arduino keypad library

1#include <Keypad.h>
2
3const byte ROWS = 4; 
4const byte COLS = 4; 
5
6char hexaKeys[ROWS][COLS] = {
7  {'1', '2', '3', 'A'},
8  {'4', '5', '6', 'B'},
9  {'7', '8', '9', 'C'},
10  {'*', '0', '#', 'D'}
11};
12
13byte rowPins[ROWS] = {9, 8, 7, 6}; 
14byte colPins[COLS] = {5, 4, 3, 2}; 
15
16Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); 
17
18void setup(){
19  Serial.begin(9600);
20}
21  
22void loop(){
23  char customKey = customKeypad.getKey();
24  
25  if (customKey){
26    Serial.println(customKey);
27  }
28}

1const byte rows = 4; //four rows
2const byte cols = 3; //three columns
3char keys[rows][cols] = {
4  {'1','2','3'},
5  {'4','5','6'},
6  {'7','8','9'},
7  {'#','0','*'}
8};
9byte rowPins[rows] = {5, 4, 3, 2}; //connect to the row pinouts of the keypad
10byte colPins[cols] = {8, 7, 6}; //connect to the column pinouts of the keypad
11Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, rows, cols );
12