# 20220922 code arduino

## arduino button -> 0 -> led blink

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(2, INPUT);
  Serial.begin(9600);
  Serial.println("begin");
}
void loop() {
    Serial.println(digitalRead(2));
  if (digitalRead(2) == 0) {
    digitalWrite(LED_BUILTIN, HIGH);
    delay(100);  // ms 1000 => 1s
    digitalWrite(LED_BUILTIN, LOW);
    delay(100);  // ms 1000 => 1s
  }
  delay(30);
}

## arduino led code

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


void loop() {
  digitalWrite(LED_BUILTIN, HIGH);   
  delay(1000);   // ms 1000 => 1s
  digitalWrite(LED_BUILTIN, LOW);   
  delay(1000);   // ms 1000 => 1s
  

}

## 亂數點線面

void setup() {  // once
  size(300, 400);
  background(random(255), random(255), 100);
  background(255);
}

void draw() {  //  loop
  point(random(width), random(height));
  line(width/2, height/2, random(width), random(height));
  rect(random(width), random(height), 30, 20);
  ellipse(random(width), random(height), 30, 20);
  fill(random(255),255,random(255),55);
}

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阿達