from time import sleep_ms
from machine import Pin

rode_led = Pin(16,Pin.OUT)
gele_led = Pin(15,Pin.OUT)
pb_start = Pin(20,Pin.IN)
pb_stop = Pin(21, Pin.IN)

# als je import machine gebruikt
# rode_led = machine.Pin(16,machine.Pin.OUT)
while True:
    start = pb_start.value()
    print(start)
    
    if start == 1:
        rode_led.value(1)
        gele_led.off()
        # rode_led.on()
        sleep_ms(200)
        rode_led.value(0)
        gele_led.on()
        sleep_ms(200)