I'm having troubles getting Arduino and Processing to talk to eachother. Summary: after a few parameters are met Arduino sends a "happy" message to Processing, Processing then takes a snapshot with a webcam.

Arduino code
Code:

int dirpin = 2;		// pin 3 is direction pin
int steppin = 12;		// pin 12 "starts" motor
int val1 = 0;			 // val1 will store sensor1 value
int val2 = 0;			 // val2 will store sensor2 value
int val3 = 0;			 // val3 will store okbutton value
int val4 = 0;			// stores STARTBUTTON count
int SENSOR1 = 4;		 // input pin for sensor1
int SENSOR2 = 5;		// input pin for sensor2
int OKBUTTON = 6;		// input pin for ok button
int STARTBUTTON = 3;	 // on switch
int LED1 = 9;			 // output pin for led1
int LED2 = 8;			  // output pin for led2
int LED3 = 7;			// output pin for "both" led3
int firstSwitch;	     // variable for first switch case
int i;
void setup() {

Serial.begin(9600);

pinMode(dirpin, OUTPUT);
pinMode(steppin, OUTPUT);
pinMode(LED1, OUTPUT);
pinMode(LED2, OUTPUT);
pinMode(LED3, OUTPUT);
pinMode(SENSOR1, INPUT);
pinMode(SENSOR2, INPUT);
pinMode(OKBUTTON, INPUT);
pinMode(STARTBUTTON, INPUT);
}

void loop() {
  Serial.println("absolute\n");
  delay(100);
  while (val4 == 0) {
    val4 = digitalRead(STARTBUTTON);	// check start button
    int firstSwitch = 1;	 // set "starting" switch case
    Serial.println("Starting Here\n");
    delay(100);
  }

  switch (firstSwitch) {
    case 1:				 // start up procedure
    Serial.println("starting - case 1\n");
    delay(100);
    do {
	  val1 = digitalRead(SENSOR1);
	  val2 = digitalRead(SENSOR2);
	  if (val1 == HIGH) {
	    digitalWrite(LED1, HIGH);
	  } else {
	    digitalWrite(LED1, LOW);
	  }
	  if (val2 == HIGH) {
	    digitalWrite(LED2, HIGH);
	  } else {
	    digitalWrite(LED2, LOW);
	  }
	if ((val1 == HIGH) && (val2 == HIGH)) {
	  digitalWrite(LED3, HIGH);
	  do {
	    val3 = digitalRead(OKBUTTON);
	  } while (val3 == LOW);
	}
	} while ((val1 == LOW) || (val2 == LOW));
	digitalWrite(LED1, LOW);
	digitalWrite(LED2, LOW);
	digitalWrite(LED3, LOW);
	break;
    case 2:		     // bad procedure, add in buzzer
	Serial.println("bad - case 2\n");
	  delay(100);
	do {
	  val1 = digitalRead(SENSOR1);
	  val2 = digitalRead(SENSOR2);
	  if (val1 == HIGH) {
	    digitalWrite(LED1, HIGH);
	  } else {
	    digitalWrite(LED1, LOW);
	  }
	  if (val2 == HIGH) {
	    digitalWrite(LED2, HIGH);
	  } else {
	    digitalWrite(LED2, LOW);
	  }
	if ((val1 == HIGH) && (val2 == HIGH)) {
	  digitalWrite(LED3, HIGH);
	  do {
	    val3 = digitalRead(OKBUTTON);
	  } while (val3 == LOW);
	}
	} while ((val1 == LOW) || (val2 == LOW));
	digitalWrite(LED1, LOW);
	digitalWrite(LED2, LOW);
	digitalWrite(LED3, LOW);
	break;
    case 3:				  // good procedure
	Serial.println("good - case 3\n");
	delay(100);
	break;
  }

  digitalWrite(dirpin, LOW);	// Set the direction.
  delay(100);

  for (i = 0; i<10000; i++) {	 // 10000 microsteps
     digitalWrite(steppin, LOW);	// low to high for rising edge
     digitalWrite(steppin, HIGH);
     delayMicroseconds(200);	 // close to top speed
  }
  Serial.println("motor has moved\n");
  delay(100);
  val1 = digitalRead(SENSOR1);
  val2 = digitalRead(SENSOR2);
  if ((val1 == HIGH) && (val2 == HIGH)) {    // if val1 & val2 are HIGH
    Serial.println("sensors good\n");
    delay(100);
    Serial.print("Take shot\n");	 // send "ok" to serial port
    delay(100);
    firstSwitch = 0;		// set firstSwitch to zero
    do {
	if (Serial.available() > 0) { // if serial is availabe
	  firstSwitch = Serial.read();	// read serial into firstSwitch
	}
    } while (firstSwitch == 0);	// keep checking if processing has finished
    Serial.println(firstSwitch, DEC);
    delay(100);
  } else {
    firstSwitch = 2;	 // if val1 or val2 are low set firstSwitch to bad
    Serial.println("sensors did not line up\n");
    delay(100);
  }
}
 

Processing code
Code:

import processing.serial.*;
import processing.video.*;

