# https://dev.to/blues/a-practical-look-at-pio-on-the-raspberry-pi-pico-50j8

import time
import rp2
from machine import Pin


#@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW, out_shiftdir=rp2.PIO.SHIFT_LEFT)
@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW)  
def blink4():
    set(pins, 1)
    set(x, 10)
    label("loop_0")
    set(y, 10)
    label("loop_1")
    nop().delay(6)
    jmp(y_dec, "loop_1")
    jmp(x_dec, "loop_0")   
    set(pins, 0)
    set(x, 10)
    label("loop_2")
    set(y, 10)
    label("loop_3")
    nop().delay(6)
    jmp(y_dec, "loop_3")
    jmp(x_dec, "loop_2")   
  
    wrap()

sm = rp2.StateMachine(0, blink4, freq=2_000, set_base=Pin(16))

sm.active(1)
time.sleep(10)
sm.active(0)