Here are two from a few of them I have worked around but fail. (1), (2) I see the 2nd example from a site that seems like a legit Github of Processing team (?) is a very updated one but I still get only 0 from it. However, when run the python in terminal my sensors do work well.

I'm using Rpi 3 B and my code is exactly copy and paste from the 2nd. I've created a new folder in Rpi and have two file.pde one is a class and one is a main function (setup and draw).

So, what else should I do or any info that I should looking into to fix this problem?

Any idea ? Thanks !

import processing.serial.*; 

Serial mySerialPort;          
Serial myBluePort;
PFont myFont;          
String serialString;       
String blueString;
int lf = 10;            // ASCII linefeed aka '/n'

void setup() { 

  frameRate(1000);
  size(400,200); 
  myFont = loadFont("ArialMT-18.vlw");  // Processing>Tools>Create Font 
  textFont(myFont, 18); 
  printArray(Serial.list());  

  mySerialPort = new Serial(this, Serial.list()[1], 115200); 
  mySerialPort.bufferUntil(lf); 

  myBluePort = new Serial(this, Serial.list()[0], 1200); 
  //myBluePort = new Serial(this, Serial.list()[0], 2400); 
  //myBluePort = new Serial(this, Serial.list()[0], 4800); 
  //myBluePort = new Serial(this, Serial.list()[0], 9600); 
  //myBluePort = new Serial(this, Serial.list()[0], 14400);
  //myBluePort = new Serial(this, Serial.list()[0], 19200); 
  //myBluePort = new Serial(this, Serial.list()[0], 28800); 
  //myBluePort = new Serial(this, Serial.list()[0], 38400); 
  //myBluePort = new Serial(this, Serial.list()[0], 57600); 
  //myBluePort = new Serial(this, Serial.list()[0], 76800); 
  //myBluePort = new Serial(this, Serial.list()[0], 115200); 
  //myBluePort = new Serial(this, Serial.list()[0], 230400); 
  //myBluePort = new Serial(this, Serial.list()[0], 250000); 
  //myBluePort = new Serial(this, Serial.list()[0], 460800); 
  //myBluePort = new Serial(this, Serial.list()[0], 921600); 
  //myBluePort = new Serial(this, Serial.list()[0], 1000000); 
   myBluePort.bufferUntil(lf);
} 

void draw() { 

  if ( mySerialPort.available() > 0) serialString = mySerialPort.readString();
  if ( myBluePort.available() > 0) blueString = myBluePort.readString();

  background(0); 
  text("Receiving serial data : " + trim(serialString), 10,20); 
  text("Receiving bluetooth data : " + trim(blueString), 10,40); 

} 

I have a couple servos hooked up to an Adafruit 16-Channel PWM/Servo HAT on a Raspberry Pi 3 that I would like to control via Processing. Adafruit provides a python library that allows easy control of the connected servos via python commands like "setPWM(self, channel, on, off)". I can control the servos fine from the command line or python script, but have no clue how to execute these inside Processing. Any help would be much appreciated!

I have a Adafruit 4x3 matrix telephone keypad, which is already connected to an arduino mega and working. On top of that I have soldered an MP3 shield. When the years 1980 until 2016 are pressed, a certain audio file is played. This is all working. Now I want to implement different other audios, for example when you press the star or hash key. Or a constant dial tone in the background, which stops when a certain year is being pressed.

Can anyone help me with that?

Thanks!

However, it seems I met the error message as titled frequently... Error, disabling serialEvent() for /dev/ttyUSB0 null

Any suggestions?

I have bought a bunch of APA102C led strips (what adafruit brands as dotstar) and I am looking to control it with processing running on a raspberry pi.

I have been looking into how to make this work (basically using my strips as a screen) and it seems to me the best would be to use the current adafruit which is written in C. Is there a way for me to use this with processing?

