4-bit_full_adder.py

# Mr. Coxall
# This Micro:Bit Python code goes through all the combinations of 2 44-bit positive binary numbers

from microbit import *

# variable holding the decimal value of a button
a_input = 0
a_input_as_binary = []
b_input = 0
b_input_as_binary = []


def convert_decimal_to_binary(decimal_number, input_letter):
  # this function accepts a decimal number 
  # and converts it to the binary equivalent
  # it returns the binary number in a list
  
  if isinstance(decimal_number, int) and decimal_number <= 15 and decimal_number >= 0 and isinstance(input_letter, str) and (input_letter == "A" or input_letter == "B"):
    remainder_stack = []

    while decimal_number > 0:
        remainder = decimal_number % 2
        remainder_stack.append(remainder)
        decimal_number = decimal_number // 2

    binary_number = []
    while not remainder_stack == []:
        binary_number.append(remainder_stack.pop())
        
    # if not returning 4 digits, add leading 0s
    while not len(binary_number) == 4:
        binary_number.insert(0, 0)
        
    return binary_number
  
  else:
    return "error"


pin0.write_digital(0)
pin1.write_digital(0)
pin2.write_digital(0)
pin8.write_digital(0)
pin12.write_digital(0)
pin13.write_digital(0)
pin14.write_digital(0)
pin15.write_digital(0)

display.show(Image.YES)
sleep(500)

while True:
    display.clear()
    
    for b_input in range(0, 15+1):
        for a_input in range(0, 15+1):
            # convert decimal to binary
            a_input_as_binary = convert_decimal_to_binary(a_input, "A")
            b_input_as_binary = convert_decimal_to_binary(b_input, "B")
            
            # turn on the digital pins
            pin0.write_digital(int(a_input_as_binary[3]))
            pin1.write_digital(int(a_input_as_binary[2]))
            pin2.write_digital(int(a_input_as_binary[1]))
            pin8.write_digital(int(a_input_as_binary[0]))
            
            pin12.write_digital(int(b_input_as_binary[3]))
            pin13.write_digital(int(b_input_as_binary[2]))
            pin14.write_digital(int(b_input_as_binary[1]))
            pin15.write_digital(int(b_input_as_binary[0]))
            
            display.scroll(str(a_input) + "+" + str(b_input) + "=" + str(a_input+b_input))