start.ino

#define DIR_MOTOR_PEN 9
#define STEP_MOTOR_PEN 10
#define DIR_MOTOR_PLATE 11
#define STEP_MOTOR_PLATE 12
#define STEP_DURATION 1 //in ms
#define MOTOR_PLATE 2
#define MOTOR_PEN 1

#include <Servo.h> 
 
Servo servo_test; 
Servo myservo;
                
int angle = 0;   
int down = 0; 
int xPin = A1;
int yPin = A0;
int bPin = A5;

int xDir = 0;
int yDir = 0;
int bValue = 0;
int sValue = 0;

int xPosition = 0;
int yPosition = 0;
int xValue = 0;
int yValue = 0;
int pos = 0;

void joystick_position();

void setup() {
  /*-------------------------------------------------------------
  * Serial.begin sets the data rate in bits per second (baud) 
  * for serial data transmission.115200 is the fastest.
  -------------------------------------------------------------*/
  Serial.begin(115200); 
  
  //setting up the pins
  pinMode(xPin, INPUT);
  pinMode(yPin, INPUT);
  pinMode(bPin, INPUT);
  pinMode(DIR_MOTOR_PEN,OUTPUT);
  pinMode(STEP_MOTOR_PEN,OUTPUT);
  pinMode(DIR_MOTOR_PLATE,OUTPUT);
  pinMode(STEP_MOTOR_PLATE,OUTPUT);
 
  //attaching the servo
  myservo.attach(6);
 
  Serial.println("Program started!");
}

void loop() {
  joystick_position();
}
  
void joystick_position(){
  /* ---------------------------------------------------------------
  * Depending on the joystick position the pen is being moved. 
  * Also, you can change the degree of the pen via a pottentiometer
  * and the servo_move_up and servo_move_down functions
  ----------------------------------------------------------------*/
  
  //x - left or right // y - forward or backward //b - diagonal
  xValue= analogRead(xPin);
  yValue = analogRead(yPin);
  bValue = analogRead(bPin);
  Serial.print(bValue);

  //change the pottentiometer of the arduino and it changes the angle of the pen 
  sValue = map(bValue,0,1023,85,10);
  
  myservo.write(sValue);
 /*-------------------------------------------------------
 * In the following if-else constructions,
 * the constants are cordinates.
 * The max is 1023 to both x and y values. 
 * The middle is with cordinates (512;512).
 * If we use it, the joystick will be too precise
 * and the error percentage will up.
 * That's why we use 525 as middle.
 * When yDir and xDir are 1,we move the pen diagonally
 -------------------------------------------------------*/
 
  if((xValue>490 && xValue <525 ) && (yValue>490 && yValue<525))
  {
    stepStop();        
  } 
  else if((xValue>490 && xValue <525 ))
  {
           if(yValue > 525)
           {     
               //push the y value => pen moves to the right
               yValue = map(yValue,525,1023,20,1);
               yDir = 1;
           } 
           else 
           {
               //push the y value =>  pen to the left 
               yValue = map(yValue,490,0,20,1);
               yDir = 0;
           }
      
      digitalWrite(STEP_MOTOR_PLATE, LOW); 
      stepMeHigh(STEP_MOTOR_PEN,yDir,yValue);

  } 
  else if((yValue>490 && yValue <525 ))
  {     
      if(xValue > 525)
      {      
        //push the y value and it moves the plate forward => the pen moves backward
        xValue = map(xValue,525,1023,20,1);
        xDir = 1;
      } 
      else
      {
        xValue = map(xValue,490,0,20,1);
        xDir = 0;
      }

      digitalWrite(STEP_MOTOR_PEN, LOW);
      stepMeHigh(STEP_MOTOR_PLATE,xDir,xValue);
      
  }
  else
  {
    /*------------------------------------------------
    * By changing the y value( by moving the joystick),
    * we move the position of the plate backward
    *        ===> the pen moves forward.
    ------------------------------------------------*/
    
      if(xValue > 525) //525 - not pushed joystick
      {      
        xValue = map(xValue,525,1023,20,1);
        xDir = 1;
      } 
      else
      {
        xValue = map(xValue,490,0,20,1);
        xDir = 0;
      }
   
      if(yValue > 525)   //525 - not pushed joystick
      {    
        yValue = map(yValue,525,1023,20,1);
        yDir = 1;
      }
      else
      {
        yValue = map(yValue,490,0,20,1);
        yDir = 0;
      }
      
      stepMeHigh(STEP_MOTOR_PLATE,xDir,xValue);
      stepMeHigh(STEP_MOTOR_PEN,yDir,yValue);   
    }
 }

void servo_move_down(){
  
  /*----------------------------------------
  * Via the servo and the pottentiometer,
  * we move the pen downward
  ----------------------------------------*/
    
  for (pos = 90; pos >= 0; pos -= 1) //change the angle of the pen from 90 to 0
  { 
    myservo.write(pos);              //command to rotate the servo to the specified angle      
  }
 
}

void servo_move_up(){
 
  /*----------------------------------------
  * Via the servo and the pottentiometer,
  * we move the pen upward
  ----------------------------------------*/
  for(angle = 0; angle < 90; angle += 1)     //change the angle of the pen from 0 to 90
  {                                  
    servo_test.write(angle);      //command to rotate the servo to the specified angle              
  }
 
}

void stepMeHigh(int motor, int dir, int del) { 
 
  /*-----------------------------------------------
  * Function parametres:
  * motor : 1 - motor pen, 2 - motor plate
  * dir : 0 - left, 1 - right
  -----------------------------------------------*/
  
  digitalWrite(DIR_MOTOR_PLATE, dir);
  digitalWrite(DIR_MOTOR_PEN, dir);
  digitalWrite(motor, HIGH);
  delay(del);
  digitalWrite(motor, LOW);
}

void stepStop(){
 
 //nulls the step
  digitalWrite(STEP_MOTOR_PEN, LOW);
  digitalWrite(STEP_MOTOR_PLATE, LOW);
  
}