【CNC自作②】リミットスイッチ実装｜原点出し（ホーミング）で精度を出す

// テストコード　test_code_XY_SWITCH.ino
#define X_STEP 2
#define X_DIR 5

#define Y_STEP 3
#define Y_DIR 6

#define ENABLE 8

#define X_LIMIT 9
#define Y_LIMIT 10

// ===== 調整パラメータ =====
#define BACKOFF_STEPS 250
#define HOMING_FAST 800
#define HOMING_SLOW 2000

// ===== ホーミング方向 =====
#define X_HOME_DIR HIGH   // ← Xだけ逆にした
#define Y_HOME_DIR LOW    // Yはそのまま

bool stopFlag = false;

void setup() {
  pinMode(X_STEP, OUTPUT);
  pinMode(X_DIR, OUTPUT);
  pinMode(Y_STEP, OUTPUT);
  pinMode(Y_DIR, OUTPUT);
  pinMode(ENABLE, OUTPUT);

  pinMode(X_LIMIT, INPUT_PULLUP);
  pinMode(Y_LIMIT, INPUT_PULLUP);

  digitalWrite(ENABLE, LOW);

  Serial.begin(115200);
  Serial.println("Press 's' to STOP, 'g' to HOME");
}

// ===== 入力チェック =====
void checkInput() {
  if (Serial.available()) {
    char c = Serial.read();
    if (c == 's' || c == 'S') stopFlag = true;
    if (c == 'g' || c == 'G') homeXY();
  }
}

// ===== 停止処理 =====
void stopAll() {
  Serial.println("STOPPED");
  digitalWrite(ENABLE, HIGH);
  while (1);
}

// ===== 1軸ホーミング =====
void homeAxis(int stepPin, int dirPin, int limitPin, bool homeDir) {

  // ① 高速で当たる
  digitalWrite(dirPin, homeDir);
  while (digitalRead(limitPin) == LOW) {
    checkInput();
    if (stopFlag) stopAll();

    digitalWrite(stepPin, HIGH);
    delayMicroseconds(HOMING_FAST);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(HOMING_FAST);
  }

  delay(100);

  // ② BACKOFF（逆方向）
  digitalWrite(dirPin, !homeDir);
  for (int i = 0; i < BACKOFF_STEPS; i++) {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(HOMING_FAST);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(HOMING_FAST);
  }

  delay(200);

  // ③ ゆっくり再接触
  digitalWrite(dirPin, homeDir);
  while (digitalRead(limitPin) == LOW) {
    checkInput();
    if (stopFlag) stopAll();

    digitalWrite(stepPin, HIGH);
    delayMicroseconds(HOMING_SLOW);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(HOMING_SLOW);
  }

  delay(100);
}

// ===== XYホーミング =====
void homeXY() {
  Serial.println("HOMING START");

  homeAxis(X_STEP, X_DIR, X_LIMIT, X_HOME_DIR);
  homeAxis(Y_STEP, Y_DIR, Y_LIMIT, Y_HOME_DIR);

  Serial.println("HOMING DONE");
}

// ===== モーター動作 =====
void moveMotor(int stepPin, int dirPin, bool dir, int steps) {
  digitalWrite(dirPin, dir);

  for (int i = 0; i < steps; i++) {
    checkInput();
    if (stopFlag) stopAll();

    digitalWrite(stepPin, HIGH);
    delayMicroseconds(1000);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(1000);
  }
}

void loop() {
  checkInput();

  stopFlag = false;

  // ===== X軸 =====
  moveMotor(X_STEP, X_DIR, LOW, 300);
  delay(500);
  moveMotor(X_STEP, X_DIR, HIGH, 300);

  delay(1000);

  // ===== Y軸 =====
  moveMotor(Y_STEP, Y_DIR, HIGH, 300);
  delay(500);
  moveMotor(Y_STEP, Y_DIR, LOW, 300);

  delay(2000);
}