[Coco] What would a CoCo successor have to have as a minimum?
Theodore (Alex) Evans
alxevans at concentric.net
Sun Nov 21 20:27:19 EST 2010
As far as the bandwidth issue goes, assuming that we are talking about a
25MHz CPU, there are SRAMS that are at least 12x as fast as the CPU, so
interleaved data access lets the "blitter" consume a lot of bandwidth
without interfering with the CPU assuming you latch the data for the CPU
somewhere. Since the CoCo 3 already supported hardware scrolling, you
shouldn't need to blit a full screen just because you are scrolling in
one direction or another. Remember that most old CoCo games did not
redraw the entire screen on a regular basis. With all the talk about
the Amiga, the Amiga did not generally blit the entire screen when
scrolling, and it reduced the memory bandwidth problem by separating
chip and fast memory.
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