MPL3115A2.h

00001 /**
00002  * @file    MPL3115A2.h
00003  * @brief   Device driver - MPL3115A2 barometric pressure sensor IC w/RTOS support
00004  * @author  Tim Barr
00005  * @version 1.0
00006  * @see     http://cache.freescale.com/files/sensors/doc/data_sheet/MPL3115A2.pdf
00007  *
00008  * Copyright (c) 2015
00009  *
00010  * Licensed under the Apache License, Version 2.0 (the "License");
00011  * you may not use this file except in compliance with the License.
00012  * You may obtain a copy of the License at
00013  *
00014  *     http://www.apache.org/licenses/LICENSE-2.0
00015  *
00016  * Unless required by applicable law or agreed to in writing, software
00017  * distributed under the License is distributed on an "AS IS" BASIS,
00018  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00019  * See the License for the specific language governing permissions and
00020  * limitations under the License.
00021   */
00022  
00023 #ifndef MPL3115A2_H
00024 #define MPL3115A2_H
00025 
00026 #include "mbed.h"
00027 
00028 /** Using the MultiTech Systems MTDOT-EVB
00029  *
00030  * Example:
00031  * @code
00032  *  #include "mbed.h"
00033  *  #include "MPL3115A2.h"
00034  *
00035 
00036  * 
00037  *  int main() 
00038  *  {
00039 
00040  *  }
00041  * @endcode
00042  */
00043 
00044 
00045 /**
00046  *  @class MPL3115A2_DATA
00047  *  @brief API abstraction for the MPL3115A2 barometric pressure IC data
00048  */  
00049 class MPL3115A2_DATA
00050 {      
00051 public:
00052 /*!< volatile data variables */
00053     volatile int32_t _baro ;
00054     volatile int16_t _temp;
00055     volatile int32_t _minbaro;
00056     volatile int32_t _maxbaro;
00057     volatile int16_t _mintemp;
00058     volatile int16_t _maxtemp;
00059     
00060     /** Create the MPL3115A2_DATA object initialized to the parameter (or 0 if none)
00061      *  @param baro    - the init value of _baro
00062      *  @param temp    - the init value of _temperature
00063      *  @param minbaro - the init value of _minbaro
00064      *  @param maxbaro - the init value of _maxbaro
00065      *  @param mintemp - the init value of _mintemp
00066      *  @param maxtemp - the init value of _maxtemp
00067      */
00068     MPL3115A2_DATA(int32_t baro = 0, int16_t temp = 0, int32_t minbaro = 0, int32_t maxbaro = 0,
00069                     int16_t mintemp = 0, int16_t maxtemp = 0) : _baro (baro), _temp(temp), _minbaro(minbaro),
00070                     _maxbaro(maxbaro), _mintemp(mintemp), _maxtemp(maxtemp){}
00071     
00072     /** Overloaded '=' operator to allow shorthand coding, assigning objects to one another
00073      *  @param rhs - an object of the same type to assign ourself the same values of
00074      *  @return this
00075      */
00076     MPL3115A2_DATA &operator= (MPL3115A2_DATA  const &rhs)
00077     {
00078         _baro  = rhs._baro ;
00079         _temp = rhs._temp;
00080         _minbaro = rhs._minbaro;
00081         _maxbaro = rhs._maxbaro;
00082         _mintemp = rhs._mintemp;
00083         _maxtemp = rhs._maxtemp;
00084         
00085         return *this;
00086     }
00087     
00088     /** Overloaded '=' operator to allow shorthand coding, assigning objects to one another
00089      *  @param val - Assign each data member (_pressure, _temperature) this value
00090      *  @return this
00091 
00092     MPL3115A2_DATA &operator= (uint16_t   val)
00093     {
00094         _baro = _temp = val;
00095         
00096         return *this;
00097     }
00098     */
00099     
00100     /** Overloaded '==' operator to allow shorthand coding, test objects to one another
00101      *  @param rhs - the object to compare against
00102      *  @return 1 if the data members are the same and 0 otherwise
00103      */
00104     bool operator== (MPL3115A2_DATA   &rhs)
00105     {
00106         return ((_baro  == rhs._baro )&&(_temp == rhs._temp)&&
00107                 (_minbaro == rhs._minbaro) && (_maxbaro == rhs._maxbaro)&&
00108                 (_mintemp == rhs._mintemp) && (_maxtemp == rhs._maxtemp)) ? 1 : 0;
00109     }
00110 };
00111 
00112 /**
00113  *  @class MPL3115A2
00114  *  @brief API abstraction for the MPL3115A2 3-axis barometric sensor IC
00115  *  initial version will be polling only. Interrupt service and rtos support will
00116  *  be added at a later point
