInt = data.temp_int;
*TempFract = data.temp_fract;
return res;
}
/* function reads last measured pressure from sensor in normal mode (no floats) */
int8_t BME280_ReadPressLast(BME280_t *Dev, uint16_t *PressInt, uint16_t *PressFract){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_U32_t press;
BME280_Data_t data;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(PressInt) || IS_NULL(PressFract) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in normal mode */
res = bme280_is_normal_mode(Dev);
if(BME280_OK != res) return res;
/* read the data from sensor */
res = bme280_read_compensate(read_press, Dev, &temp, &press, 0);
if(BME280_OK != res) return res;
/* convert 32bit value to local data structure */
bme280_convert_p_U32_struct(press, &data);
/* set values of external variables */
*PressInt = data.pressure_int;
*PressFract = data.pressure_fract;
return res;
}
/* function reads last measured humidity from sensor in normal mode (no floats) */
int8_t BME280_ReadHumLast(BME280_t *Dev, uint8_t *HumInt, uint16_t *HumFract){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_U32_t hum;
BME280_Data_t data;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(HumInt) || IS_NULL(HumFract) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in normal mode */
res = bme280_is_normal_mode(Dev);
if(BME280_OK != res) return res;
/* read the data from sensor */
res = bme280_read_compensate(read_hum, Dev, &temp, 0, &hum);
if(BME280_OK != res) return res;
/* convert 32bit value to local data structure */
bme280_convert_h_U32_struct(hum, &data);
/* set values of external variables */
*HumInt = data.humidity_int;
*HumFract = data.humidity_fract;
return res;
}
#endif
#ifdef USE_FORCED_MODE
/* function forces single measurement and reads all data (no floats) */
int8_t BME280_ReadAllForce(BME280_t *Dev, BME280_Data_t *Data){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_U32_t press, hum;
uint8_t delay;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(Data) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* force single measure */
res = bme280_set_forced_mode(Dev, &delay);
if(BME280_OK != res) return res;
/* wait until it ends */
Dev->driver->delay(delay);
/* check if measure is completed */
res = bme280_busy_check(Dev);
if(BME280_OK != res) return res;
/* read the data from sensor */
res = bme280_read_compensate(read_all, Dev, &temp, &press, &hum);
if(BME280_OK != res) return res;
/* convert 32bit values to Data structure */
bme280_convert_t_S32_struct(temp, Data);
bme280_convert_p_U32_struct(press, Data);
bme280_convert_h_U32_struct(hum, Data);
return res;
}
/* function forces single measurement and reads the temperature (no floats) */
int8_t BME280_ReadTempForce(BME280_t *Dev, int8_t *TempInt, uint8_t *TempFract){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_Data_t data;
uint8_t delay;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(TempInt) || IS_NULL(TempFract) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* force single measure */
res = bme280_set_forced_mode(Dev, &delay);
if(BME280_OK != res) return res;
/* wait until it ends */
Dev->driver->delay(delay);
/* check if measure is completed */
res = bme280_busy_check(Dev);
if(BME280_OK != res) return res;
/* read the data from sensor */
res = bme280_read_compensate(read_temp, Dev, &temp, 0, 0);
if(BME280_OK != res) return res;
/* convert 32bit values to local data structure */
bme280_convert_t_S32_struct(temp, &data);
/* set values of external variables */
*TempInt = data.temp_int;
*TempFract = data.temp_fract;
return res;
}
/* function forces single measurement and reads the pressure (no floats) */
int8_t BME280_ReadPressForce(BME280_t *Dev, uint16_t *PressInt, uint16_t *PressFract){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_U32_t press;
BME280_Data_t data;
uint8_t delay;
/* check parameters */
if( IS_NULL(Dev) || IS_NULL(PressInt) || IS_NULL(PressFract) ) return BME280_PARAM_ERR;
/* check if sensor is initialized and in sleep mode */
res = bme280_is_sleep_mode(Dev);
if(BME280_OK != res) return res;
/* force single measure */
res = bme280_set_forced_mode(Dev, &delay);
if(BME280_OK != res) return res;
/* wait until it ends */
Dev->driver->delay(delay);
/* check if measure is completed */
res = bme280_busy_check(Dev);
if(BME280_OK != res) return res;
/* read the data from sensor */
res = bme280_read_compensate(read_press, Dev, &temp, &press, 0);
if(BME280_OK != res) return res;
/* convert 32bit value to local data structure */
bme280_convert_p_U32_struct(press, &data);
/* set values of external variables */
*PressInt = data.pressure_int;
*PressFract = data.pressure_fract;
return res;
}
/* function forces single measurement and reads the humidity (no floats) */
int8_t BME280_ReadHumForce(BME280_t *Dev, uint8_t *HumInt, uint16_t *HumFract){
int8_t res = BME280_OK;
BME280_S32_t temp;
BME280_U32_t hum;