hts221.c

00001 /**
00002  ******************************************************************************
00003  * @file    hts221.c
00004  * @author  MEMS Application Team
00005  * @version V1.0.0
00006  * @date    30-July-2014
00007  * @brief   This file provides a set of functions needed to manage the hts221.
00008  ******************************************************************************
00009  * @attention
00010  *
00011  * <h2><center>&copy; COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
00012  *
00013  * Redistribution and use in source and binary forms, with or without modification,
00014  * are permitted provided that the following conditions are met:
00015  *   1. Redistributions of source code must retain the above copyright notice,
00016  *      this list of conditions and the following disclaimer.
00017  *   2. Redistributions in binary form must reproduce the above copyright notice,
00018  *      this list of conditions and the following disclaimer in the documentation
00019  *      and/or other materials provided with the distribution.
00020  *   3. Neither the name of STMicroelectronics nor the names of its contributors
00021  *      may be used to endorse or promote products derived from this software
00022  *      without specific prior written permission.
00023  *
00024  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
00025  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00026  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
00027  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
00028  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
00029  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
00030  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
00031  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
00032  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
00033  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00034  *
00035  ******************************************************************************
00036  */
00037 /* Includes ------------------------------------------------------------------*/
00038 #include "hts221.h"
00039 #include <math.h>
00040 
00041 /** @addtogroup BSP
00042  * @{
00043  */
00044 
00045 /** @addtogroup STM32F439_SENSITRON
00046  * @{
00047  */
00048 
00049 /** @addtogroup HTS221
00050  * @{
00051  */
00052 
00053 
00054 /** @defgroup HTS221_Private_TypesDefinitions
00055  * @{
00056  */
00057 
00058 /**
00059  * @}
00060  */
00061 
00062 /** @defgroup HTS221_Private_Defines
00063  * @{
00064  */
00065 
00066 /**
00067  * @}
00068  */
00069 
00070 /** @defgroup HTS221_Private_Macros
00071  * @{
00072  */
00073 
00074 /**
00075  * @}
00076  */
00077 
00078 /** @defgroup HTS221_Private_Variables
00079  * @{
00080  */
00081 
00082 HUM_TEMP_DrvTypeDef Hts221Drv =
00083 {
00084  HTS221_Init,
00085  HTS221_Power_OFF,
00086  HTS221_ReadID,
00087  HTS221_RebootCmd,
00088  0,
00089  0,
00090  0,
00091  0,
00092  0,
00093  HTS221_GetHumidity,
00094  HTS221_GetTemperature
00095 };
00096 
00097 
00098 /* Temperature in degree for calibration  */
00099 float T0_degC, T1_degC;
00100 
00101 /* Output temperature value for calibration */
00102 int16_t T0_out, T1_out;
00103 
00104 
00105 /* Humidity for calibration  */
00106 float H0_rh, H1_rh;
00107 
00108 /* Output Humidity value for calibration */
00109 int16_t H0_T0_out, H1_T0_out;
00110 
00111 
00112 /**
00113  * @}
00114  */
00115 
00116 /** @defgroup HTS221_Private_FunctionPrototypes
00117  * @{
00118  */
00119 static void HTS221_Power_On(void);
00120 
00121 static void HTS221_Calibration(void);
00122 /**
00123  * @}
00124  */
00125 
00126 /** @defgroup HTS221_Private_Functions
00127  * @{
00128  */
00129 
00130 
00131 
00132 /**
00133  * @brief  HTS221 Calibration procedure.
