Arduino hands-on workshop

Giorno 2 – Interfacciamento con PC: Arduino + Processing

Roberto Gallea – roberto.gallea@unipa.it

Comunicazione seriale

• Arduino può utilizzare la connessione seriale (USB) non solo per l’alimentazione…

• …Ma anche per comunicare con il computer host

– Scambio dati

– Debug

Monitor seriale

Comunicazione seriale

• Non solo Monitor Seriale

• Comunicazione Seriale

• Scambio di dati con altre applicazioni

• rocessing

Esempio «a tumpulata»

const int ledPin = 9; // the pin that the LED is

attached to

void setup()

{

// initialize the serial communication:

Serial.begin(9600);

// initialize the ledPin as an output:

pinMode(ledPin, OUTPUT);

}

void loop() {

byte brightness;

// check if data has been sent from the computer:

if (Serial.available()) {

// read the most recent

brightness = Serial.read();

// set the brightness of the LED:

analogWrite(ledPin, brightness);

}

}

import processing.serial.*;

Serial port;

void setup() {

size(256, 150);

println("Available serial ports:");

println(Serial.list());

port = new Serial(this, Serial.list()[0], 9600);

//port = new Serial(this, "COM1", 9600);

}

void draw() {

// draw a gradient from black to white

for (int i = 0; i < 256; i++) {

stroke(i);

line(i, 0, i, 150);

}

// write the current X-position of the mouse to the serial port

// as a single byte

port.write(mouseX);

}

Esempio «a tumpulata»

Cos’è Processing

• Nasce come software per artisti e visual designers

• Linguaggio di programmazione specifico per generare e modificare immagini

• Diventato uno strumento ad uso generico

Info iniziali

• Aspetta… Ma sembra Arduino?!

• Il sw di Arduino deriva da esso, infatti sono molto simili

• Arduino -> setup(), loop()

• Processing -> setup(), draw()

(mini) Tutorial Processing

void setup() {

size(480, 120);

}

void draw() {

if (mousePressed) {

fill(0);

} else {

fill(255);

}

ellipse(mouseX, mouseY, 80, 80);

}

(mini) Tutorial Processing

color c = color(0);

float x = 0;

float y = 100;

float speed = 1;

void setup() {

size(200,200);

}

void draw() {

background(255);

move();

display();

}

void move() {

x = x + speed;

if (x > width) {

x = 0;

}

}

void display() {

fill(c);

rect(x,y,30,10);

}

Definisce la dimensione della finestra

Imposta il colore di sfondo

Aggiorna la posizione dell’oggetto

Disegna l’oggetto

(mini) Tutorial Processing

int[] xvals; int[] yvals; int[] bvals; void setup() { size(640, 360); noSmooth(); xvals = new int[width]; yvals = new int[width]; bvals = new int[width]; } int arrayindex = 0; void draw() { background(102); for(int i = 1; i < width; i++) { xvals[i-1] = xvals[i]; yvals[i-1] = yvals[i]; bvals[i-1] = bvals[i]; }

// Add the new values to the end of the array xvals[width-1] = mouseX; yvals[width-1] = mouseY; if(mousePressed) { bvals[width-1] = 0; } else { bvals[width-1] = 255; } fill(255); noStroke(); rect(0, height/3, width, height/3+1); for(int i=1; i<width; i++) { stroke(255); point(i, xvals[i]/3); stroke(0); point(i, height/3+yvals[i]/3); stroke(255); line(i, 2*height/3+bvals[i]/3, i, (2*height/3+bvals[i-1]/3)); } }

(mini) Tutorial Processing

int[] xvals; int[] yvals; int[] bvals; void setup() { size(640, 360); noSmooth(); xvals = new int[width]; yvals = new int[width]; bvals = new int[width]; } int arrayindex = 0; void draw() { background(102); for(int i = 1; i < width; i++) { xvals[i-1] = xvals[i]; yvals[i-1] = yvals[i]; bvals[i-1] = bvals[i]; }

// Add the new values to the end of the array xvals[width-1] = mouseX; yvals[width-1] = mouseY; if(mousePressed) { bvals[width-1] = 0; } else { bvals[width-1] = 255; } fill(255); noStroke(); rect(0, height/3, width, height/3+1); for(int i=1; i<width; i++) { stroke(255); point(i, xvals[i]/3); stroke(0); point(i, height/3+yvals[i]/3); stroke(255); line(i, 2*height/3+bvals[i]/3, i, (2*height/3+bvals[i-1]/3)); } }

Arduino + Processing: #1

Arduino + Processing: #1

int input = A0;

int val = 0;

void setup() {

Serial.begin(9600);

}

void loop() {

val = analogRead(input);

Serial.write(val/4);

delay(10);

}

import processing.serial.*;

int value = 0;

Serial port;

void setup() {

port = new Serial(this,Serial.list()[0],9600);

