With the assitance of a few folks on and of the board I've made some progress into understanding the inner working of my pxa 255 powered Axim. The aim is to obtain full and proper control of the frame buffer and enable things like hardware swapping of buffers, thus avoiding those nasty blits. There's plenty of documentation out there, and a lot can be gleened from device drivers written for non-windows OS. Check out http://openwince.sourceforge.net
Also, there's an old article about mapping pointers to hardware registers to be found at :
http://columns.pocketnow.com/content.cg ... cals&id=14
and some further code here:
http://www.elevatedstudios.com/pocket/source.htm
and a recent post (ipaq 36xx) on egroups :
http://groups.yahoo.com/group/Pocket-PC ... ssage/4969
And of course, required reading :
Intel PXA255 Processor Developes Manual (278693-001.pdf) section 7.6
After all this, I'm still some way of getting anything to work. I can read registers like to OS Timer, but the LCD address registers always return 0 to me. Control of the LCD buffering is via a 4 dword structure call a Frame Description, which contains a pointer to the video buffer. The PXA255 docs suggest that multiple Frame Descriptors can in effect be chained together, which may allow hardware page flipping. Perhaps all this has to be done with the LCD disabled.
By posting these rambling I'm hoping someone with more experience can add to the base knowledge and perhaps help define what is, and isn't possible.