Building a better "old" computer - test-drb@ccmp.vtda.org

25 Jun 2000

...
 Even better.. Today you could use one of the modern
chips (pentium) to emulate
...
 the Z80, probably at unheard of speeds, with full
access to all the internal
...
 registers (after all the pentium would be keeping those
registers in memory
...
 somewhere..) 
You could and then you have one of the Z80 emulators.
...
 Using original parts we may not be able to make a
better computer than then, but
...
 using modern parts, perhaps we can make it smaller and
faster, even using a Z80
...
 memory is denser (and cheaper) today than then, right?
<imho> 
using a standard Z84C010 (cmos 10mhz) and common cache rams I could
easily do a z80 1mb 10mhz machine.  It's not hard.  Use a Z180S00 and
33mhz
is possible.  With cheap, dense fast static memory most of the old
designs
get real simple and can go faster.  The best example is a proto I've
build using
a Z84C50 (z80/10mhz with clock + wait state management, 1k ram) in a
clone
of the amproLB using static ram (eliminates 15 DIPS) making is a fairly
bare
board.  It runs at 8mhz due to limits in the SIO and CTC parts I had.  I
wanted
it to run the same boot and BIOS so I used what I had.
If I were to do the latest and greatest I'd go with Z380 as it will run
Z80 native
and make the IO a z180 slave, then the only limits would eb the how fast
can
the Z380 go (20mhz is common part and it executes Z80 instructions in
about
half the clocks).
Allison
...

Ernest wrote:
> Based on what the current computer industry knows about building computers,
...
 > would it be possible to build a better Z80 based
computer today, using the
...
 > same chips that the builders in, say, 1979 had
available?
>
> I heard someone say that the manufacturers did the best they could with what
...
 > they had to work with "back then," and I
started to wonder if we could do it
...
 > better today. Has our understanding of how it all
works improved enough to
...
   do it better
now, using the same chips, etc.?
 Just curious,
 Ernest 