This is potentially a silly question but I am thankful for your help,

Thanks in advance.

the code is a combination of the following codes:
1) https://processing.org/tutorials/electronics/ (Example 5A and 5B)
2) https://learn.adafruit.com/adafruit-motor-shield-v2-for-arduino/using-dc-motors
3) http://www.sojamo.de/libraries/controlP5/examples/controllers/ControlP5knob/ControlP5knob.pde

Processing:
// Write data to the serial port according to the status of a ControlP5 Knob controlled
// by the mouse. uses values from 0-255.

import processing.serial.*;
import controlP5.*; // import library for knob

Serial port;        // Create serial port object 
ControlP5 cp5;      // defines the type "cp5" as a variable "type" defined in ControlP5  for knob

int myColorBackground = color(0,0,0);  
int knobValue = 100;  

Knob myKnobA;  
Knob myKnobB;  

void setup() {

  port = new Serial(this, 9600); 
  size(700,400);  
  smooth();  
  noStroke(); 

  cp5 = new ControlP5(this);  //object created from library (what is this exactly?)  

  myKnobA = cp5.addKnob("knob")  // "method" is add(ControllerInterface<?> theElement) 
               .setRange(0,255) 
               .setValue(50)  
               .setPosition(100,70)  
               .setRadius(50)  // for knob
               .setDragDirection(Knob.VERTICAL)  
               ;                  
} 

void draw() {   

  background(myColorBackground); 
  fill(knobValue);   
  rect(0,height/2,width,height/2);   
  fill(0,100);   
  rect(80,40,140,320);  
} 

void knob(int theValue) {   
  myColorBackground = color(theValue);  
  println("a knob event. setting background to "+theValue); 
  port.write(theValue); 
}  

Arduino: // Read data from the serial and turn a DC motor on or off according to the value. with adafruit motor driver // board code included

#include <Wire.h>     
#include <Adafruit_MotorShield.h> 
#include "utility/Adafruit_PWMServoDriver.h"  

// Create the motor shield object with the default I2C address   
// Adafruit_MotorShield AFMS = Adafruit_MotorShield(); 
// DONT USE THIS ONE IF RUNNING MULIPLE MOTORS   
// Or, create it with a different I2C address (say for stacking)   
Adafruit_MotorShield AFMS = Adafruit_MotorShield(0X60);  // 1st board if stacking 

// Select which 'port' M1, M2, M3 or M4. In this case, M1
Adafruit_DCMotor *myMotor1 = AFMS.getMotor(1); // 1st board, M1 

char val;             // Data received from the serial port

void setup() { 
  Serial.begin(9600);                  // Start serial communication at 9600 bps 

  AFMS.begin();  // create with the default frequency 1.6KHz, this connects to the 
             // controller- need one for each motor? nope.  
} 

void loop() { 
  if (Serial.available()) {            // If data is available,  
    val = Serial.read();               // read it and store it in val 
  } 
  myMotor1->setSpeed(val); 
  myMotor1->run(FORWARD); 
  delay(100);                          // Wait 100 milliseconds for next reading
}

Anyone know how i can do this?

Thanks

Processing code

   import processing.serial.*;
   Serial port;
   int c;

   void setup() {
     size(300, 150);
    // println("Available serial ports:");
    // println(Serial.list());
    port = new Serial(this, "/dev/cu.usbmodem1421", 9600);
    c = 2;
   }

  void draw() {
  background(255);
  line(100, 0, 100, height);
  line(200, 0, 200, height);
   // write the current X-position of the mouse to the serial port as
  // a single byte

 int newc = int(1 + mouseX/100);
 if (newc != c) {
 c = newc; 

println(">> " + c); // DEBUG
port.write("" + c);
 }
}

Arduino code

   #include <Adafruit_GFX.h>    // Core graphics library
   #include <Adafruit_ST7735.h> // Hardware-specific library
   #include <SPI.h>

   #define TFT_CS     10
   #define TFT_RST    9
   #define TFT_DC     8
   #define TFT_SCLK 13
   #define TFT_MOSI 11

   Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_MOSI, TFT_SCLK, TFT_RST);

   void setup(void) {
     Serial.begin(9600);
     tft.initR(INITR_144GREENTAB);   
     tft.fillScreen(ST7735_BLACK);
     Serial.println("OK!");
   }

   void loop() {
     tft.invertDisplay(false);
     if (Serial.available()) {
       byte c = Serial.read();
       if (c == '1') {
         testdrawrects(ST7735_GREEN);
       } else if (c == '2') {
         testdrawrects(ST7735_WHITE);      
       } else if (c == '3') {
         testdrawrects(ST7735_RED);
       }
       Serial.println(c); // DEBUG
     }
   }

   void testdrawrects(uint16_t color) {
     // tft.fillScreen(ST7735_BLACK);
     for (int16_t x=0; x < tft.width(); x+=6) {
       tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color);
     }
   }

Processing Code

import processing.serial.*;
import controlP5.*;

