用內建電阻控制LED

 int sw=10;

int led=2;

int value=0;

void setup() {

  // put your setup code here, to run once:

 pinMode(sw,INPUT_PULLUP);

 pinMode(led,OUTPUT);

}

void loop() {

  // put your main code here, to run repeatedly:

value=digitalRead(sw);

if(value==1)

{

  digitalWrite(led,LOW);delay(200);

}

else

{

  digitalWrite(led,HIGH);

}

}