File content as of revision 4:566f2c41dc1d:

/**
 ******************************************************************************
 * @file    hts221.cpp
 * @author  AST / EST
 * @version V0.0.1
 * @date    14-April-2015
 * @brief   Implementation file for the HTS221 driver class
 ******************************************************************************
 * @attention
 *
 * <h2><center>&copy; COPYRIGHT(c) 2015 STMicroelectronics</center></h2>
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *   1. Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *   2. Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *   3. Neither the name of STMicroelectronics nor the names of its contributors
 *      may be used to endorse or promote products derived from this software
 *      without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************
*/

/* betzw - based on:
           X-CUBE-MEMS1/trunk/Drivers/BSP/Components/hts221/hts221.c: revision #270,
           X-CUBE-MEMS1/trunk: revision #293
*/

/* Includes ------------------------------------------------------------------*/
#include "mbed.h"
#include "hts221_class.h"
#include "hts221.h"
#include "../../x_nucleo_iks01a1_targets.h"

/* Methods -------------------------------------------------------------------*/
/**
 * @brief  HTS221 Calibration procedure
 * @param  None
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_Calibration(void)
{
    /* Temperature Calibration */
    /* Temperature in degree for calibration ( "/8" to obtain float) */
    uint16_t T0_degC_x8_L, T0_degC_x8_H, T1_degC_x8_L, T1_degC_x8_H;
    uint8_t H0_rh_x2, H1_rh_x2;
    uint8_t tempReg[2] = {0,0};

    if(HTS221_IO_Read(tempReg, HTS221_T0_degC_X8_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    T0_degC_x8_L = (uint16_t)tempReg[0];

    if(HTS221_IO_Read(tempReg, HTS221_T1_T0_MSB_X8_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    T0_degC_x8_H = (uint16_t) (tempReg[0] & 0x03);
    T0_degC = ((float)((T0_degC_x8_H<<8) | (T0_degC_x8_L)))/8;

    if(HTS221_IO_Read(tempReg, HTS221_T1_degC_X8_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    T1_degC_x8_L = (uint16_t)tempReg[0];

    if(HTS221_IO_Read(tempReg, HTS221_T1_T0_MSB_X8_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    T1_degC_x8_H = (uint16_t) (tempReg[0] & 0x0C);
    T1_degC_x8_H = T1_degC_x8_H >> 2;
    T1_degC = ((float)((T1_degC_x8_H<<8) | (T1_degC_x8_L)))/8;

    if(HTS221_IO_Read(tempReg, (HTS221_T0_OUT_L_ADDR | HTS221_I2C_MULTIPLEBYTE_CMD), 2) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    T0_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);

    if(HTS221_IO_Read(tempReg, (HTS221_T1_OUT_L_ADDR | HTS221_I2C_MULTIPLEBYTE_CMD), 2) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    T1_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);

    /* Humidity Calibration */
    /* Humidity in degree for calibration ( "/2" to obtain float) */

    if(HTS221_IO_Read(&H0_rh_x2, HTS221_H0_RH_X2_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    if(HTS221_IO_Read(&H1_rh_x2, HTS221_H1_RH_X2_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    if(HTS221_IO_Read(&tempReg[0], (HTS221_H0_T0_OUT_L_ADDR | HTS221_I2C_MULTIPLEBYTE_CMD), 2) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    H0_T0_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);

    if(HTS221_IO_Read(&tempReg[0], (HTS221_H1_T0_OUT_L_ADDR  | HTS221_I2C_MULTIPLEBYTE_CMD), 2) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    H1_T0_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);

    H0_rh = ((float)H0_rh_x2)/2;
    H1_rh = ((float)H1_rh_x2)/2;
    
    return HUM_TEMP_OK;
}


/**
 * @brief  Set HTS221 Initialization
 * @param  HTS221_Init the configuration setting for the HTS221
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_Init(HUM_TEMP_InitTypeDef *HTS221_Init)
{  
    uint8_t tmp = 0x00;

    /* Configure the low level interface ---------------------------------------*/
    if(HTS221_IO_Init() != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    if(HTS221_Power_On() != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    if(HTS221_Calibration() != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    if(HTS221_IO_Read(&tmp, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    /* Output Data Rate selection */
    tmp &= ~(HTS221_ODR_MASK);
    tmp |= HTS221_Init->OutputDataRate;

    if(HTS221_IO_Write(&tmp, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    HTS221_IO_ITConfig();
    
    return HUM_TEMP_OK;
}

/**
 * @brief  Read ID address of HTS221
 * @param  ht_id the pointer where the ID of the device is stored
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_ReadID(uint8_t *ht_id)
{
    if(!ht_id)
    { 
      return HUM_TEMP_ERROR; 
    }
 
    return HTS221_IO_Read(ht_id, HTS221_WHO_AM_I_ADDR, 1);
}

/**
 * @brief  Reboot memory content of HTS221
 * @param  None
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_RebootCmd(void)
{
    uint8_t tmpreg;

    /* Read CTRL_REG2 register */
    if(HTS221_IO_Read(&tmpreg, HTS221_CTRL_REG2_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    /* Enable or Disable the reboot memory */
    tmpreg |= HTS221_BOOT_REBOOTMEMORY;

    /* Write value to MEMS CTRL_REG2 regsister */
    if(HTS221_IO_Write(&tmpreg, HTS221_CTRL_REG2_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    return HUM_TEMP_OK;
}