Serial arduinoPort;
Capture webcam;
int which = 0;

void setup() {
  size(640,480);
  webcam = new Capture(this,640,480);  
  String[] devices = Capture.list();
  println(devices);
  webcam.settings();
  arduinoPort = new Serial(this, Serial.list()[0], 9600);
}

void draw() {
  while (arduinoPort.available() > 0) {
    String inBuffer = arduinoPort.readStringUntil('\n');
    if (inBuffer != null) {						    
	String myString = new String(inBuffer);
	if (myString.equals("Happy")) {
	  which = 1;
	} else {
	  which = 2;
	}
	println(myString);
	switch (which) {
	  case 1:
	    println("Good");     
	    if (webcam.available() == true) {     
		webcam.read();
		image(webcam ,0,0);
	    }
	    saveFrame("line-####.bmp");
	    arduinoPort.clear();
	    arduinoPort.write(3);
	  case 2:
	    println(myString);
	    arduinoPort.clear();
	    arduinoPort.write(2);
	}
    }
  }
} 

I pretty much have two problems
1. When I serial.println strings it always shows up multiple times in the Processing serial window, like so...

absolute
Starting Here
Starting Here
starting - case 1
starting - case 1
motor has moved
motor has moved
sensors good
sensors good
Happy
Happy
2
2

I think this happens because Processing checks the serial port multiple times before its updated, I'm not really sure how to fix this though.

2. As you can see in the above serial window post, "Happy" is received by Processing, however it doesn't trigger the webcam to take a snapshot like it should. It just returns a "2" back to the Arduino, which should happen if myString != Happy.

I've tried doing handshake methods and serialEvents() however any tutorials I've found seem to be a bit confusing. Any suggestions would be great!

Thanks

Thanks for the reply knutEinar. I suppose you're right about printing twice, I guess I assumed it was never even getting that far into the code and though printing twice was a serial issue.But I guess that was the problem as I removed one of the println and it works fine now.

As for you making it take snapshots. You actually had a camera take snapshots with the Arduino code I submitted? If this is the case, that's quite bizarre because I  haven't been able to with the arduino code. I've been able to accomplish snapshots with a dumbed down Arduino code that simply serial.println("Happy") when a switch is flipped, but never have I with the code I posted. Do you mind sharing your secret? Ha.

Every time I run it the if (myString.equals("Happy")) sends the switch statement to case 2. Even though I'm getting "Happy" through the serial port. Was there anything you did differently at all?

Thanks

Hey knutEinar, this is my new Processing with the break; statements added. However it still isn't quite working correctly. I'm still using the Arduino code I previously posted.

Code:

import processing.serial.*;
import processing.video.*;

Serial arduinoPort;
Capture webcam;
int which = 0;

void setup() {
  size(640,480);
  webcam = new Capture(this,640,480);  
  String[] devices = Capture.list();
  println(devices);
  webcam.settings();
  arduinoPort = new Serial(this, Serial.list()[0], 9600);
}

void draw() {
  while (arduinoPort.available() > 0) {
    String inBuffer = arduinoPort.readStringUntil('\n');
    if (inBuffer != null) {						    
	String myString = new String(inBuffer);   
	if (myString.equals("Happy")) {    
	  which = 1;
	} else {
	  which = 2;
	}
	switch (which) {
	  case 1:
	    println("Good");     
	    if (webcam.available() == true) {     
		webcam.read();
		image(webcam ,0,0);
	    }
	    saveFrame("line-####.bmp");
	    arduinoPort.clear();
	    arduinoPort.write(3);
	    break;
	  case 2:
	    println(myString);
	    arduinoPort.clear();
	    arduinoPort.write(2);
	    break;
	}
    }
  }
} 

Quote:


As a matter of fact I am a bit happy because when it goes to the 'case 2' it does send a '2' back to the Arduino and the Arduino responds to it correctly. Sending a '2' to the Arduino represents anything I'm receiving from the Arduino EXCEPT "Happy." I want a snapshot when Processing receives "Happy."

As you can see from the serial window text below, I am getting "Happy" sent across the serial port. It's just not going to case 1, it always goes to case 2. So for the most part it does work correctly, its just not taking a snapshot whenever "Happy" is sent.

Starting Here
starting - case 1
motor has moved
sensors good
Happy
2

Thanks again for your responses.

Its working!

As soon as I read your suggestion of trim() it hit me that was probably the problem. I was using readStringUntil('\n') and putting line feeds at the end of everything I was sending from the Arduino. Now I can honestly say: I believe everything is working perfectly now. At least working correctly as far as the code goes. Now comes physical integration with the actual motor and sensors.

Thank you again knutEinar, I sincerely appreciate the help. Here's the final Processing code I got it going with. Just had to add in the trim() and modified case 2 a little.

Code:

import processing.serial.*;
import processing.video.*;

Serial arduinoPort;
Capture webcam;
int which = 0;

void setup() {
  size(640,480);
  webcam = new Capture(this,640,480);  
  String[] devices = Capture.list();
  println(devices);
  webcam.settings();
  arduinoPort = new Serial(this, Serial.list()[0], 9600);
}

void draw() {
  while (arduinoPort.available() > 0) {
    String inBuffer = arduinoPort.readStringUntil('\n');
    if (inBuffer != null) {						    
	String myString = new String(inBuffer); 
	String myString2 = trim(myString);
	if (myString2.equals("Happy")) {
	  which = 1;
	} else {
	  which = 2;
	}
	switch (which) {
	  case 1:
	    println("Good");     
	    if (webcam.available() == true) {     
		webcam.read();
		image(webcam ,0,0);
	    }
	    saveFrame("line-####.bmp");
	    arduinoPort.clear();
	    arduinoPort.write(3);
   
	    break;
	  case 2:
	    if (myString2.equals("nope")) {
		arduinoPort.clear();
		arduinoPort.write(2);
	    }
	    println(myString2);
	    break;
	}
    }
  }
}