Home | History | Annotate | Download | only in mpr121 
      1 /*
      2  * Author: Jon Trulson <jtrulson (at) ics.com>
      3  * Copyright (c) 2014 Intel Corporation.
      4  *
      5  * Permission is hereby granted, free of charge, to any person obtaining
      6  * a copy of this software and associated documentation files (the
      7  * "Software"), to deal in the Software without restriction, including
      8  * without limitation the rights to use, copy, modify, merge, publish,
      9  * distribute, sublicense, and/or sell copies of the Software, and to
     10  * permit persons to whom the Software is furnished to do so, subject to
     11  * the following conditions:
     12  *
     13  * The above copyright notice and this permission notice shall be
     14  * included in all copies or substantial portions of the Software.
     15  *
     16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     19  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
     20  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     21  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     22  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     23  */
     24 #pragma once
     25 
     26 #include <string>
     27 #include <mraa/i2c.hpp>
     28 
     29 #define MPR121_I2C_BUS     0
     30 #define MPR121_DEFAULT_I2C_ADDR    0x5a
     31 
     32 namespace upm {
     33   /**
     34    * @brief MPR121 Touch Sensor library
     35    * @defgroup mpr121 libupm-mpr121
     36    * @ingroup seeed i2c touch tsk
     37    */
     38   /**
     39    * @library mpr121
     40    * @sensor mpr121
     41    * @comname MPR121 Touch Sensor
     42    * @altname Grove I2C Touch Sensor
     43    * @type touch
     44    * @man seeed
     45    * @web http://www.seeedstudio.com/wiki/Grove_-_I2C_Touch_Sensor
     46    * @con i2c
     47    * @kit tsk
     48    *
     49    * @brief API for the MPR121 I2C Touch Sensor
     50    *
     51    * UPM module for the MPR121 touch sensor
     52    *
     53    * @image html mpr121.jpg
     54    * @snippet mpr121.cxx Interesting
     55    */
     56   class MPR121 {
     57   public:
     58     /**
     59      * MPR121 constructor
     60      *
     61      * @param bus I2C bus to use
     62      */
     63     MPR121(int bus, uint8_t address = MPR121_DEFAULT_I2C_ADDR);
     64 
     65     /**
     66      * MPR121 destructor
     67      * ~MPR121();
     68      * there is no need for the destructor
     69      **/
     70 
     71     /**
     72      * Sets up a default configuration, based on Application Note 3944
     73      * (AN3944):
     74      * http://cache.freescale.com/files/sensors/doc/app_note/AN3944.pdf
     75      *
     76      * After configuration, the sensor is left in the run state.
     77      *
     78      * @return True if configuration is successful
     79      */
     80     bool configAN3944();
     81 
     82     /**
     83      * Reads button states in the m_buttonStates member variable. Also,
     84      * sets the m_overCurrentFault variable if overcurrent is detected.
     85      */
     86     void readButtons();
     87 
     88     /**
     89      * Writes value(s) into registers
     90      *
     91      * @param reg Register location to start writing into
     92      * @param buffer Buffer for data storage
     93      * @param len Number of bytes to write
     94      * @return mraa::Result
     95      */
     96     mraa::Result writeBytes(uint8_t reg, uint8_t *buffer, int len);
     97 
     98     /**
     99      * Reads value(s) from registers
    100      *
    101      * @param reg Register location to start reading from
    102      * @param buffer Buffer for data storage
    103      * @param len Number of bytes to read
    104      */
    105     int readBytes(uint8_t reg, uint8_t *buffer, int len);
    106 
    107     /**
    108      * Button states
    109      */
    110     uint16_t m_buttonStates;
    111 
    112     /**
    113      * Overcurrent detected
    114      */
    115     bool m_overCurrentFault;
    116 
    117   private:
    118     mraa::I2c m_i2c;
    119     uint8_t m_addr;
    120   };
    121 }
    122 
    123 
    124