from machine import Pin
import utime

LED = Pin(1, Pin.OUT)  # LED at pin GP1
Faster = Pin(2, Pin.IN)  # Faster at pin GP2
Slower = Pin(3, Pin.IN)  # Slower at pin GP3
dly = 1.0  # Default delay

# This is the interrupt service routine. Whenever pushbutton
# Faster is pressed, the program jumps here and decrements
# delay to make the flashing faster
def Flash_Faster(Faster):
    global dly
    dly = dly - 0.1

# This is the interrupt service routine. Whenever pushbutton
# Slower is pressed, the program jumps here and increments
# delay to make the flashing slower
def Flash_Slower(Slower):
    global dly
    dly = dly + 0.1

# Configure the external interrupts
Faster.irq(handler=Flash_Faster, trigger=Faster.IRQ_FALLING)
Slower.irq(handler=Flash_Slower, trigger=Slower.IRQ_FALLING)

# Main program loop
while True:
    LED.value(0)  # LED ON
    utime.sleep(dly)  # Delay dly
    LED.value(1)  # LED OFF
    utime.sleep(dly)  # Delay dly