How to Build a Split-Flap Clock Digit with ESP32

#include <Arduino.h>
#include <Stepper.h>

#define STEPS_PER_REV 2048
#define MOTOR_IN1 16
#define MOTOR_IN2 17
#define MOTOR_IN3 18
#define MOTOR_IN4 19
#define HALL_PIN 34
#define HOME_THRESHOLD 1800
#define FLAP_COUNT 10
#define STEPS_PER_FLAP 205

Stepper flapMotor(STEPS_PER_REV, MOTOR_IN1, MOTOR_IN3, MOTOR_IN2, MOTOR_IN4);
int currentDigit = 0;

bool magnetDetected() {
  return analogRead(HALL_PIN) < HOME_THRESHOLD;
}

void stepForward(int steps) {
  flapMotor.step(steps);
  delay(80);
}

void homeWheel() {
  Serial.println("Homing split-flap wheel...");
  for (int i = 0; i < STEPS_PER_REV + 300; i += 4) {
    if (magnetDetected()) {
      currentDigit = 0;
      Serial.println("Home magnet found");
      return;
    }
    stepForward(4);
  }
  Serial.println("Home magnet not found. Check sensor alignment.");
}

void showDigit(int targetDigit) {
  targetDigit = constrain(targetDigit, 0, FLAP_COUNT - 1);
  int delta = (targetDigit - currentDigit + FLAP_COUNT) % FLAP_COUNT;
  stepForward(delta * STEPS_PER_FLAP);
  currentDigit = targetDigit;
  Serial.printf("Showing digit %d\n", currentDigit);
}

void setup() {
  Serial.begin(115200);
  analogReadResolution(12);
  pinMode(HALL_PIN, INPUT);
  flapMotor.setSpeed(12);
  delay(500);
  homeWheel();
}

void loop() {
  for (int digit = 0; digit < FLAP_COUNT; digit++) {
    showDigit(digit);
    delay(1200);
  }
}

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