Curtis,

Clearly I don't know enough about what you expect to do here, but you need to know that, even with PAL, which has a few more scan lines available than NTSC, you can't really implement a "decent" looking GUI. Even standard VGA is quite inadequate.

Now, if you juts want a point-and-shoot sort of GUI, perhaps what you need is a touch-screen.

A GUI such as is used with Windows of any sort requires things that, while achievable with 805x-type MCU's, would be painfully slow, even with the fastest of them, and requires hardware that would be much more easily implemented with a "larger" microprocessor as opposed to a self-contained, single-chip microcomputer.

I suspect that you have to do much less than a full Windows GUI, though I may be wrong about that. The Windows OS involves tens of millions of lines of code. Of that, it's probable that the GUI consumes between a third and half of that code. I, pessimistically, perhaps, would guesstimate that the typical Windows GUI action that takes a half-second on a 1 GHz Intel CPU might take as little as half an hour or thereabouts on a very fast 805x, and that assumes that you don't have to do anything other than figure out what's been selected with the mouse, and then highlight the icon to signify that it's been selected.

Unless I miss my guess, you can probably get by with something simpler. If not, there are better processor choices than the 805x, which, while at the top of its class, is still somewhat bandwidth limited.

RE