Given a bit-pattern expressed an integer number, return a sequence of
        the individual words that make up the pattern. The number of bits per
        word will be obtained from the internal SPI interface.

def _int_to_words(self, pattern):
        """
        Given a bit-pattern expressed an integer number, return a sequence of
        the individual words that make up the pattern. The number of bits per
        word will be obtained from the internal SPI interface.
        """
        try:
            bits_required = int(ceil(log(pattern, 2))) + 1
        except ValueError:
            # pattern == 0 (technically speaking, no bits are required to
            # transmit the value zero ;)
            bits_required = 1
        shifts = range(0, bits_required, self._spi.bits_per_word)[::-1]
        mask = 2 ** self._spi.bits_per_word - 1
        return [(pattern >> shift) & mask for shift in shifts]