27/07/2004 03:45:16, Jamie Morken <jmorken@shaw.ca> 
wrote:

>Oops, just found it in the design guide:
>"The GPIOs are not fast-switching devices and do not switch any 
faster than
>10 MHz."

I think that the SA1100 also had such a warning, and its GPIOs 
used to go astonishingly fast. During development, we were able o 
get a 3-intruction loop to wiggle them, on a 200MHz clock...
Not tried on a more recent chip, so dunno - easy enough to 
check, though 
However, what is it that you're contemplating doing that way? 
Sounds like the job for a tiny PLD / FPGA / Scenix micro, rather 
than wasting the other 99.9% of a PXA on something it'll struggle 
to manage. 
(Free (money) design tools for FPGAs are extremely usable - Xilinx 
Webpack stuff has, up until I needed to start embedding 32-bit 
micros in FPGAs, been fine for even some relatively tricky stuff)
If you really must use a micro to do this, I suspect that you'll end 
up trawling thought TI's (or other - I have no experience other 
than TI) madder DSPs, and even then, I'm not sure you'll get near 
200MHz interrupts. FPGAs have to be the way forward. 

Steve