[Coco] What would a CoCo successor have to have as a minimum?

[Theodore (Alex) Evans]

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.