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This example is for Wiring version 1.0 build 0100+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

HelloKeypad by BREVIG http://alexanderbrevig.com
Demonstrates the simplest use of the matrix Keypad library.

    #include <Keypad.h>

    const byte ROWS = 4; //four rows
    const byte COLS = 3; //three columns
    char keys[ROWS][COLS] = {
      {'1','2','3'},
      {'4','5','6'},
      {'7','8','9'},
      {'#','0','*'}
    };
    byte rowPins[ROWS] = {5, 4, 3, 2}; //connect to the row pinouts of the keypad
    byte colPins[COLS] = {8, 7, 6}; //connect to the column pinouts of the keypad

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

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

    void loop(){
      char key = keypad.getKey();

      if (key != NO_KEY){
        Serial.println(key);
      }
    }