from machine import Pin
import utime

LED = Pin(0, Pin.OUT)
Faster = Pin(1, Pin.IN, Pin.PULL_UP)
Slower = Pin(2, Pin.IN, Pin.PULL_UP)
dly = 1

def Flash_Faster(Faster):
    global dly
    dly = dly - 0.1
    print ('rapido',dly)
def Flash_Slower(Slower):
    global dly
    dly = dly + 0.1
    print('lento',dly)
Faster.irq(handler=Flash_Faster,trigger=Faster.IRQ_FALLING)    
Slower.irq(handler=Flash_Slower,trigger=Slower.IRQ_FALLING)

while True:
    LED.value(1)
    utime.sleep(dly)
    LED.value(0)
    utime.sleep(dly)