from machine import Pin
from time import *
from pin_numbers import *

print('LEDs + button toggle Example')
print('press the button to toggle between 2 LEDs')

r_led = Pin(D1, Pin.OUT)
y_led = Pin(D2, Pin.OUT)
btn = Pin(D8, Pin.IN, Pin.PULL_UP)

btn_val_last = 1

r_led.on()
led_state = 'red'

while True:
  #print('btn =', btn.value())
  # check that the button changed from high to low:
  if btn.value() == 0:  # button value is low
    if btn_val_last == 1:  # last button value was high
      # toggle between yellow and red LEDs:
      if led_state == 'yellow':
        r_led.on()
        y_led.off()
        led_state = 'red'
      elif led_state == 'red':
        r_led.off()
        y_led.on()
        led_state = 'yellow'
      print('led_state =', led_state)
  # update the last button value:
  btn_val_last = btn.value()
  sleep_ms(100)