Re: What are the chances of a Replica II project?

["Chris Morse" <win32mfc@gmail.com>]

Michael J. Mahon wrote:
> Chris Morse wrote:
> > Question is, would it be legal to implement?  Would it be much more
> > difficult to implement?
>
> A little more difficult, but similar.

Well, like Matt mentioned below, have a socket for a ROM chip.
Implement a basic ROM that can be replaced with a real A2 ROM image.

> >>From a legal standpoint, I would assume the ROMs are off limits.
> > Though if you own an Apple II already, would it be illegal to use them
> > in your own electronic designs?
>
> What is strictly "legal" and what is acceptable for people to do in
> the privacy of their own homes are sometimes different.  ;-)

True..

> > Modern computer systems are ill-adapted to learning about computers,
> > especially the hardware-related aspects.  Try to design even a simple
> > board for todays PC architectures.  It would be nice to have a modern
> > kit for an 8-bit computer system (like the Replica I) that was
> > functionally equivelant to a real system (ie, the Apple II.)  I think
> > from an electronics hobbiest/student point of view, it would be more
> > exciting to build a computer system for which there was already a
> > plethora of knowledge and information on.  Candidates for such a system
> > would be an Apple II, C64 and an old IBM-PC (ISA bus).
>
> Finding a *real* Apple II+ is still not hard--though collectors are
> making it harder.   II+ clones may actually be getting easier to find
> than the real thing!  But they certainly qualify, since they are usually
> 100% Apple II+.

I suppose, but (A) it'll eventually get harder (and more expensive),
and (B) my
idea is more in line with the Replica I project - building and
understanding it
yourself.

> > The Replica I has an expansion port, but it's completely different from
> > the Apple II design slot design.  With a "Replica II" type of project,
> > boards designed for such a machine could be plugged directly into a
> > real Apple II.  Nice.
>
> The Apple II peripheral bus was designed as a leap in expandability
> and ease of use.  Truly the first real example of "plug and play".
> I, too, consider implementation of the peripheral bus as a necessity
> for any modern replica.
>
> Most "replicas" that are being discussed are not TTL replicas, which
> would be easy to probe and understand, but are FPGA replicas, in which
> the machine exists entirely within one chip, as "source code" for the
> logic equations.  I leave it to you to decide which is more transparent
> for your purposes.
>
> -michael

I was thinking more along the lines of the Replica I project where you
*could* breadboard it, or get a kit with PCB and parts, and "get your
hands
dirty" and learn fundamental computer architecture.  Modify the design,
etc.
FPGA-based systems may certainly be the future, but it's not the same
sort hands-on electronics learning, IMHO.  At that point, it's more
VHDL
programming.  I suppose I am favoring "retro" hardware too.

Cheers,
// CHRIS