def int16_to_bits(x):
    """
    Unpack a 16 bit integer into binary fields. See the syntax for
    this here https://docs.python.org/3/library/string.html#format-specification-mini-language
    
    Parameters
    ----------
    x : int16
        single integer.

    Returns
    -------
    List of binary fields aligned so int16_to_bits(1024)[0] = bit 0

    """
    assert isinstance(x, int), 'x should be integer'
    return [int(b) for b in f'{x:016b}'.format(x)[::-1]]