In Slave mode The SPIx_MCR has some useless bits it seems.
The CONT_SCKE is it useless??
Is the MTFE useless??
Is the PCSSE useless???
Is the PCSIS useless?? Only the PCS0 is used in slave (confirm please), so the polarity is an option or is fixed to active low?
Is SMPL_PT useless???
Is the bit rate setting useless in slave??
Are the delays useless in slave mode??