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Re: RFC : SOME IDEAS FOR THE APPLE II FPGA'ers
mdj wrote:
Michael J. Mahon wrote:
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. ;-)
There are, you're right, and they're all harder to find than the
Applied Engineering gear, as they were produced in lower quantities. I
have a Checkmate MultiRAM lying around that I don't use, because the
flicker that occurs when the banks are switched drives me nutty.
Ack! I'm sorry to hear that, because I've had a Checkmate for years,
and have been thinking about trying out an RGB monitor with it. ;-(
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. ;-)
Agreed. Although there are other forms of failure: lightning, wierd
power supply failure modes that blow something/everything up, etc. And
there's still the scarcity issue. Eventually, operational heat will
kill components though; I'm convinced every failure I've had is due to
temperature variation eventually either damaging the silicon substrate,
or the interconnects from the packaging to the silicon, so from this
perspective they may 'last longer' in a sealed static bag.
Possible--but surely you aren't worried about scarcity or durability
of 74LS chips...
I'm fortunate to have lived in areas where lightning is not
a problem, but I can sympathize with those who do.
Except for a few chips, heat from their own operation is seldom an
issue. Most heat to which they are exposed is environmental. Either
way, providing cooling is good (though even that can be overdone).
I have had the advantage of growing up with vacuum tubes, transitioning
to transistors, and then to ICs. My experience has been that ICs don't
fail unless you kill them--which I am willing to refrain from doing.
When the end-of-life part of the "bathtub curve" begins to turn up, it
does so gradually, and there will be many years of warning before the
situation becomes dire. It's not a fire drill.
When some preservation solution becomes necessary (and it probably
won't in my lifetime), there will be even better tools and techniques,
and the solution will be both simpler and more elegant than it would
be this year.
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 ;-).
Yeah... I never got around to purchasing one of those... I thought I'd
wait it out until the FPGA era replaces many more things. The CFFA is
very cool, but uses a lot of hardware to accomplish a very simple job
in todays terms.
Ironically, it basically uses an FPGA! ;-)
Bummer--ProSEL utilities are among my favorites, too. They work
fine on a CFFA card. ;-)
Yep. The issue with the Workstation card is that it uses the jump hook
in the ProDOS MLI to attach arbitrary devices. An AppleShare volume,
while it shows up as volume, is not a ProDOS block device, as the
filesystem operations are actually performed by the server, not ProDOS.
This, plus the fact that an AppleShare volume can exceed the normal
ProDOS device size limits, means that block level operations on the
device aren't possible. (The actual filesystem on the other end would
typically be HFS, although in my case it's emulated HFS via AppleDouble
conventions on a UNIX filesystem).
It's a fair tradeoff though, to have Asimov accessible as a ProDOS
filesystem fulltime :-)
That's pretty cool!
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.
See above, but I think for the most part, you are right. It won't stop
me wishing to circumvent potential failure, and guaranteeing
reproduceability for myself, and anyone else who may want it.
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).
True, but it I think it's both more efficient and fun to just reverse
engineer the logical behavior of a peripheral and replace it
holas-bolas with a modern component of equivalent functionality.
Efficiency is a peculiar measure for a nostalgic labor of love...
It's worth a lot to me to keep the case, keyboard, and all the chips
when I take off the top. ;-)
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's more a case of if you're going to do it, do as much as you can
without increasing complexity. And since it's (at least in my mind)
easiest to implement the functionality with a generic 24-bit address
bus to the FPGA I figure there may as well be 16mb of RAM on it. It
opens the device up to a plethora of potential other fun uses without
increased complexity or significantly increased cost (16mb FP mode
SIMMS are a dime a dozen still)
Careful--this way lies madness! ;-)
Remember, I'm motivated by *constrained* resources, and feel that
"limitless" design environments are corrupting. You don't have to
look far to see what I mean...
In terms of actually using the memory on the Apple II, I basically
don't. Although I have been known to use both a slinky card AND the
RamWorks, as the slinky makes a better ramdisk. It means I can keep a
copy of my Apple Pascal environment on my hard disk, and simply image
it onto the slinky card and reboot to that slot. Afterward, I can just
image it back.
The same goes, actually, for DOS3.3 based applications, although I've
never bothered to set this process up. I did consider for a time
imaging most of my favorite DOS3.3 based applications onto my hard disk
and setting up ProSEL menus to 'boot' them via the slinky card, but if
I went that far, I'd be too addicted to the slinky to ever remove it
from the system, and it gets mighty hot in there as it is :-)
So what you really need is a virtualization of a 5.25" disk that lives
on a ProDOS hard drive. RAM disk isn't much of a speed winner against
a hard drive, even with a Zip Chip.
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. ;-)
True, but to be honest I'm getting sick of keeping them around. They're
big, heavy, and blow up a lot. It'd be far easier to just avoid ever
having to keep them around, IMHO
I've had the opposite experience--I have only had three monitor (and TV)
problems in 25 years, and each time it was an incremental degradation in
an electrolytic capacitor--easily found and replaced.
I find the reliability of 1980s+ monitors excellent--particularly the
ones of Japanese origin.
There's no debating the big and heavy, though. ;-)
The way things are going, no one will be able to *afford* to dispose of
a CRT monitor in another decade--anyone attempting to get rid of one
will be prosecuted as an environmental terrorist!
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 *I* was building it, I'd adopt the OpenCores project's Wishbone Bus
http://www.opencores.org/projects.cgi/web/wishbone/wishbone
These guys have already amassed a phenomenal amount if IP, all there
for the using.
That approach illustrates the discipline required for a modular
design--good luck on recruiting Apple-oriented contributors, though.
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.
Sure. Although even if the excitement doesn't follow up, and all that
gets created is the means to easily recreate Apple II systems + some
nice to have peripherals I can live with the fact that there's
boundless untapped potential there.
Of course, things might never get that far, hence trying my level best
to push things that way using only my hands and a keyboard ;-)
Cool!
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.
No problems... I was just being facetious ;-)
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. ;-)
Indeed. although also every year the means to make such a thing a
reality gets that much closer, so the effort doesn't go totally to
waste.
I think that's debatable. If you look at what people were fantasizing
about six or seven years ago, there is very little cumulative progress
toward a result. And, I think, there is a potential downside if all the
fantasizing about the "perfect" detracts from individual contributors
going off and making "good" things that are real and very useful--like
CFFA cards.
Then, of course, there is the standard problem that if there are five
people discussing, there will be ten or more ideas of what "perfect" is.
;-)
-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."