KeyPad 버튼에 해당하는 LED ON/OFF

• KeyPad 버튼을 누르고 있을 경우 동일한 번호의 LED가 ON
• KeyPad 버튼을 누르지 않을 경우 LED 전체 OFF

< keypad1.c >

#include <wiringPi.h>

const int LedRed[8] = { 4, 17, 18, 27, 22, 23, 24, 25};
const int Keypad[8] = { 16, 13, 12, 6, 21, 26, 20, 19};

// KeyPad 번호 읽어오기
int KeypadRead(){
	int i, keypadnum = -1;
    for(i=0; i<8; i++){
    	// 
    	if(!digitalRead(Keypad[i])){
        	keypadnum = i; 
            break;
        }
    }
    return keypadnum;
}

void LedControl(int keypadnum){
	int i;
    for(i=0; i<8; i++){
    	if(i==keypadnum)
        	digitalWrite(LedRed[i], HIGH);
        else
        	digitalWrite(LedRed[i], LOW);
    }
}

int main(void){
	int i, keypadnum = -1;
    
    if(wiringPiSetupGpio()==-1)
    	return 1;
    
    for(i=0; i<8; i++){
    	pinMode(LedRed[i], OUTPUT);
        digitalWrite(LedRed[i], LOW);
    }
    
    for(i=0; i<8; i++)
    	pinMode(Keypad[i], INPUT);

	while(1){
    	keypadnum = KeypadRead();
        LedControl(keypadnum);
    }
    
    return 0;
}

KeyPad 버튼에 해당하는 LED ON/OFF

• Key 4 선택 시 LED 1~8의 순서로 ON/OFF
• Key 5 선택 시 LED 8~1의 순서로 ON/OFF

< keypad2.c >

#include <wiringPi.h>

// KeyPad 번호 읽어오기
int KeypadRead(){
	int i, keypadnum = -1;
    for(i=0; i<2; i++){
    	// 
    	if(!digitalRead(Keypad[i])){
        	keypadnum = i; 
            break;
        }
    }
    return keypadnum;
}

void LedControl(int keypadnum){
	int i;
    for(i=0; i<8; i++){
    	if(i==keypadnum)
        	digitalWrite(LedRed[i], HIGH);
        else
        	digitalWrite(LedRed[i], LOW);
    }
}

int main(void){

	int i, keypadnum = -1;
    if(wiringPiSetupGpio()==-1)
    	return 1;
    
    for(i=0; i<8; i++){
    	pinMode(LedRed[i], OUTPUT);
        digitalWrite(LedRed[i], LOW);
    }
    
    for(i=0; i<8; i++)
    	pinMode(Keypad[i], INPUT);
    
    while(1){
    	kepadnum = KeypadRead();
        if(keypadnum==0){
        	for(i=0;i<8;i++){
            	LedControl(i);
                delay(500):
            }
            digitalWrite(Led[i-1], LOW); // LED[7] 한번 쉬기
        }
        else if(keypadnum==1){
        	for(i=7;i>=0;i--){
            	LedControl(i);
                delay(500):
            }
            digitalWrite(Led[i+1], LOW); // LED[1] 한번 쉬기
        }
    }
    return 0;
}

< keypad3.c >

• KeyPad 버튼을 눌렀다 뗄 경우 동일한 번호의 LED ON/OFF
• LED가 ON 상태이면 OFF로 전환 / LED가 OFF 상태이면 ON으로 전환
• Debouncing 현상 처리

#include <wiringPi.h>

const int LedRed[8] = { 4, 17, 18, 27, 22, 23, 24, 25};
const int Keypad[8] = { 16, 13, 12, 6, 21, 26, 20, 19};

// Debouncing
int debounceDelay = 50; 
unsigned long lastDebounceTime[8] = {0, 0, 0, 0, 0, 0, 0, 0};
int buttonstate[8] = {1, 1, 1, 1, 1, 1, 1, 1};
int lastButtonState[8]= {1, 1, 1, 1, 1, 1, 1, 1};

// KeyPad 번호 읽어오기
int KeypadRead(){
	int i, reading, keypadnum = -1;
    
    for(i=0; i<8; i++){
        reading = digitalRead(Keypad[i]); 
    	
        // Button의 변화가 있으면 변화 시간을 저장
        if (reading != lastButtonState[i])
        	lastDebounceTime[i] = millis();
        
       	// DebounceDelay이상일 때만 실행
        if ((millis() - lastDebounceTime) > debounceDelay){
             if(!digitalRead(Keypad[i])){
             keypadnum = i; 
             lastButtonState[i] = reading;
             break;
             }
         }
    }
    return keypadnum;
}

void LedControl(int keypadnum){
	int i;
    for(i=0; i<8; i++){
    	if(i==keypadnum)
        	digitalWrite(LedRed[i], HIGH);
        else
        	digitalWrite(LedRed[i], LOW);
    }
}

int main(void){
	int i, keypadnum = -1;
    
    if(wiringPiSetupGpio()==-1)
    	return 1;
    
    for(i=0; i<8; i++){
    	pinMode(LedRed[i], OUTPUT);
        digitalWrite(LedRed[i], LOW);
    }
    
    for(i=0; i<8; i++)
    	pinMode(Keypad[i], INPUT);

	while(1){
    	keypadnum = KeypadRead();
        LedControl(keypadnum);
    }
    
    return 0;
}