Serial myPort;
ControlP5 cp5;
DropdownList serialPortsList;
Serial serialPort;
final int BAUD_RATE=9600;
ControlTimer c;
Textlabel t;
Textlabel txtlblwhichcom;
Textarea commTextarea;
ListBox commListbox;
Serial[] myPorts=new Serial[1];

int col=color(255);
int segment=4;
String val[];
long current;
long previous;
long timePassed;
String timeMillis;
PrintWriter output;
String photo;
String [] var=new String[4];
String vel;
String time="0";
int timeMeasure;
String dir;
String onOff="0";
int onOffMeasure;
String fileName;
String fileN;
String textValue="";
boolean firstContact=false;
RadioButton rb;

void setup(){
  myPort=new Serial(this, Serial.list()[3], 9600);
  myPort.bufferUntil('\n');
  size(700,500);
  PFont font=createFont("arial", 20);
  String[] portNames=Serial.list();
  cp5=new ControlP5(this);
  serialPortsList=cp5.addDropdownList("Serial ports").setPosition(10,10).setWidth(200);
  for(int i=0;i<portNames.length;i++) serialPortsList.addItem(portNames[i],i);

  c=new ControlTimer();
  t=new Textlabel(cp5,"--",100,100);
  c.setSpeedOfTime(1);

  cp5.addCheckBox("checkBox")
    .setPosition(250, 330)
    //.setColorBackground(color(255,13,227))
    .setColorForeground(color(120))
    .setColorActive(color(255))
    .setColorLabel(color(255))
    .setSize(40, 40)
    .setItemsPerRow(3)
    .setSpacingColumn(100)
    .setSpacingRow(20)
    .addItem("Photogate 1", 0)
    .addItem("Photogate 2", 50);

  cp5.addTextfield("Belt Velocity (mm/s)")
     .setPosition(20,90)
     .setSize(200,40)
     .setFont(font)
     .setFocus(true)
     .setColor(color(255,0,0))
     ;

  cp5.addTextfield("Run Time (s)")
     .setPosition(20,160)
     .setSize(200,40)
     .setFont(font)
     .setFocus(false)
     .setColor(color(255,0,0))
     ;

  cp5.addTextfield("Text File Name")
     .setPosition(20,230)
     .setSize(200,40)
     .setFont(font)
     .setFocus(false)
     .setColor(color(255,0,0))
     ;           

  cp5.addButton("Enter")
     .setValue(0)
     .setPosition(240,90)
     .setSize(80,40)
     .getCaptionLabel().align(ControlP5.CENTER, ControlP5.CENTER)
     ;

 cp5.addButton("ENTER")
     .setValue(0)
     .setPosition(240,160)
     .setSize(80,40)
     .getCaptionLabel().align(ControlP5.CENTER, ControlP5.CENTER)
     ;

 cp5.addButton("EnteR")
     .setValue(0)
     .setPosition(240,230)
     .setSize(80,40)
     .getCaptionLabel().align(ControlP5.CENTER, ControlP5.CENTER)
     ;    

  cp5.addButton("Start")
     .setValue(0)
     .setPosition(120,410)
     .setSize(80,40)
     .setColorBackground(color(9,158,12))
     .setColorLabel(color(0,0,0))
     .getCaptionLabel().align(ControlP5.CENTER, ControlP5.CENTER)
     ;

  cp5.addButton("Stop")
     .setValue(0)
     .setPosition(480,410)
     .setSize(80,40)
     .setColorBackground(color(168,8,8))
     .setColorLabel(color(0,0,0))
     .getCaptionLabel().align(ControlP5.CENTER, ControlP5.CENTER)
     ;

  rb = cp5.addRadioButton("radioButton")
         .setPosition(480,100)
         .setSize(90,40)
         .setColorForeground(color(120))
         .setColorActive(color(255))
         .setColorLabel(color(255))
         .setItemsPerRow(1)
         .setSpacingColumn(50)
         .addItem("Clockwise",1)
         .addItem("Counter-ClockWise",2)
         ;
  textFont(font);
}

void draw(){
  current=millis();
  background(0);
  fill(255);
  t.setValue(c.toString());
  t.draw(this);
  t.setPosition(480,50);

  if(segment==0){
    var[0]=vel;
    var[1]=time;
    var[2]=dir;
    var[3]=onOff;
    timeMeasure=Integer.parseInt(time);
    onOffMeasure=Integer.parseInt(time);
    println("segment 1 end");
    segment=1;
  }
  else if(segment==1){
    for(int x=0;x<4;x++){
      myPort.write(var[x]);
      print("sent ");
      println(var[x]);
    }

