Joystick Example

sketchbook.ino

#include "thumbstick.h"

// set pin numbers for switch, joystick axes, and LED:
const int switchPin = 6;    // switch to turn on and off mouse control
const int xAxis = A0;       // joystick X axis pin
const int yAxis = A1;       // joystick Y axis pin

class MenuListener {
  public:
  bool press();
  void release(const int ms);
};

bool MenuListener::press() {
  return true;
}

void MenuListener::release(const int ms) {

  if (ms > 7000) {
    // system reset
    Serial.println("RESET");
  } else if (ms > 3000) {
    // extra
    Serial.println("Extra");
  } else {
    // normal click release, take some action.
    Serial.println("Select");
  }
}

// Singleton instances
MenuListener menuListener = MenuListener();
ThumbstickButton button = ThumbstickButton(6, xAxis, yAxis, (PressButton)&menuListener.press, (ReleaseButton)&menuListener.release);

void setup() {

  Serial.begin(115200);

}

void loop() {

  if (button.pushed()) {

  }
  
  ThumbstickPosition p = button.position();

  if (p.x != 0 || p.y != 0) {
    char jxy[30];
    sprintf(jxy, "%i,%i %i,%i\0", p.x, p.y, p.dx, p.dy);
    Serial.println(jxy);
  }
  
  delay(5);
  
}

thumbstick.h

#include "Arduino.h"

typedef bool (*PressButton) ();
typedef void (*ReleaseButton) (const int ms);

class ThumbstickPosition {
  public:
    int x = 0;
    int y = 0;
    int dx = 0;
    int dy = 0;
    
    ThumbstickPosition();
    ThumbstickPosition(const int x, const int y, const int dx, const int dy);

  private:
  
    bool motion = false;
};

class ThumbstickButton {
  public:

    ThumbstickButton(const int pin, const int xAxis, const int yAxis, PressButton btnPress, ReleaseButton btnRelease);
    bool pushed();
    unsigned long age();
    ThumbstickPosition position();
  
  private:
    int pin;
    int xAxis;
    int yAxis;
    
    unsigned long since = 0;
    PressButton btnPress;
    ReleaseButton btnRelease;
    ThumbstickPosition positions[2];
    
    bool pressed = false;
    int8_t peek = 0;
    int8_t current = 0;
    int8_t previous = 0;
    
    int8_t read();
    int readAxis(int axis);
};

thumbstick.cpp

#include "thumbstick.h"


// parameters for reading the joystick:
const int range = 128;    // output range of X or Y movement
const int threshold = 8;  // resting threshold

ThumbstickPosition::ThumbstickPosition() {
  
}

ThumbstickPosition::ThumbstickPosition(const int x, const int y, const int dx, const int dy) {
  this->x = x;
  this->y = y;
  this->dx = dx;
  this->dy = dy;
}

ThumbstickButton::ThumbstickButton(const int pin, const int xAxis, const int yAxis, PressButton btnPress, ReleaseButton btnRelease) {
  this->pin = pin; 
  this->xAxis = xAxis;
  this->yAxis = yAxis;
  this->btnPress = btnPress;
  this->btnRelease = btnRelease;
  pinMode(pin, INPUT_PULLUP);  // the switch pin
}

unsigned long ThumbstickButton::age() {
  return millis() - this->since;
}

int8_t ThumbstickButton::read() {
  int8_t r = digitalRead(this->pin);  // 1=up or 0=down.

  if (r == this->peek) {
    if (millis() - this->since > 40) {
      this->previous = this->current;
      this->current = r;
    }
  } else {
    // state changed
    
    this->peek = r;
    if (this->current == LOW && r == HIGH) {
      // button released
      const int ms = millis() - this->since;
      this->previous = this->current;
      this->current = r;
      this->pressed = false;
      this->btnRelease(ms);
    }
    
    this->since = millis();
  }
  
  return this->current;
}

bool ThumbstickButton::pushed() {
  if (this->read() == LOW) {
    uint32_t lastPress = millis();
    if (!this->pressed) {
      return this->pressed = this->btnPress();
    }
  }
  return false;
}

ThumbstickPosition ThumbstickButton::position() {
  this->positions[1] = this->positions[0];
  const int x = this->readAxis(xAxis);
  const int y = this->readAxis(yAxis);
  
  return this->positions[0] = ThumbstickPosition(x, y, x - this->positions[1].x, y - this->positions[1].y);
}

int ThumbstickButton::readAxis(int axis) {
  /*
  reads an axis (0 or 1 for x or y) and scales the analog input range to a range
  from 0 to <range>
 */

  // read the analog input:
  int reading = analogRead(axis);

  // map the reading from the analog input range to the output range:
  reading = map(reading, 0, 1023, 0, range);

  // if the output reading is outside from the rest position threshold, use it:
  int distance = reading - (range / 2);

  if (abs(distance) < threshold) {
    return 0;
  }

  // return the distance for this axis:
  return distance;

}