00134  * @param  None
00135  * @retval None
00136  */
00137 static void HTS221_Calibration(void)
00138 {
00139     /* Temperature Calibration */
00140     /* Temperature in degree for calibration ( "/8" to obtain float) */
00141     uint16_t T0_degC_x8_L, T0_degC_x8_H, T1_degC_x8_L, T1_degC_x8_H;
00142     uint8_t H0_rh_x2, H1_rh_x2;
00143     uint8_t tempReg[2] = {0,0};
00144 
00145     HUM_TEMP_IO_Read(tempReg, HTS221_ADDRESS, HTS221_T0_degC_X8_ADDR, 1);
00146     T0_degC_x8_L = (uint16_t)tempReg[0];
00147 
00148     HUM_TEMP_IO_Read(tempReg, HTS221_ADDRESS, HTS221_T1_T0_MSB_X8_ADDR, 1);
00149     T0_degC_x8_H = (uint16_t) (tempReg[0] & 0x03);
00150 
00151     T0_degC = ((float)((T0_degC_x8_H<<8) | (T0_degC_x8_L)))/8;
00152 
00153     HUM_TEMP_IO_Read(tempReg, HTS221_ADDRESS, HTS221_T1_degC_X8_ADDR, 1);
00154     T1_degC_x8_L = (uint16_t)tempReg[0];
00155 
00156     HUM_TEMP_IO_Read(tempReg, HTS221_ADDRESS, HTS221_T1_T0_MSB_X8_ADDR, 1);
00157     T1_degC_x8_H = (uint16_t) (tempReg[0] & 0x0C);
00158     T1_degC_x8_H = T1_degC_x8_H >> 2;
00159 
00160     T1_degC = ((float)((T1_degC_x8_H<<8) | (T1_degC_x8_L)))/8;
00161 
00162     HUM_TEMP_IO_Read(tempReg, HTS221_ADDRESS, HTS221_T0_OUT_L_ADDR + 0x80, 2);
00163     T0_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);
00164 
00165     HUM_TEMP_IO_Read(tempReg, HTS221_ADDRESS, HTS221_T1_OUT_L_ADDR + 0x80, 2);
00166     T1_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);
00167 
00168     /* Humidity Calibration */
00169     /* Humidity in degree for calibration ( "/2" to obtain float) */
00170 
00171     HUM_TEMP_IO_Read(&H0_rh_x2, HTS221_ADDRESS, HTS221_H0_RH_X2_ADDR, 1);
00172 
00173     HUM_TEMP_IO_Read(&H1_rh_x2, HTS221_ADDRESS, HTS221_H1_RH_X2_ADDR, 1);
00174 
00175     HUM_TEMP_IO_Read(&tempReg[0], HTS221_ADDRESS, HTS221_H0_T0_OUT_L_ADDR + 0x80, 2);
00176     H0_T0_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);
00177 
00178     HUM_TEMP_IO_Read(&tempReg[0], HTS221_ADDRESS, HTS221_H1_T0_OUT_L_ADDR  + 0x80, 2);
00179     H1_T0_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);
00180 
00181     H0_rh = ((float)H0_rh_x2)/2;
00182     H1_rh = ((float)H1_rh_x2)/2;
00183 }
00184 
00185 
00186 /**
00187  * @brief  Set HTS221 Initialization.
00188  * @param  InitStruct: it contains the configuration setting for the HTS221.
00189  * @retval None
00190  */
00191 void HTS221_Init(HUM_TEMP_InitTypeDef *HTS221_Init)
00192 {  
00193     uint8_t tmp = 0x00;
00194 
00195     /* Configure the low level interface ---------------------------------------*/
00196     HUM_TEMP_IO_Init();
00197 
00198     HTS221_Power_On();
00199 
00200     HTS221_Calibration();
00201 
00202     HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00203 
00204     /* Output Data Rate selection */
00205     tmp &= ~(HTS221_ODR_MASK);
00206     tmp |= HTS221_Init->OutputDataRate;
00207 
00208     HUM_TEMP_IO_Write(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00209 }
00210 
00211 /**
00212  * @brief  Read ID address of HTS221
00213  * @param  Device ID address
00214  * @retval ID name
00215  */
00216 uint8_t HTS221_ReadID(void)
00217 {
00218     uint8_t tmp;
00219 
00220     /* Read WHO I AM register */
00221     HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_WHO_AM_I_ADDR, 1);
00222 
00223     /* Return the ID */
00224     return (uint8_t)tmp;
00225 }
00226 
00227 /**
00228  * @brief  Reboot memory content of HTS221
00229  * @param  None
00230  * @retval None
00231  */
00232 void HTS221_RebootCmd(void)
00233 {
00234     uint8_t tmpreg;
00235 
00236     /* Read CTRL_REG2 register */
00237     HUM_TEMP_IO_Read(&tmpreg, HTS221_ADDRESS, HTS221_CTRL_REG2_ADDR, 1);
00238 
00239     /* Enable or Disable the reboot memory */
00240     tmpreg |= HTS221_BOOT_REBOOTMEMORY;
00241 
00242     /* Write value to MEMS CTRL_REG2 regsister */
00243     HUM_TEMP_IO_Write(&tmpreg, HTS221_ADDRESS, HTS221_CTRL_REG2_ADDR, 1);
00244 }
00245 
00246 
00247 /**
00248  * @brief  Read HTS221 output register, and calculate the humidity.
