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Re: RFC : SOME IDEAS FOR THE APPLE II FPGA'ers
mdj wrote:
Michael J. Mahon wrote:
And, though you've described some characteristics of a solution that
you prefer, you haven't shared what your *objective* is--from which
those requirements are derived.
From what you've said, I'm having a hard time understanding why
you aren't satisfied with a real Apple II. It would seem to satisfy
all the characteristics you describe, is inexpensive, reliable, and
generally easy to fix. The only thing that doesn't get you is the
fun of playing with FPGAs. ;-)
Sorry, I thought my objective was implied. Essentially what I'm
interested in is preservation. I am, in essence, satisfied with my real
Apple II, however, several of it's components are now extremely
difficult to replace, should they bite the dust. Despite several years
of searching, I've not found an 8Mhz Zip Chip to replace my Transwarp,
They come up on eBay once or twice a year, and occasionally on
csa.marketplace. Admittedly, they usually go for over $100...
There does seem to be general interest in an accelerator design,
so one may yet show up as a new product for enthusiasts.
and the RGB adapter module on the back of my RamWorks III isn't exactly
an easy to locate item.
But there are lots of other RGB adapters and RAM cards. I've never
used an RGB adapter, so it's pretty easy for me to live without one. ;-)
Ideally, I'd like to be able to put these items
away and not use them.
That almost certainly will not prolong their life. Go ahead and
use them. Almost all IC failures after infant mortality (3 months)
and before old age (>30 years ;-) are very low incidence random
failures--unless they are severely mistreated. And most of the
IC's in Apples and their peripherals are standard parts (but not all).
It's better to die booted than sitting in a desk drawer. ;-)
The SCSI card too, is a hard to replace item,
although GSE-Reactive make take care of this soon. It's likely though,
that I'll switch to a more convenient form of mass storage.
Exactly. My CFFA cards have enabled me to unplug my SCSI cards
without any feeling of loss (not that I don't want to keep them ;-).
I'm also
rather attached to my Workstation card, which allows me to mount
fileshares from my main computer (A linux box which runs Netatalk, the
Apple IIe is connected to the household network via an Asante ethernet
adapter). Despite the modest speed, it is by far the most convenient
way to transport data back and forward from the IIe I've found, since
it's the only one AFAIK that integrates seamlessly into the ProDOS 8
environment. (with the exception that ProSEL utilities, which are among
my Apple II favorites, tend to utilise low level ProDOS calls which
aren't supported by the AppleShare protocol)
Bummer--ProSEL utilities are among my favorites, too. They work
fine on a CFFA card. ;-)
Being realistic, a lot of these devices are unlikely to still be in
operating order in 20 years. It's a credit to Apple and Applied
Engineering that they all work perfectly now. Over time, I've had RAM
chips go bad on the RamWorks, one on the Transwarp (that was tricky to
find let me tell you, it was in the bank that caches auxiliary ram
cards).
I think it's safe to say that we don't really know the life expectancy
of the chips. Every year for the past 20 years, someone has said,
"Well, the chips in our machines are going to start failing soon."
Eventually, of course, they will be right--but they haven't been
right yet! Frankly, if we were going to be inundated with mass
chip failures in five years, there would be a lot of them going
bad *today*. Since that apparently hasn't happened, I feel it's
safe to conclude that doomsday is still way in the future.
And by the time that you've reverse-engineered exactly what an ASIC
does, you have all the information required to simply replace it
with a modern programmable part (perhaps on a socket adapter board).
So at a minimum, what I'd *like* is a replacement motherboard for my
IIe that includes accelerator functionality, RamWorks style expansion
memory, and ability to drive more modern displays. It doesn't have to
clock at stupidly fast speeds. It should include more than 1mb of
auxiliary RAM (oh how I've longed for one of those 2mb expander
boards).
Hmmm, what exactly do you *do* with all that RAM? I've found that
I'd hardly miss any RAM beyond what's needed to hold a 3.5" disk
nibble image (for 1-pass copies).
It should also include all 7 expansion slots, composite output that
does EXACTLY what the standard output does, game connector, cassette
I/O. The RGB output should be capable of driving either old-school NTSC
frequency monitors, or switched to VGA level frequencies. Since it's so
simple to do on the FPGA, it should provide a DVI-I output connector so
either analog VGA or a digital panel can easily be connected, now and
in a few years time when analog output becomes obsolete. The
implementation should conform to the AppleColor standard for RGB,
meaning I have access to colour text mode, plus double hires mono,
colour, and mixed. Since some older software manages to stuff this up,
an override switch to force mono or force colour would be sensible
(would let me reuse the now defunct character set switch)
Yes, the display issue seems to keep cropping up...yet there appears
to be a huge pool of high-quality RGB-capable NTSC-scan monitors out
there from all the TV studios converting to digital... A little
stockpiling (distributed or centralized) could easily satisfy the
entire Apple II community's needs for the next 40 years or so. ;-)
I figure the auxiliary slot can be ditched, since the board supports
all the functionality this slot was used for. Users of the Microsoft
Premium CP/M card will have to find an alternative solution ;-)
Agreed.
The problem will be that each quite different design is the product of
a "quite different" designer, and the probability of any of the detailed
designs of other "quite different" designers being acceptable to the
first is almost negligible.
I think though, that the 'quite different' aspects are wholly contained
with the FPGA logic. The general goal is FPGA based design that can be
used like a real Apple II. Some want it to be the fasted Apple II
implementation possible, and that's fine, they can have that within the
general principle. Some want to have cycle accurate implementation so
they can use every peripheral card out there. I want that too -
although I'm prepared to forgo an AUX slot in favour of a bigger than
ever manufactured RamWorks + modern display support.
I think you'll find that when the system is the FPGA, then integrating
a lot of uncoordinated subsystem designs will be both difficult and
ugly.
And coordinating subsystem designs requires a *serious* design
methodology that *all* designers buy into--not easy to do.
If someone put a "plastic" platform with a very modular design out there
for others to modify, that could create the environment you describe, so
maybe someone thinks that *that* would be a great project. (Sounds a
little like the C-one, doesn't it? And look how much follow-on work
that fine project has generated... )
It does sound a little C-one like, and I've even considered using one
of those, but it has the limitation of not having an Apple-II bus, and
I'd like something that mimics the Apple IIe motherboard form factor.
I've always been disappointed by the lack of community development the
C-one inspired.
I understand why you are not excited by the C-one itself. And I think
you can see why I'm worried about the necessary excitement--and
committment--in the Apple community being hard to come by, too.
I know I've got a little 'dreamy' in some of these posts, and if I've
offended your sense of pragmatism, I do apologise ;-) Just pointing out
that if one goes as far as to build an FPGA based Apple II board, there
are many, many possibilities for clever extensions that can be achieved
with only some synthesis and a reprogram.
Please don't apologise--some "pragmatic dreaming" is very much in order!
That's why I keep quiet until it seems like it's all just spinning out
of control, rather than converging on something achievable.
Also, I must admit, I've been hanging around here long enough that it
just seems like every year we get spring rains and Apple fancies...
After the seventh or eighth time, with no real results, it gets a
little less enjoyable--particularly as a lurker. ;-)
-michael
Music synthesis for 8-bit Apple II's!
Home page: http://members.aol.com/MJMahon/
"The wastebasket is our most important design
tool--and it is seriously underused."