Hey,
I already read the entire Wiki article + the Microchip article, and now I read the pages your linked me to (thanks for that).
1.
I see also in pages 15,17, and also on Wiki, that the data on the MISO/MOSI line stays stable half a (clock's) cycle before the sampling, and half a cycle after the sampling.
Is it a must?
2.
Must the master and slave devices must be configured to have the same CPOL and CPHA values?
If so, what happens if you have one Master (Uc) and 2 Slaves, where one Slave is configured to have CPHA=1, and one slave is configured to have CPHA=0?
(and the slave doesnt give you the option to set their CPHA to a desired value).