How to Use a Joystick with ESP32: Complete Beginner’s Guide (Wiring + Code)

// ============================================================
// ESP32 Joystick Reader - Complete Beginner Guide
// Reads X/Y analog values and button state
// ============================================================

// Pin Definitions
#define JOYSTICK_X 34
#define JOYSTICK_Y 35
#define JOYSTICK_SW 15

// Variables for calibration
int xValue = 0;
int yValue = 0;
int swValue = 0;

void setup() {
  Serial.begin(115200);
  
  // Configure button pin with internal pull-up
  // (INPUT_PULLUP means pin reads HIGH when not pressed, LOW when pressed)
  pinMode(JOYSTICK_SW, INPUT_PULLUP);
  
  // Analog pins don't need pinMode setup
  
  Serial.println("ESP32 Joystick Reader");
  Serial.println("=====================");
  Serial.println("Move the joystick and press the button...\n");
  delay(1000);
}

void loop() {
  // Read analog values (0-4095)
  xValue = analogRead(JOYSTICK_X);
  yValue = analogRead(JOYSTICK_Y);
  
  // Read digital button (LOW when pressed, HIGH when not pressed)
  // The ! (NOT) inverts the reading so pressed = true
  bool buttonPressed = !digitalRead(JOYSTICK_SW);
  
  // Map values to -100 to +100 range for easier understanding
  int mappedX = map(xValue, 0, 4095, -100, 100);
  int mappedY = map(yValue, 0, 4095, -100, 100);
  
  // Small dead zone to eliminate jitter at center
  if (abs(mappedX) < 10) mappedX = 0;
  if (abs(mappedY) < 10) mappedY = 0;
  
  // Print to Serial Monitor
  Serial.print("X: ");
  Serial.print(xValue);
  Serial.print(" (");
  Serial.print(mappedX);
  Serial.print(") | Y: ");
  Serial.print(yValue);
  Serial.print(" (");
  Serial.print(mappedY);
  Serial.print(") | Button: ");
  Serial.println(buttonPressed ? "PRESSED" : "released");
  
  delay(50);  // Read 20 times per second (smooth enough, not too fast)
}