from machine import Pin
import time

bn1 = Pin(27, Pin.IN, Pin.PULL_UP)
bn2 = Pin(14, Pin.IN, Pin.PULL_UP)
bn3 = Pin(12, Pin.IN, Pin.PULL_UP)
bn4 = Pin(13, Pin.IN, Pin.PULL_UP)

while True:
    b1 = 0 if bn1.value() else 1
    b2 = 0 if bn2.value() else 1
    b3 = 0 if bn3.value() else 1
    b4 = 0 if bn4.value() else 1

    value = (b1) + (b2 << 1) + (b3 << 2) + (b4 << 3)
    print("Binary value:  ", int(b1), int(b2), int(b3), int(b4))
    time.sleep(0.1)
    print("Decimal value: ", int(value))
    time.sleep(0.1)