from machine import Pin
from time import sleep

# Assign all out LEDs
led1 = Pin(15, Pin.OUT)
led2 = Pin(14, Pin.OUT)
led3 = Pin(13, Pin.OUT)
led4 = Pin(12, Pin.OUT)

WAIT_TIME = 0.4  # time to wait between each sequence

ALL_LEDS = [led4, led3, led2, led1]
BINARY_NUMS = ['0000', '0001', '0010', '0011', '0100', '0101', '0110', '0111', '1000', '1001', '1010', '1011', '1100', '1101', '1110', '1111']

def show_binary(bin_num):
    for i in range(4):                  # for each digit we have... (4 digits)
        bin_digit = bin_num[i]              # pick out the binary digit
        if bin_digit == '1':                # if it's a 1
            ALL_LEDS[i].value(1)                # turn on it's corroponding LED
        else:                               # if it's anythong else (AKA not a 1)
            ALL_LEDS[i].value(0)                # turn off it's corroponding LED

# main loop
while True:
    for i in range(16):                 # for each binary number we have... (16 total, numbers 0-15)
        show_binary(BINARY_NUMS[i])         # show the binary number on the LEDs
        sleep(WAIT_TIME)                    # wait for some time before showing the next number