Well, Allison, it appears you're right. The AMD 9080 was the one with the 250ns
clock (4 MHz) period, now that I've looked a couple of references. Thanks for
clearing that up.
However, that doesn't explain what's going on in my iSBC8020-4's. I'll
have to
figure that one out.
Dick
----- Original Message -----
From: "ajp166" <ajp166(a)bellatlantic.net>
To: <classiccmp(a)classiccmp.org>
Sent: Sunday, September 30, 2001 5:12 PM
Subject: Re: 8080 vs. 8080A
no, it was 2mhz.
using 8224 the usual crystal was 18.435 (2.0483333*9).
there was a -1. -2 and -3 version of the part but the fastest was 3mhz.
I used to sell upD8080AF for NEC and I had to know my competition.
Allison
-----Original Message-----
From: Richard Erlacher <edick(a)idcomm.com>
To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org>
Date: Sunday, September 30, 2001 6:23 PM
Subject: Re: 8080 vs. 8080A
BTW, the 8080 was a 2.5 MHz part, wasn't it?
I've got a couple Intel
app-notes
where they generate a baud-rate clock from 24.576
MHz and generate the
CPU clock
from that, at 2.4576 MHz for the CPU. That's
on an i8080-2.
Dick
----- Original Message -----
From: "ajp166" <ajp166(a)bellatlantic.net>
To: <classiccmp(a)classiccmp.org>
Sent: Sunday, September 30, 2001 2:31 PM
Subject: Re: 8080 vs. 8080A
> Wrong!
>
> The I8080A is AS fast as the i8080. the i8080A-1 is faster but not
twice
> as the fastest 8080[A] was only 3mhz and hte
standard part was 2mhz.
>
> Allison
>
> -----Original Message-----
> From: John Galt <gmphillips(a)earthlink.net>
> To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org>
> Date: Sunday, September 30, 2001 3:57 PM
> Subject: Re: 8080 vs. 8080A
>
>
> >"The i8080A is essentially twice as fast as the
> > standard i8080 and COULD be used more easily with low-power logic
since
> its
> >demands aren't as stringent".
> >
> >Ok, that's a good start.
> >
> >But, I don't think "low power" TTL (transistor transistor logic)
had
> >anything to do with the complexity of the code being executed on the
> chip.
> >True? I had assumed
> >that the references to the 8080 only being compatible
> >with "low-power TTL" and the 8080A being compatible
> >with "standard TTL" had something to do with the support chips (Ram,
> clock,
> >etc) that could be used with the 8080 vs. the 8080A.
> >
> >Since I'm new to this mail list, let me explain why I would
> >show up here and ask such a question to begin with.
> >
> >I'm a chip collector. I am trying to document the differences
between
> the
> >different early Intel microprocessors. Not worried about massive
> detail,
> >just the major differences (PMOS, vs. NMOS, vs.
> >HMOS, clock speed, transistor count, etc).
> >
> >The only microprocessor that I don't have a good handle
> >on is the 8080 and the difference between the 8080 and 8080A.
> >
> >I also know that the 8080 was introduced sometime
> >around April 1974. I have not been able to find an
> >introduction date for the 8080A. Was it introduced at
> >the same time? Does anyone know?
> >
> >I also need an Intel C8080 or C8080-8 for my
> >collection. If you have one, I want it. I have been looking
> >for one for months and have not been able to find one.
> >If you have either of these chips in good condition
> >(no desoldered parts wanted), I'm offering 400.00
> >for the C8080-8 and 500.00 for a C8080.
> >
> >If you need a replacement for the C8080 or C8080-8 you sell me, I'll
> GIVE
> >you a D8080A free as part of the
> >deal.
> >
> >----- Original Message -----
> >From: "Richard Erlacher" <edick(a)idcomm.com>
> >To: <classiccmp(a)classiccmp.org>
> >Sent: Sunday, September 30, 2001 1:21 PM
> >Subject: Re: 8080 vs. 8080A
> >
> >
> >> This makes no sense at all, though it may be because I'm
> misinterpreting
> >the way
> >> in which you've put it.
> >>
> >> I have Intel boards that come in versions with the i8080 and also,
> >> optionally,with the i8080A, and, aside from the clock frequency and
> memory
> >> access times, they're identical. The i8080A is essentially twice
as
> fast
> >as the
> >> standard i8080 and COULD be used more easily with low-power logic
> since
> >its
> >> demands aren't as stringent.
> >>
> >> The i8080A will, AFAIK, replace the i8080 in all applications
without
> ill
> >> effects.
> >>
> >> BTW, please turn off "rich-text" mode in your email editor when
you
> >compose
> >> messages for this group, as some folks' mail readers can't
interpret
the
> rich-text/HTML format.
>
> Dick
> ++++++++++++++++++++++++++++++++++++++
> ----- Original Message -----
> From: John Galt
> To: classiccmp(a)classiccmp.org
> Sent: Sunday, September 30, 2001 10:17 AM
> Subject: 8080 vs. 8080A
>
>
> Can anyone here describe the technical differences between
> an Intel 8080 and Intel 8080A CPU?
>
> The ONLY ref. I have been able to find seems to indicate that there
was a
bug in
> the 8080 and as a result it would only work with low power TTL?
>
> The problem was fixed in the 8080A and it would work with standard
TTL?
>
> Does this make sense to anyone?
>
> Could anyone put this into laymans terms for me?
>
> Thanks,
>
> George Phillips - gmphillips(a)earthlink.net
>