/**
 * @brief  Read HTS221 output register, and calculate the humidity
 * @param  pfData the pointer to data output
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_GetHumidity(float* pfData)
{
    int16_t H_T_out, humidity_t;
    uint8_t tempReg[2] = {0,0};
    uint8_t tmp = 0x00;
    float H_rh;
    
    if(HTS221_IO_Read(&tmp, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    /* Output Data Rate selection */
    tmp &= (HTS221_ODR_MASK);
    
    if(tmp == 0x00)
    {
      if(HTS221_IO_Read(&tmp, HTS221_CTRL_REG2_ADDR, 1) != HUM_TEMP_OK)
      {
        return HUM_TEMP_ERROR;
      }

      /* Serial Interface Mode selection */
      tmp &= ~(HTS221_ONE_SHOT_MASK);
      tmp |= HTS221_ONE_SHOT_START;

      if(HTS221_IO_Write(&tmp, HTS221_CTRL_REG2_ADDR, 1) != HUM_TEMP_OK)
      {
        return HUM_TEMP_ERROR;
      }
    
      do{
      
        if(HTS221_IO_Read(&tmp, HTS221_STATUS_REG_ADDR, 1) != HUM_TEMP_OK)
        {
          return HUM_TEMP_ERROR;
        }
         
      }while(!(tmp&&0x02));
    }
    
    
    if(HTS221_IO_Read(&tempReg[0], (HTS221_HUMIDITY_OUT_L_ADDR | HTS221_I2C_MULTIPLEBYTE_CMD), 2) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    H_T_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);

    H_rh = ( float )(((( H_T_out - H0_T0_out ) * ( H1_rh - H0_rh )) / ( H1_T0_out - H0_T0_out )) + H0_rh );

    // Truncate to specific number of decimal digits
    humidity_t = (uint16_t)(H_rh * pow(10,HUM_DECIMAL_DIGITS));
    *pfData = ((float)humidity_t)/pow(10,HUM_DECIMAL_DIGITS);
    
    // Prevent data going below 0% and above 100% due to linear interpolation
    if ( *pfData <   0.0f ) *pfData =   0.0f;
    if ( *pfData > 100.0f ) *pfData = 100.0f;
    
    return HUM_TEMP_OK;
}

/**
 * @brief  Read HTS221 output register, and calculate the temperature
 * @param  pfData the pointer to data output
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_GetTemperature(float* pfData)
{
    int16_t T_out, temperature_t;
    uint8_t tempReg[2] = {0,0};
    uint8_t tmp = 0x00;
    float T_degC;
    
    if(HTS221_IO_Read(&tmp, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    /* Output Data Rate selection */
    tmp &= (HTS221_ODR_MASK);
    
    if(tmp == 0x00)
    {
      if(HTS221_IO_Read(&tmp, HTS221_CTRL_REG2_ADDR, 1) != HUM_TEMP_OK)
      {
        return HUM_TEMP_ERROR;
      }

      /* Serial Interface Mode selection */
      tmp &= ~(HTS221_ONE_SHOT_MASK);
      tmp |= HTS221_ONE_SHOT_START;

      if(HTS221_IO_Write(&tmp, HTS221_CTRL_REG2_ADDR, 1) != HUM_TEMP_OK)
      {
        return HUM_TEMP_ERROR;
      }
    
      do{
      
        if(HTS221_IO_Read(&tmp, HTS221_STATUS_REG_ADDR, 1) != HUM_TEMP_OK)
        {
          return HUM_TEMP_ERROR;
        }
       
      }while(!(tmp&&0x01));
    }

    if(HTS221_IO_Read(&tempReg[0], (HTS221_TEMP_OUT_L_ADDR | HTS221_I2C_MULTIPLEBYTE_CMD), 2) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    T_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);

    T_degC = ((float)(T_out - T0_out))/(T1_out - T0_out) * (T1_degC - T0_degC) + T0_degC;

    temperature_t = (int16_t)(T_degC * pow(10,TEMP_DECIMAL_DIGITS));

    *pfData = ((float)temperature_t)/pow(10,TEMP_DECIMAL_DIGITS);
    
    return HUM_TEMP_OK;
}


/**
 * @brief  Exit the shutdown mode for HTS221
 * @param  None
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_Power_On(void)
{
    uint8_t tmpReg;

    /* Read the register content */
    if(HTS221_IO_Read(&tmpReg, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    /* Set the power down bit */
    tmpReg |= HTS221_MODE_ACTIVE;

    /* Write register */
    if(HTS221_IO_Write(&tmpReg, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    return HUM_TEMP_OK;
}

/**
 * @brief  Enter the shutdown mode for HTS221
 * @param  None
 * @retval HUM_TEMP_OK in case of success, an error code otherwise
 */
HUM_TEMP_StatusTypeDef HTS221::HTS221_Power_OFF(void)
{
    uint8_t tmpReg;

    /* Read the register content */
    if(HTS221_IO_Read(&tmpReg, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }

    /* Reset the power down bit */
    tmpReg &= ~(HTS221_MODE_ACTIVE);

    /* Write register */
    if(HTS221_IO_Write(&tmpReg, HTS221_CTRL_REG1_ADDR, 1) != HUM_TEMP_OK)
    {
      return HUM_TEMP_ERROR;
    }
    
    return HUM_TEMP_OK;
}