FPU going too slow
Hi Florent,
Yes the main reason to run slower may be to save power; however if you carefully use WFI (or WFE) for sleeping when you don’t have anything to do (waiting to be woken up by some interrupt, even masked for WFI, only unmasked ones for WFE) then you may achieve about the same power consumption at 100MHz, but have better response times due to the higher CPU frequency.
Of course this is only valid if you are interrupt-driven; if you use polling, you can’t use WFI/WFE and then decreasing teh CPU frequency to what gives you the needed performance will provide you with better battery life.
Bernard (Ac6)