encode.py

def encode(clue):
    """Encode a plaintext clue into wheelscii."""
    result = []
    for c in clue:
        if c == '\n':
            result[-1] |= 0x80
        else:
            result.append(ord(c))
    result[-1] |= 0x80
    result[-2] |= 0x80
    return bytes(result)


if __name__ == "__main__":
    from parse_clues import parse_clues
    rom = open('wheel.nes', 'rb').read()
    start, stop = 0x109d0, 0x14618

    data = rom[start:stop]
    assert b''.join(map(encode, parse_clues(data))) == data