    segment=2;
    previous=current;
    output=createWriter(fileName);
    println("wrote file");
  }
  else if(segment==2){
    if(myPort.available()>0){
      photo=myPort.readStringUntil('\n');
      output.print(photo);
      timePassed=current-previous;
      timeMillis=str(timePassed);
      output.println(timeMillis);
    }

    if((current-previous)>=(timeMeasure*1000)){
      segment=3;
      onOff="0";
      println("segment 2 finished");
    }
  }
  else if(segment==3){
    var[0]="0";
    var[1]="0";
    var[2]="0";
    var[3]=onOff;

    for(int x=0;x<4;x++){
      myPort.write(var[x]);
    }

    output.flush();
    output.close();

    segment=4;
    println("segment 3 finished");
  }
  else{
    segment=4;
    //println("fish");
  }
}

public void Enter(){
  vel=cp5.get(Textfield.class,"Belt Velocity (mm/s)").getText();
  println("Got Velocity");
}

public void ENTER(){
  time=cp5.get(Textfield.class,"Run Time (s)").getText();
  println("Got Time");
}

public void EnteR(){
  fileN=cp5.get(Textfield.class,"Text File Name").getText();
  fileName=fileN+".txt";
  println("Got filename");
}

void radioButton(int a) {
  dir=str(a);
  println("a radio Button event: "+a);
}

public void Start(){
  /*if(mousePressed){
    segment=0;
    println("Mouse Working");
  }*/
  if(current>100){
    println("if statement Working");
    segment=0;
    onOff="1";
  }
}

public void Stop(){
  if(current>100){
    segment=3;
    onOff="0";
 }


}

void controlEvent(ControlEvent theEvent){
  if(theEvent.isGroup()){
    if(serialPort !=null){
      serialPort.stop();
      serialPort=null;
    }

    String portName=serialPortsList.getItem((int)theEvent.getValue()).getName();
    try{
      serialPort=new Serial(this,portName,BAUD_RATE);
    }
    catch(Exception e){
    }
  }
}

Arduino Code

#include <Wire.h>
#include <stdlib.h>
#include <Adafruit_MotorShield.h>
#include "utility/Adafruit_PWMServoDriver.h"

Adafruit_MotorShield AFMS=Adafruit_MotorShield();

Adafruit_DCMotor *myMotor=AFMS.getMotor(3);

unsigned long Timems=0;
unsigned long Timeus=0;
int Photogate1=HIGH;
int Photogate2=HIGH;
int PhotogatePin1=10;
int PhotogatePin2=12;
int motorPin=3;
float onOff=0;
float var[4];
int index=0;
float volt;
float direct;
long previous;
float vel;
float time;

void setup(){
  Serial.begin(9600);
  AFMS.begin();
  pinMode(motorPin, OUTPUT);
}

void loop(){
  unsigned long current=millis();

  if(onOff==0){
     if (Serial.available()){
       float incomingValue=Serial.parseFloat();
       var[index]=incomingValue;
       index++;
     }

     if(var[3]==1){
       onOff=var[3];
       previous=current;
     }
  }
  else if(onOff==1){
    vel=var[0];
    time=var[1]*1000;
    direct=var[2];
    volt=vel;
    index=0;

    if(direct==1){
      myMotor->run(FORWARD);
    }
    if(direct==2){
      myMotor->run(BACKWARD);
    }

    onOff=2;
  }
  else if(onOff==2){
    myMotor->setSpeed(volt);

  /*  Photogate1=digitalRead(PhotogatePin1);
    Photogate2=digitalRead(PhotogatePin2);

    if(Photogate1==LOW){
      Timems=millis();
      Timeus=micros();

      Serial.println("Photogate 1");

      delay(100);
    }
    else if(Photogate2==LOW){
      Timems=millis();
      Timeus=micros();

      Serial.println("Photogate 2");

      delay(100);
    }
    else{
      digitalWrite(Photogate1, HIGH);
      digitalWrite(Photogate2, HIGH);
    }
  }   */
    if(Serial.available()){
      float incomingValue=Serial.parseFloat();
      var[index]=incomingValue;
      index++;
    }

    if(var[3]==0){
      onOff=3;
    }
  }
  else{
    vel=var[0];
    time=var[1]*1000;
    direct=var[2];
    onOff=var[3];
    volt=vel;
    index=0;
  }
}