CoCo vs. C64 duke it out

[Jim Brain]

woodelf wrote:
>
> I suspect any OS using the 6502 can't have multi-tasking OS
> because you can't change page 0 or the stack page.
Define "change"?  LUnix and BOS (unfinished multitasker from the creator 
of ACE), as well as my BRIX could "change" zpage and stack on a 6502.  
It took either using the REU DMA or simply copying the page to another 
location in memory, but it worked.

Jim