// change to correct com port(1)

size(600,600); // size of the window

background(200); // color of the backround

}

void draw() {

while ((value = port.read()) != -1) {

println(value);

fill(value);

rect(0,0,600,600);

}

}

Arduino + Processing: #2

void setup() {

// initialize the serial communication:

Serial.begin(9600);

}

void loop() {

// send the value of analog input 0:

Serial.println(analogRead(A0));

// wait a bit for the analog-to-digital converter

// to stabilize after the last reading:

delay(2);

}

import processing.serial.*;

Serial myPort; // The serial port

int xPos = 1; // horizontal position of the graph

void setup () {

// set the window size:

size(400, 300);

// List all the available serial ports

println(Serial.list());

// I know that the first port in the serial list on my mac

// is always my Arduino, so I open Serial.list()[0].

// Open whatever port is the one you're using.

myPort = new Serial(this, Serial.list()[0], 9600);

// don't generate a serialEvent() unless you get a newline

myPort.bufferUntil('\n');

// set inital background:

background(0);

}

void draw () {

// everything happens in the serialEvent()

}

Arduino + Processing: #2

void setup() {

// initialize the serial communication:

Serial.begin(9600);

}

void loop() {

// send the value of analog input 0:

Serial.println(analogRead(A0));

// wait a bit for the analog-to-digital converter

// to stabilize after the last reading:

delay(2);

}

import processing.serial.*;

Serial myPort; // The serial port

int xPos = 1; // horizontal position of the graph

void setup () {

// set the window size:

size(400, 300);

// List all the available serial ports

println(Serial.list());

// I know that the first port in the serial list on my mac

// is always my Arduino, so I open Serial.list()[0].

// Open whatever port is the one you're using.

myPort = new Serial(this, Serial.list()[0], 9600);

// don't generate a serialEvent() unless you get a newline

myPort.bufferUntil('\n');

// set inital background:

background(0);

}

void draw () {

// everything happens in the serialEvent()

}

void serialEvent (Serial myPort) {

// get the ASCII string:

String inString = myPort.readStringUntil('\n');

if (inString != null) {

// trim off any whitespace:

inString = trim(inString);

// convert to an int and map to the screen height:

float inByte = float(inString);

inByte = map(inByte, 0, 1023, 0, height);

// draw the line:

stroke(127,34,255);

line(xPos, height, xPos, height - inByte);

// at the edge of the screen, go back to the beginning:

if (xPos >= width) {

xPos = 0;

background(0);

}

else {

// increment the horizontal position:

xPos++;

}

}

}

Lampada RGB - Connessioni

Lampada RGB - Arduino

int Red = 3; //

int Green = 5; //pin definitions

int Blue = 6; //

int r = 125; //

int g = 125; //default all the pins to 125(white)

int b = 125; //

void setup()

{

Serial.begin(9600);

pinMode(Red,OUTPUT);

pinMode(Green,OUTPUT); // set the pin modes

pinMode(Blue,OUTPUT);

}

void loop()

{

if(Serial.available()==9) // while there is data

{

r= (Serial.read()-48)*100; // read the first byte

r=r + (Serial.read()-48)*10; // read the second

byte......

r=r + Serial.read()-48; // so on so forth

g= (Serial.read()-48)*100;

g=g+ (Serial.read()-48)*10;

g=g + Serial.read()-48;

b= (Serial.read()-48)*100 ;

b=b+ (Serial.read()-48)*10;

b=b + Serial.read()-48;

int d = Serial.read();// this is just to clear the end line

character

}

analogWrite(Red,r); //

analogWrite(Green,g);

analogWrite(Blue,b);

}

Lampada RGB - Processing

• Codice troppo lungo, su file.

Grazie!

BONUS: FIRMATA LIBRARY

Firmata

• Protocollo di comunicazione fra microcontrollori e computer

• Permette di controllare gli input/output del µcontrollore tramite porta seriale…

• …cioè non è necessario leggere e scrivere messaggi, la libreria lo fa per noi

Test Firmata

• Aprire e caricare lo sketch File->Esempi->Firmata->OldStandardFirmata

• Avviare firmata_test.exe

Lampada RGB con Firmata

• Stesso circuito

• Sketch StandardFirmata su Arduino

Lampada RGB con Firmata

• Stesso circuito

• Sketch StandardFirmata su Arduino

Lampada RGB con Firmata

• Stesso circuito

• Sketch StandardFirmata su Arduino

import processing.serial.*; import cc.arduino.*; Arduino arduino; int red; int green; int blue; void setup() { size(512, 200); arduino = new Arduino(this, Arduino.list()[0], 115200); } void draw() { red = constrain(mouseX/2, 0, 255); green = constrain(255 - mouseY, 0, 255); blue = constrain(255 - mouseX/2, 0, 255); background(red, green, blue); arduino.analogWrite(3, red); arduino.analogWrite(5, green); arduino.analogWrite(6, blue); }