Adafruit_Keypad.h

#ifndef _ADAFRUIT_KEYPAD_H_
#define _ADAFRUIT_KEYPAD_H_

#include "Adafruit_Keypad_Ringbuffer.h"
#include "Arduino.h"
#include <string.h>

#define makeKeymap(x) ((byte *)x) 

#define KEY_JUST_RELEASED (0) 
#define KEY_JUST_PRESSED (1)  

/**************************************************************************/
/**************************************************************************/
union keypadEvent {
  struct {
    uint8_t KEY : 8;   
    uint8_t EVENT : 8; 
    uint8_t ROW : 8;   
    uint8_t COL : 8;   
  } bit;               
  uint32_t reg;        
};

/**************************************************************************/
/**************************************************************************/
class Adafruit_Keypad {
public:
  Adafruit_Keypad(byte *userKeymap, byte *row, byte *col, int numRows,
                  int numCols);
  ~Adafruit_Keypad();
  void begin();

  void tick();

  bool justPressed(byte key, bool clear = true);
  bool justReleased(byte key);
  bool isPressed(byte key);
  bool isReleased(byte key);
  int available();
  keypadEvent read();
  void clear();

private:
  byte *_userKeymap;
  byte *_row;
  byte *_col;
  volatile byte *_keystates;
  Adafruit_Keypad_Ringbuffer _eventbuf;

  int _numRows;
  int _numCols;

  volatile byte *getKeyState(byte key);
};

#endif