Line data    Source code

       1             : /* ✔ */
       2             : 
       3             : #pragma once
       4             : 
       5             : #include <AH/Settings/Warnings.hpp>
       6             : AH_DIAGNOSTIC_WERROR() // Enable errors on warnings
       7             : 
       8             : #include <AH/Hardware/Hardware-Types.hpp>
       9             : 
      10             : BEGIN_AH_NAMESPACE
      11             : 
      12             : /**
      13             :  * @brief   A class that reads the states of a button matrix.
      14             :  *
      15             :  * @tparam  nb_rows
      16             :  *          The number of rows in the button matrix.
      17             :  * @tparam  nb_cols
      18             :  *          The number of columns in the button matrix.
      19             :  * 
      20             :  * @ingroup AH_HardwareUtils
      21             :  */
      22             : template <uint8_t nb_rows, uint8_t nb_cols>
      23             : class ButtonMatrix {
      24             :   public:
      25             :     /**
      26             :      * @brief   Construct a new ButtonMatrix object.
      27             :      *
      28             :      * @param   rowPins
      29             :      *          A list of pin numbers connected to the rows of the button
      30             :      *          matrix.  
      31             :      *          **⚠** These pins will be driven LOW as outputs (Lo-Z).
      32             :      * @param   colPins
      33             :      *          A list of pin numbers connected to the columns of the button
      34             :      *          matrix.  
      35             :      *          These pins will be used as inputs (Hi-Z), and the internal 
      36             :      *          pull-up resistor will be enabled.
      37             :      */
      38             :     ButtonMatrix(const PinList<nb_rows> &rowPins,
      39             :                  const PinList<nb_cols> &colPins);
      40             :     /**
      41             :      * @brief   Destructor.
      42             :      */
      43           9 :     virtual ~ButtonMatrix() = default;
      44             : 
      45             :     /**
      46             :      * @brief   Initialize (enable internal pull-up resistors on column pins).
      47             :      */
      48             :     void begin();
      49             : 
      50             :     /**
      51             :      * @brief   Scan the matrix, read all button states, and call the
      52             :      *          onButtonChanged callback.
      53             :      */
      54             :     void update();
      55             : 
      56             :     /** 
      57             :      * Get the state of the button in the given column and row.
      58             :      * 
      59             :      * @note    No bounds checking is performed.
      60             :      */
      61             :     bool getPrevState(uint8_t col, uint8_t row);
      62             : 
      63             :   private:
      64             :     /**
      65             :      * @brief   The callback function that is called whenever a button changes
      66             :      *          state.
      67             :      * 
      68             :      * @param   row
      69             :      *          The row of the button that changed state.
      70             :      * @param   col
      71             :      *          The column of the button that changed state.
      72             :      * @param   state
      73             :      *          The new state of the button.
      74             :      */
      75             :     virtual void onButtonChanged(uint8_t row, uint8_t col, bool state) = 0;
      76             : 
      77             :     static inline uint8_t positionToBits(uint8_t col, uint8_t row);
      78             :     static inline uint8_t bitsToIndex(uint8_t bits);
      79             :     static inline uint8_t bitsToBitmask(uint8_t bits);
      80             :     void setPrevState(uint8_t col, uint8_t row, bool state);
      81             : 
      82             :     unsigned long prevRefresh = 0;
      83             :     uint8_t prevStates[(nb_cols * nb_rows + 7) / 8];
      84             : 
      85             :     const PinList<nb_rows> rowPins;
      86             :     const PinList<nb_cols> colPins;
      87             : };
      88             : 
      89             : END_AH_NAMESPACE
      90             : 
      91             : #include "ButtonMatrix.ipp" // Template implementations
      92             : 
      93             : AH_DIAGNOSTIC_POP()