from machine import Pin, ADC
import time

# Stepper Motor Pins for A4988
DIR = Pin(26, Pin.OUT)     # Direction pin
STEP = Pin(25, Pin.OUT)    # Step pin
EN = Pin(27, Pin.OUT)      # Enable pin (LOW = ON)

# Input Devices
button = Pin(14, Pin.IN, Pin.PULL_UP)  # Button with pull-up
pot = ADC(Pin(34))                     # Potentiometer
pot.atten(ADC.ATTN_11DB)               # Full range 0–3.3V
pot.width(ADC.WIDTH_10BIT)             # 10-bit resolution (0–1023)

# Enable motor driver
EN.value(0)

motor_running = False   # Motor ON/OFF toggle

def step_motor(delay, direction=1):
    DIR.value(direction)
    STEP.value(1)
    time.sleep_us(int(delay * 1_000_000))   # high pulse
    STEP.value(0)
    time.sleep_us(int(delay * 1_000_000))   # low pulse

print("Stepper with Button + Potentiometer Control")

while True:
    # Button press → toggle motor state
    if button.value() == 0:
        motor_running = not motor_running
        print("▶ Motor Running" if motor_running else "⏹ Motor Stopped")
        time.sleep(0.3)  # debounce delay

    if motor_running:
        # Speed from potentiometer
        pot_value = pot.read()
        delay = 0.0005 + (pot_value / 1023) * 0.01  # 0.5ms – 10ms
        step_motor(delay, direction=1)  # CW direction