งานในคอม 8

#include "LedControl.h"
#include "Keypad.h"
#define C4  262
#define D4  294
#define E4  330
#define F4  349
#define G4  392
#define A4  440
#define B4  494
#define C5  523
char keys[4][4]={
  {7,8,9,0},
  {4,5,6,0},
  {1,2,3,0},
  {0,0,0,0}};
byte rowPins[] = {7,6,5,4};
byte colPins[] = {3,2,1,0};
Keypad keypad = Keypad(makeKeymap(keys),rowPins,colPins,4,4);
int melody[] = {C4,D4,E4,F4,G4,A4,B4,C5};
int dl = 300;
int buzzerpin = 11;
LedControl lc=LedControl(8,10,9,1);
// Pin 8->DIN, 10->CLK, 9->CS(LOAD), 1 = No.of devices
void setup()
{
  lc.shutdown(0,false); 
  lc.setIntensity(0,5);
  lc.clearDisplay(0);
  pinMode(buzzerpin,OUTPUT);
  digitalWrite(buzzerpin,HIGH);
}
void loop()
{
  char key = keypad.getKey();
  if ((key != NO_KEY) && (key < 9))
  {
    lc.setDigit(0,0,key,false);
    tone(buzzerpin, melody[key-1],dl);
    delay(dl);
    digitalWrite(buzzerpin,HIGH);
  }