def convert36ToAscii(start, chs):
    """Convert decimal address to ascci address

    :param start: NBP adress in decimal reverse:Big Endian Byte Order: The most significant byte (the "big end") of the data is placed at the byte with the lowest address
    :param chs:tsring of all digits and ascii upper
    :return:NBP adress in ASCII
    """

    if start == 0:
        return ''
    chs_len = len(chs)
    ch = chs[start%chs_len]
    return ch + convert36ToAscii(start//chs_len, chs)