00249  * @param  pfData : Data out pointer
00250  * @retval None
00251  */
00252 void HTS221_GetHumidity(float* pfData)
00253 {
00254     int16_t H_T_out, humidity_t;
00255     uint8_t tempReg[2] = {0,0};
00256     uint8_t tmp = 0x00;
00257     float H_rh;
00258     
00259     HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00260 
00261     /* Output Data Rate selection */
00262     tmp &= (HTS221_ODR_MASK);
00263     
00264     if(tmp == 0x00){
00265     
00266       HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG2_ADDR, 1);
00267 
00268       /* Serial Interface Mode selection */
00269       tmp &= ~(HTS221_ONE_SHOT_MASK);
00270       tmp |= HTS221_ONE_SHOT_START;
00271 
00272       HUM_TEMP_IO_Write(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG2_ADDR, 1);
00273     
00274       do{
00275       
00276         HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_STATUS_REG_ADDR, 1);
00277          
00278       }while(!(tmp&&0x02));
00279     
00280     }
00281     
00282     
00283     HUM_TEMP_IO_Read(&tempReg[0], HTS221_ADDRESS, HTS221_HUMIDITY_OUT_L_ADDR + 0x80, 2);
00284     H_T_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);
00285 
00286     H_rh = ((float)(H_T_out - H0_T0_out))/(H1_T0_out - H0_T0_out) * (H1_rh - H0_rh) + H0_rh;
00287 
00288     humidity_t = (uint16_t)(H_rh * pow(10,HUM_DECIMAL_DIGITS));
00289 
00290     *pfData = ((float)humidity_t)/pow(10,HUM_DECIMAL_DIGITS);
00291 }
00292 
00293 /**
00294  * @brief  Read HTS221 output register, and calculate the temperature.
00295  * @param  pfData : Data out pointer
00296  * @retval None
00297  */
00298 void HTS221_GetTemperature(float* pfData)
00299 {
00300     int16_t T_out, temperature_t;
00301     uint8_t tempReg[2] = {0,0};
00302     uint8_t tmp = 0x00;
00303     float T_degC;
00304     
00305     HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00306 
00307     /* Output Data Rate selection */
00308     tmp &= (HTS221_ODR_MASK);
00309     
00310     if(tmp == 0x00){
00311     
00312       HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG2_ADDR, 1);
00313 
00314       /* Serial Interface Mode selection */
00315       tmp &= ~(HTS221_ONE_SHOT_MASK);
00316       tmp |= HTS221_ONE_SHOT_START;
00317 
00318       HUM_TEMP_IO_Write(&tmp, HTS221_ADDRESS, HTS221_CTRL_REG2_ADDR, 1);
00319     
00320       do{
00321       
00322         HUM_TEMP_IO_Read(&tmp, HTS221_ADDRESS, HTS221_STATUS_REG_ADDR, 1);
00323        
00324       }while(!(tmp&&0x01));
00325     
00326     }
00327 
00328     HUM_TEMP_IO_Read(&tempReg[0], HTS221_ADDRESS, HTS221_TEMP_OUT_L_ADDR + 0x80, 2);
00329     T_out = ((((int16_t)tempReg[1]) << 8)+(int16_t)tempReg[0]);
00330 
00331     T_degC = ((float)(T_out - T0_out))/(T1_out - T0_out) * (T1_degC - T0_degC) + T0_degC;
00332 
00333     temperature_t = (int16_t)(T_degC * pow(10,TEMP_DECIMAL_DIGITS));
00334 
00335     *pfData = ((float)temperature_t)/pow(10,TEMP_DECIMAL_DIGITS);
00336 }
00337 
00338 
00339 /**
00340  * @brief  Exit the shutdown mode for HTS221.
00341  * @retval None
00342  */
00343 static void HTS221_Power_On()
00344 {
00345     uint8_t tmpReg;
00346 
00347     /* Read the register content */
00348     HUM_TEMP_IO_Read(&tmpReg, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00349 
00350     /* Set the power down bit */
00351     tmpReg |= HTS221_MODE_ACTIVE;
00352 
00353     /* Write register */
00354     HUM_TEMP_IO_Write(&tmpReg, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00355 }
00356 
00357 /**
00358  * @brief  Enter the shutdown mode for HTS221.
00359  * @retval None
00360  */
00361 void HTS221_Power_OFF()
00362 {
00363     uint8_t tmpReg;
00364 
00365     /* Read the register content */
00366     HUM_TEMP_IO_Read(&tmpReg, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00367 
00368     /* Reset the power down bit */
00369     tmpReg &= ~(HTS221_MODE_ACTIVE);
00370 
00371     /* Write register */
00372     HUM_TEMP_IO_Write(&tmpReg, HTS221_ADDRESS, HTS221_CTRL_REG1_ADDR, 1);
00373 }
00374 
00375 /**
00376  * @}
00377  */
00378 
00379 /**
00380  * @}
00381  */
00382 
00383 /**
00384  * @}
00385  */
00386 
00387 /**
00388  * @}
00389  */
00390 
00391 
00392 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/     
00393