8088 vs. 80c88

[Allison]

>
>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:
>
>> 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.
> 

There was that too.


>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