24 Feb
2009
24 Feb
'09
4:18 a.m.
Subject: Re: 8088 vs. 80c88
From: "Chuck Guzis" <cclist at sydex.com>
Date: Tue, 24 Feb 2009 03:29:14 -0800
To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at
classiccmp.org>
On 23 Feb 2009 at 18:36, Allison wrote:
There was that too.
That it had bugs, can't argue that. They
could have just as easily given
it the base uCOM78 instruction set instead. But how many V20s were bought
to run 8080 rather than as a faster varient of the 8088?
To be certain, almost all of the publications that I saw touting the
V-series chip emphasized the performace aspect. Few even mentioned
the 8080 emulation mode. I was surprised to see emulation extend to
the V40 and V50 uPs.
And almost none mentioned that the V20 implemented many of the 80186
and some of the 80286 instructions.
I've heard reports where the V20 doesn't work
as a drop-in
replacement for an 8080. Must be just enough timing difference that
one works and the other doesn't.
True also. the original IBM PC didn't run it, as well as any cpu other
than intel. Seems there was a minor timing issue that the intel part
tolerent of but no one elses would work.. rumor was it was deliberate.
But most of the 8088 designs were not well cooked and werern't so reliable.
Allison
Cheers,
Chuck