TB6600 Stepper Motor Driver Tutorial, Easily Master Motor Control Techniques  

				
					// Pin definition
#define PULSE_PIN 2  // Pulse signal
#define DIR_PIN   3  // Direction signal
#define ENA_PIN   4  // Enable signal

// Parameter settings (focus on modifying time ratios)
const int minDelay = 300;     // Maximum speed (fastest)
const int maxDelay = 3000;    // Initial/end speed (slowest)
const int step = 15;          // Acceleration/deceleration step (smoothness)
const unsigned long runTime = 10000;  // Total runtime per direction (still 10 seconds)
const float accelRatio = 0.2;  // Acceleration phase ratio (20% → 2 seconds, unchanged)
const float decelRatio = 0.5;  // Deceleration phase ratio (50% → 5 seconds, extended deceleration)
// Constant speed phase ratio = 1 - 0.2 - 0.5 = 0.3 → 3 seconds (target value)

void setup() {
  pinMode(PULSE_PIN, OUTPUT);
  pinMode(DIR_PIN, OUTPUT);
  pinMode(ENA_PIN, OUTPUT);
  
  digitalWrite(ENA_PIN, LOW);  // Enable driver
  delay(100);  // Wait for initialization
}

void loop() {
  // Forward rotation for 10 seconds (2s acceleration → 3s constant speed → 5s deceleration)
  digitalWrite(DIR_PIN, HIGH);
  runWithSmoothSpeed(runTime);
  
  // Reverse rotation for 10 seconds (same as above)
  digitalWrite(DIR_PIN, LOW);
  runWithSmoothSpeed(runTime);
}

// Core function: Implements acceleration → constant speed → deceleration process
void runWithSmoothSpeed(unsigned long totalTime) {
  unsigned long startTime = millis();
  int currentDelay = maxDelay;  // Start from the slowest speed
  int stage = 0;  // 0=acceleration, 1=constant speed, 2=deceleration

  while (millis() - startTime < totalTime) {
    unsigned long elapsed = millis() - startTime;
    float progress = (float)elapsed / totalTime;  // Running progress (0~1)

    // 1. Acceleration phase (first 20% of time → 2 seconds)
    if (stage == 0) {
      if (progress < accelRatio) {
        if (currentDelay > minDelay) {
          currentDelay -= step;
          if (currentDelay < minDelay) currentDelay = minDelay;
        }
      } else {
        stage = 1;  // Enter constant speed phase
      }
    }
    // 2. Constant speed phase (middle 30% of time → 3 seconds)
    else if (stage == 1) {
      if (progress >= (1 - decelRatio)) {  // When progress exceeds 50% (1-0.5=0.5), enter deceleration
        stage = 2;
      }
      // Maintain maximum speed (currentDelay=minDelay)
    }
    // 3. Deceleration phase (last 50% of time → 5 seconds)
    else if (stage == 2) {
      if (currentDelay < maxDelay) {
        currentDelay += step;
        if (currentDelay > maxDelay) currentDelay = maxDelay;
      }
    }

    // Output pulse
    digitalWrite(PULSE_PIN, HIGH);
    delayMicroseconds(currentDelay / 2);
    digitalWrite(PULSE_PIN, LOW);
    delayMicroseconds(currentDelay / 2);
  }
}