bme280_sensor.c

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#include "bme280_sensor.h"
 
#include "../../proto/sensor.h"
// #include "../../user_config.h"
 
#include <bme280_common.h>
 
static uint32_t period = 0;
 
static struct bme280_dev dev;
 
static struct bme280_settings settings;
 
BME280Status BME280Init(void) {
  int8_t rslt;
 
  /* Interface selection is to be updated as parameter
   * For I2C :  BME280_I2C_INTF
   * For SPI :  BME280_SPI_INTF
   */
  rslt = bme280_interface_selection(&dev, BME280_I2C_INTF);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  rslt = bme280_init(&dev);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  /* Always read the current settings before writing, especially when all the
   * configuration is not modified */
  rslt = bme280_get_sensor_settings(&settings, &dev);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  /* Configuring the over-sampling rate, filter coefficient and standby time */
  /* Overwrite the desired settings */
  settings.filter = BME280_FILTER_COEFF_OFF;
 
  /* Over-sampling rate for humidity, temperature and pressure */
  settings.osr_h = BME280_OVERSAMPLING_1X;
  settings.osr_p = BME280_OVERSAMPLING_1X;
  settings.osr_t = BME280_OVERSAMPLING_1X;
 
  /* Setting the standby time */
  settings.standby_time = BME280_STANDBY_TIME_0_5_MS;
 
  rslt = bme280_set_sensor_settings(BME280_SEL_ALL_SETTINGS, &settings, &dev);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  /* Always set the power mode after setting the configuration */
  rslt = bme280_set_sensor_mode(BME280_POWERMODE_FORCED, &dev);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  /* Calculate measurement time in microseconds */
  rslt = bme280_cal_meas_delay(&period, &settings);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  return rslt;
}
 
BME280Status BME280MeasureAll(BME280Data* data) {
  int8_t rslt = BME280_E_NULL_PTR;
  uint8_t status_reg;
 
  // trigger measurement
  rslt = bme280_set_sensor_mode(BME280_POWERMODE_FORCED, &dev);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  // check the status
  rslt = bme280_get_regs(BME280_REG_STATUS, &status_reg, 1, &dev);
  if (rslt != BME280_OK) {
    return rslt;
  }
 
  if (status_reg & BME280_STATUS_MEAS_DONE) {
    /* Measurement time delay given to read sample */
    dev.delay_us(period, dev.intf_ptr);
 
    /* Read compensated data */
    rslt = bme280_get_sensor_data(BME280_ALL, data, &dev);
    if (rslt != BME280_OK) {
      return rslt;
    }
  }
 
  // adjust based on defines
  // #ifndef BME280_DOUBLE_ENABLE
  //  data->temperature = data->temperature / 100;
  //  data->humidity = data->humidity / 1000;
  //  */
  //  data->temperature = data->temperature;
  //  data->humidity = data->humidity;
  // #endif
  //
  // #ifdef BME280_64BIT_ENABLE
  //  data->pressure = data->pressure / 100;
  // #endif
 
  return rslt;
}
 
uint8_t BME280MeasureTemperature(uint8_t* data, Metadata meta, uint32_t idx) {
  (void)idx;
 
  // read sensor
  BME280Data sens_data;
  BME280Status status = BME280MeasureAll(&sens_data);
  if (status != BME280_STATUS_OK) {
    return -1;
  }
 
  SensorStatus sen_status = SENSOR_OK;
  size_t data_len = 0;
 
  // temperature
  sen_status = EncodeDoubleMeasurement(meta, sens_data.temperature,
                                       SensorType_BME280_TEMP, data, &data_len);
  if (sen_status != SENSOR_OK) {
    return -1;
  }
 
  return data_len;
}
 
uint8_t BME280MeasurePressure(uint8_t* data, Metadata meta, uint32_t idx) {
  (void)idx;
 
  // read sensor
  BME280Data sens_data;
  BME280Status status = BME280MeasureAll(&sens_data);
  if (status != BME280_STATUS_OK) {
    return -1;
  }
 
  SensorStatus sen_status = SENSOR_OK;
  size_t data_len = 0;
 
  // pressure
  sen_status = EncodeDoubleMeasurement(
      meta, sens_data.pressure, SensorType_BME280_PRESSURE, data, &data_len);
  if (sen_status != SENSOR_OK) {
    return -1;
  }
 
  return data_len;
}
 
uint8_t BME280MeasureHumidity(uint8_t* data, Metadata meta, uint32_t idx) {
  (void)idx;
 
  // read sensor
  BME280Data sens_data;
  BME280Status status = BME280MeasureAll(&sens_data);
  if (status != BME280_STATUS_OK) {
    return -1;
  }
 
  SensorStatus sen_status = SENSOR_OK;
  size_t data_len = 0;
 
  // humidity
  sen_status = EncodeDoubleMeasurement(
      meta, sens_data.humidity, SensorType_BME280_HUMIDITY, data, &data_len);
  if (sen_status != SENSOR_OK) {
    return -1;
  }
 
  return data_len;
}