00117  */ 
00118 class MPL3115A2
00119 {  
00120 public:
00121     
00122    /**
00123      *  @enum WHO_AM_I_VAL
00124      *  @brief Device ID's that this class is compatible with
00125      */ 
00126     enum WHO_AM_I_VAL
00127     { 
00128         I_AM_MPL3115A2  = 0xc4, /*!< MPL3115A2 WHO_AM_I register content */
00129     };
00130 
00131     /**
00132      * @enum SYS_MODE
00133      * @brief operating mode of MPL3115A2
00134      */
00135     enum SYS_MODE
00136     {
00137         STANDBY = 0,
00138         ACTIVE
00139     };
00140 
00141     /**
00142      * @enum DR_STATUS_VALS
00143      * @brief flags for data overwrite and data ready
00144      */
00145     enum DR_STATUS_VALS
00146     {
00147         TDR   = 0x02,
00148         PDR   = 0x04,
00149         PTDR  = 0x08,
00150         TOW   = 0x20,
00151         POW   = 0x40,
00152         PTOW  = 0x80
00153     };
00154 
00155   /**
00156      * @enum OUTPUT_MODE
00157      * @brief Select whether data is raw or post-processed
00158      */
00159     enum OUTPUT_MODE
00160     {
00161         DATA_NORMAL = 0x00,
00162         DATA_RAW    = 0x40
00163     };
00164     
00165      /**
00166      *  @enum DATA_MODE
00167      *  @brief Sets the pressure measurement post- processing mode for the sensor
00168      */
00169     enum DATA_MODE
00170     {
00171         DM_BAROMETER = 0x00,
00172         DM_ALTIMETER = 0x80
00173     };
00174 
00175      /**
00176      * @enum OVERSAMPLE_RATIO
00177      * @brief values for oversample ratio
00178      * Note: sample time is 2.5 msec * ratio# i.e. OR_8 -> 2.5 * 8 = 20 msec
00179      */
00180     enum OVERSAMPLE_RATIO
00181     {
00182         OR_1   = 0x00,
00183         OR_2   = 0x08,
00184         OR_4   = 0x10,
00185         OR_8   = 0x18,
00186         OR_16  = 0x20,
00187         OR_32  = 0x28,
00188         OR_64  = 0x30,
00189         OR_128 = 0x38
00190     };
00191 
00192     /**
00193     * @enum ACQUISITION_TIMER
00194     * @brief in active mode this sets time between samples in seconds
00195     */
00196    enum ACQUISITION_TIMER
00197     {
00198         AT_1 = 0x00,
00199         AT_2, AT_4, AT_8, AT_16, AT_32, AT_64, AT_128, AT_256,
00200         AT_512, AT_1024, AT_2048, AT_4096, AT_8192, AT_16384, AT_32768
00201     };
00202 
00203     /**
00204      *  @enum REGISTER
00205      *  @brief The device register map
00206      */
00207     enum REGISTER
00208     {
00209         STATUS = 0x0,
00210         OUT_P_MSB, OUT_P_CSB, OUT_P_LSB, OUT_T_MSB, OUT_T_LSB, DR_STATUS,
00211         OUT_P_DELTA_MSB, OUT_P_DELTA_CSB, OUT_P_DELTA_LSB, OUT_T_DELTA_MSB, OUT_T_DELTA_LSB,
00212         WHO_AM_I, F_STATUS, F_DATA, F_SETUP, TIME_DLY, SYSMOD, INT_SOURCE,
00213         PT_DATA_CFG, BAR_IN_MSB, BAR_IN_LSB, P_ARM_MSB, P_ARM_LSB, T_ARM,
00214         P_ARM_WND_MSB, P_ARM_WND_LSB, T_ARM_WND,
00215         P_MIN_MSB, P_MIN_CSB, P_MIN_LSB, T_MIN_MSB, T_MIN_LSB,
00216         P_MAX_MSB, P_MAX_CSB, P_MAX_LSB, T_MAX_MSB, T_MAX_LSB,
00217         CTRL_REG1, CTRL_REG2, CTRL_REG3, CTRL_REG4, CTRL_REG5,
00218         OFF_P, OFF_T, OFF_H
00219     };
00220         
00221     /** Create the MPL3115A2 object
00222      *  @param i2c - A defined I2C object
00223      *  @param int1 - A defined InterruptIn object pointer. Default NULL for polling mode
00224      *  @param int2 - A defined InterruptIn object pointer. Default NULL for polling mode
00225      *  TODO - Need to add interrupt support
00226      */ 
00227     MPL3115A2(I2C &i2c, InterruptIn* int1 = NULL, InterruptIn* int2 = NULL);
00228     
00229     /** Test the Who am I register for valid ID
00230      *  @return Boolean true if valid device
00231      */
00232     bool testWhoAmI(void)  ;
00233 
00234     /** Setup the MPL3115A2 for standard barometric sensor read mode
00235      *  @out_mode - Turns Data post processing ON/OFF using the OUTPUT_MODE enum
00236      *  @data_mode - Sets Pressure or Altitude mode using the DATA_MODE enum
00237      *  @os_ratio - Sets the Oversample ration using the OVERSAMPLE_RATIO enum
00238      *  @measure_time - Sets the Aquisition time for Active mode using the ACQUISITION_TIMER enum
00239      *  @return status of command
00240      *
00241      *  This sets the resolution, range, data rate, oversample
00242      *  mode, hi and lo pass filter.
