ButtonController.ino

#include <Keypad.h>
#include "Keyboard.h"

const byte ROWS = 2;
const byte COLS = 4;
// Define the Keymap
char keys[ROWS][COLS] = {
  {'1','2','3','4'},
  {'5','6','7','8'}
};

byte rowPins[ROWS] = { 10, 16 }; 
byte colPins[COLS] = { 6, 7, 8, 9 };

Keypad kpd = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

void setup() {
  Serial.begin(9600);
}

void loop() {
 char key = kpd.getKey();
  if(key)  // Check for a valid key.
  {
    Serial.println(key);
    switch (key)
    {
      case '1':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F1);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      case '2':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F2);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      case '3':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F3);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      case '4':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F4);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      case '5':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F5);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      case '6':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F6);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      case '7':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F7);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      case '8':
        Keyboard.begin();
        Keyboard.press(KEY_LEFT_CTRL);
        Keyboard.press(KEY_LEFT_ALT);
        Keyboard.press(KEY_F8);
        delay(100);
        Keyboard.releaseAll();
        Keyboard.end();
        break;
      default:
        Serial.println("Key Not Defined");
    }
  }
}