每隔1秒顯示一次

 unsigned long time1;

int analog_pin=A1;

int pwmled_pin=6;

int val;

void setup()

{

  Serial.begin(9600);

}

void loop() 

{

 val=analogRead(analog_pin);

 val=map(val,0,1023,0,255);

 if(millis()-time1>1000)

  {

   time1=millis();

   Serial.println(val);

  }

 analogWrite(pwmled_pin,val);

}