# John Kristofer A. Go
# BSCPE-4A

from rp2 import PIO, StateMachine, asm_pio
from machine import Pin
import time

@asm_pio(set_init=(PIO.OUT_LOW,))
def stepper_motor_program():
    wrap_target()
    set(pins, 1)  [31]  # High step pulse
    set(pins, 0)  [31]  # Low step pulse
    wrap()

DIR_PIN = Pin(18, Pin.OUT)   
STEP_PIN = Pin(19, Pin.OUT)  
BUTTON_PIN = Pin(1, Pin.IN, Pin.PULL_UP) 
LED_PIN = Pin(2, Pin.OUT)   

# StateMachine to control stepper motor
sm = StateMachine(0, stepper_motor_program, freq=10000, set_base=STEP_PIN)

def blink_led():
    LED_PIN.toggle()  
    time.sleep(0.25)  # Delay for 0.25 seconds (2 Hz blinking)

# Main loop
while True:
    if BUTTON_PIN.value() == 0:  # Button pressed
        DIR_PIN.on()  # Set motor to turn clockwise
        LED_PIN.on()  
        if not sm.active():  
            sm.active(1)
        time.sleep(0.1)  # Wait for 0.1 seconds (10 Hz step rate)
    else: 
        if sm.active():  # Stop motor if it is running
            sm.active(0)
        blink_led()  # Blink LED at 2 Hz