Dụng cụ chuẩn bị :

breadboard nhỏ ( breadboard small)

arduino Uno R3

9 đèn LED

Mã code : 

byte ledPin[] = {2,3,4,5,6,7,8,9,10}; 
byte pinCount;
void setup() {
  pinCount = sizeof(ledPin);  
  for (int i=0;i<pinCount;i++) {
    pinMode(ledPin[i],OUTPUT);  
  }
}
void loop() {

  for (int i=0; i < pinCount; i++) {
    digitalWrite(ledPin[i],HIGH); 
    delay(500); 
  }
  
  for (int i = 0;i < pinCount; i += 1) {
    digitalWrite(ledPin[i],LOW); 
    delay(500); 
  }
}

(lắp mạch như bên dưới là ok )

gửi bạn .

Code:

// C++ code
//
/*
  This program blinks pin 13 of the Arduino (the
  built-in LED)
*/

void setup()
{
  pinMode(LED_BUILTIN, OUTPUT);
}

void loop()
{
  // turn the LED on (HIGH is the voltage level)
  digitalWrite(LED_BUILTIN, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  // turn the LED off by making the voltage LOW
  digitalWrite(LED_BUILTIN, LOW);
  delay(1000); // Wait for 1000 millisecond(s)
}