Typically, the SPI communication outputs the Most Significant bit first, but
some devices or buses may not conform to this standard. In this case, the LSBF bit may
be used to alter the order in which bits are shifted out during the data exchange. In
both Master and Slave mode, the
LSBF bit controls whether data is shifted MSb or LSb first. Clearing the
bit (default) configures the data to transfer MSb first, which conforms to traditional
SPI operation, while setting the bit configures the data to transfer LSb first.