def _getWordCount(start, length, bits):
    """
    Get the number of words that the requested
    bits would occupy.  We have to take into account
    how many bits are in a word and the fact that the
    number of requested bits can span multipe words.
    """
    newStart = start % bits
    newEnd = newStart + length

    totalWords = (newEnd-1) / bits
    return totalWords + 1