MITS 2SIO serial chip?

From: Ben Franchuk <bfranchuk_at_jetnet.ab.ca>
Date: Wed Dec 19 21:10:29 2001

Ethan Dicks wrote:
> I've always felt (personal impression) that a 4Mhz Z-80 could outperform
> a 1Mhz 6502, but I never got the chance to do any comparisons when faster
> chips (of both kinds) came out. I'd already moved on to 68000s. Because
> I like the 6502, I would hope that a 4Mhz 6502 could do a little better
> than a 4Mhz Z-80, but I'm not certain. The 6502 does have a one-cycle
> pipeline internally, and it does interleave CPU and memory operations
> efficiently (phi2 clock and what not), but I don't know the Z-80 to
> the same depth and can't make a fair comparison myself.

I suspect the memory interweave was a after thought as memory at that
time
was 2x faster than the CPU. The video/dram refresh was a good idea for
the
6502/6800/6089. I am glad I did not have to program the 6502 however.
Nowdays with all the pipelineing, prefetching and other stuff nobody
knows
how slow a cpu can be. At one time I looked at doing a 68000 cpu but the
only
small 68000 was the 68008 and it seemed too slow to be useful.
-- Ben Franchuk --- Pre-historic Cpu's --
www.jetnet.ab.ca/users/bfranchuk/index.html
Received on Wed Dec 19 2001 - 21:10:29 GMT