Re: FPGA musings

[bieling@terra.es (Jorge Chamorro Bieling)]

Michael J. Mahon <mjmahon@aol.com> wrote:

> Jorge Chamorro Bieling wrote:
> > Sean Fahey <a2fan@hotmail.com> wrote:
> > 
> > 
> >>There is a 4MHz Zip Chip on eBay right now.
> > 
> > 
> > hehe $102, and going up, and 5 days left...
> > 
> > Can someone please re-design a zipchip with a fpga (this time with more
> > than 8mhz).. ???
> > 
> > It looks like the price isn't going to be a problem.. :-)
> 
> While everyone seems to be getting off on the idea of putting lots
> of fancy stuff into FPGAs, there is something that needs to be
> considered...designing complex hardware is no easier (and arguably
> harder) than designing complex software!
> 
> It's a lot more than a weekend project to design a Zip Chip.  ;-)
> 

This can't be called "complex hardware", it's not at all by todays
standards. You see, there are too many, more complex, pipelined
microprocessor ip cores designed by individuals *just for fun*. 
Nowadays these hdl things let you comfortably "write" hardware that you
can put so easily in silicon... 
It has nothing to do with the good old way of lotsOfDatabooks +
lotsOf74lsxx + pen + paper + drawingSchematics + karnaughMapping +
checkingDelays + checkingFanOuts + protoBoarding + wireWrapping +
soldering + oops! + correctThis + watchForGlitches + watchTheNoise +
connectFloatingInputs + haveaLookWithTheScope + burnTheEPRomAgain +
someMoreDecouplingCapacitors + etc etc. Most Ataris and Commodores have
been already fpga'ed just for fun. 

The apple2 community is not up to date in this sense... :-(

To make it easier the 6502 could be left out of the fpga by using an off
the shelf WDC part. Then only cache/glue/sinchronization logic would
have to be designed , hdl'ed (written!) and fpga'ed. You would get at
much 14x the speed though. Maybe use a 6502 ip core for more speed. Or
use a readily available risc ip core and emulate the 6502 in software. C
sources are readily available. Or who knows what, there's people that
knows so much more than I. But I don't see any essential thing I'm
missing here. It looks so plausible.

In fact, it's a perfect project for people that have the time, that have
the know-how, that spend the time reading daily things like
comp.sys.apple2, people like... you. And probably others like you that
are also coming here to comp.sys.apple2 often but for some reason don't
seem to talk much. Maybe some people who designed apple2 things in the
past... who knows.

Come on!
-- 
Jorge Chamorro Bieling