These bits are written by software to insert the bus turnaround delay after a read access only from multiplexed NOR Flash memory to avoid bus contention if the controller needs to drive addresses on the databus for the next side-by-side transaction.
Now my PSRAM is not
NOR Flash and does not multiplex the data and address lines, so I assumed that
FSMC_BusTurnAroundDuration is a "don't care" in my case. However, when I set
FSMC_BusTurnAroundDuration = 0;
then the ARM crashes. Any value between 1 and 15 doesn't crash the ARM.
Why is the bus turn around duration relevant for my PSRAM?