ARM, RISC-V контроллеры

Для F1 - не нужно, для F0 - можно и нужно. Совсем же недавно обсуждалось, но повторенье, мать его! 

Из RM на F0 (DM00031936):

When the data frame size fits into one byte (less than or equal to 8 bits), data packing is

used automatically when any read or write 16-bit access is performed on the SPIx_DR

register. The double data frame pattern is handled in parallel in this case. At first, the SPI

operates using the pattern stored in the LSB of the accessed word, then with the other half

stored in the MSB. Figure 274 provides an example of data packing mode sequence

handling.