bcd_clock.py

# simple script to print the current time in bcd

import time

def digit_to_bcd(num: int) -> list:
    '''
    Convert a single decimal digit (0-9) to a 4-bit BCD.
    Return a list of booleans, each item is a bit.
    '''
    if 0 <= num <= 9:
        return [bool(int(bit)) for bit in f'{num:04b}']
    return ValueError("digit_to_bcd accepts only digits from 0 to 9.")

def get_bcd_time_rows() -> list[str]:
    '''
    Get the current time in HHMMSS format and convert each digit to BCD.
    Return the formatted binary clock as a list of strings, one per row.
    '''
    local_time = time.localtime()
    time_str = f'{local_time.tm_hour}{local_time.tm_min}{local_time.tm_sec}'
    bcd_columns = [digit_to_bcd(int(d)) for d in time_str]  # each nested list is a column, with 4 bits

    # let's zip them for printing, since bcd clocks are vertical

    bcd_rows = zip(*bcd_columns)
    formatted_rows = []

    for row in bcd_rows:
        line = ''
        for col, bit in enumerate(row):
            line += '*' if bit else '.'

            if col % 2 == 1:
                line += ' '   # extra space after every second digit
        formatted_rows.append(line)
    return formatted_rows

def main():
    for row in get_bcd_time_rows():
        print(row)
main()