00243      */
00244     uint8_t setParameters(OUTPUT_MODE out_mode, DATA_MODE data_mode, OVERSAMPLE_RATIO os_ratio,
00245                             ACQUISITION_TIMER measure_time)  ;
00246 
00247     uint8_t enableFIFO(void)  ;
00248 
00249     /** Put the MPL3115A2 in the Standby mode
00250      *  @return status of command
00251      *  TODO - need to implement function
00252      */
00253     uint8_t standbyMode(void)  ;
00254 
00255     /** Put the MPL3115A2 in the active mode
00256      *  @return status of command
00257      */
00258     uint8_t activeMode(void)  ;
00259 
00260     /** Triggers the MPL3115A2 to take one measurement in Active or Standby mode
00261      *  @return status of command
00262      */
00263     uint8_t triggerOneShot(void)  ;
00264 
00265     /** Set the sea level equivalent pressure for Altitude mode
00266      *  @alti_calib - Value is Equivalent sea level pressure for measurement location (2 Pa resolution) 
00267      *  @return status byte
00268      */
00269      uint8_t setAltitudeCalib(int16_t alti_calib)  ;
00270 
00271     /** Clears all minimum and maximum data registers
00272      *  @return status of command
00273      */
00274     uint8_t clearMinMaxRegs(void)  ;
00275 
00276     /** Check the MPL3115A2 status register
00277      *  @return status byte
00278      */
00279     uint8_t getStatus(void)  ;
00280 
00281     /** Get the Pressure or Altitude data
00282      *  @return The last valid pressure based reading from the barometric sensor
00283      */
00284     int32_t getBaroData(void);
00285     
00286     /** Get the Temperature data
00287      *  @return The last valid temperature reading from the barometric sensor
00288      */
00289     int16_t getTempData(void);
00290 
00291     /** Get the Minimum Pressure or Altitude data
00292      *  @param Boolean TRUE clears the register after reading
00293      *  @return The Minimum Pressure or Altitude read since last cleared
00294      */
00295     int32_t getMinBaro(bool   clear_data);
00296 
00297     /** Get the Maximum Pressure or Altitude data
00298      *  @param Boolean true clears the register after reading
00299      *  @return The Maximum Pressure or Altitude read since last cleared
00300      */
00301     int32_t getMaxBaro(bool   clear_data);
00302 
00303     /** Get the Minimum Temperature data
00304        *  @param Boolean true clears the register after reading
00305        *  @return The Minimum temperature read since last cleared
00306        */
00307     int16_t getMinTemp(bool   clear_data);
00308     
00309     /** Get the Maximum Temperature data
00310      *  @param Boolean true clears the register after reading
00311      *  @return The Maximum temperature read since last cleared
00312      */
00313     int16_t getMaxTemp(bool   clear_data);
00314 
00315     /** Get the MP3115A2 data structure
00316      *  @param Boolean true clears all MIN/MAX registers after reading
00317      *  @return MPL3115A2_DATA structure
00318      */
00319     MPL3115A2_DATA getAllData(bool   clear_data);
00320     
00321  /* 
00322   * Need to add interrupt support code here when I get the chance
00323   */
00324 
00325     
00326 private:
00327     
00328     I2C                     *_i2c;
00329     InterruptIn             *_int1;
00330     InterruptIn             *_int2;
00331     MPL3115A2_DATA          _data;
00332     bool                    _polling_mode;
00333     uint8_t static const    _i2c_addr = (0x60 <<1);
00334     
00335     uint8_t init(void);
00336     
00337     /** Write to a register
00338      *  Note: most writes are only valid in stop mode
00339      *  @param reg - The register to be written
00340      *  @param data - The data to be written
00341      *  @param count - number of bytes to send, assumes 1 byte if not specified
00342      *  @return - status of command
00343      */
00344     uint8_t writeRegister(uint8_t reg, char* data, uint8_t count = 1);
00345     
00346     /** Read from a register
00347      *  @param reg - The register to read from
00348      *  @param data - buffer of data to be read
00349      *  @param count - number of bytes to send, assumes 1 byte if not specified
00350      *  @return - status of command
00351      */
00352     uint8_t readRegister(uint8_t reg, char* data, uint8_t count = 1);
00353 
00354 };
00355 
00356 #endif