# 20220929 arduino

## 練習1

void setup() {
  size(400, 400);
}

void draw() {
  line(mouseX, mouseY, width/2, height/2);
  strokeWeight(millis()/1000);
}
void mouseClicked() {
  println("mouseClick");
  saveFrame("image###.jpg");
  background(random(255));
  stroke(random(255), random(255), random(255));
}

## 練習1圖片

---

## Arduino Serial

void setup() {
  Serial.begin(9600);
}

void loop() {
  Serial.println(1);
  delay(1000);
  Serial.println(2);
  delay(1000);
}

### processing code: arduino 1,2 => processing =>background

import processing.serial.*;
Serial myPort;
int val;
void setup()
{
  size(500, 500);
  myPort = new Serial(this, "COM4", 9600);
}

void draw()
{
  if ( myPort.available() > 0) {  // If data is available,
    val = myPort.read();         // read it and store it in val
    println(val+":"+char(val));
    if (val == 49) background(255, 0, 0, 0);
    if (val == 50) background(0, 255, 0);
  }
}

### 練習 循序圖

@startuml

user -> button: 按下按鈕
button -> arduino: 改變電路的high gnd
arduino -> serial: 1,2
serial -> processing: 1,2
processing -> display: ellipse2rect

@enduml

### arduino button -> 1,2

void setup() {
  Serial.begin(9600);
  pinMode(2, INPUT_PULLUP);
}

void loop() {
  delay(300);
  if (digitalRead(2) == HIGH) {
    Serial.println(1);
  }

  if (digitalRead(2) == LOW) {
    Serial.println(2);
  }
}