home .. forth .. misc mail list archive ..

never enough


Hi MISC readers,

Wayne Morellini wrote:

> Well I have to hand it to Dr Ting he is comming through, good on him! I
> actualy suggested to Chuck that a 24-bit design was better than a 20-bit
> design in 1988.

Well the reason for our doing 20 bit vs 24 or 32 bit was the number of
pins
as I have said many times.  Adding an extra pin would have cost me
an extra $40,000 or $50,000.  It is easy to say that a 24 bit chip
would be a better choice than a 20 bit chip but it only makes sense
if you assume that an extra $40,000 doesn't matter.  Maybe you have
a few hundred thousand extra disposable dollars sitting around, I
didn't. 

But we have heard many times that 32 bit chips are fashionable and
that no one except a few DSP designs use 20 or 24 bits.  But these
folks often miss the fact that we are not Intel, DEC, TI, or Motorola.
If you work on that scale then let me know if you need someone to 
work for you.
 
> Using programmable silicon designs that could be converted
> to mass production in 1996, and a cheap 160*160 screened PDA, with low end
> and powered processor, with simple Organiser functions would actually work
> (when they said it wouldn't) around 94-96.  Three good ideas in 12 years is
> ok.
 
I still consider going to FPGA a step backwards.  Chuck decided to go
from PGA to custom silicon in 1989 to get an order of magnitude or
two speedup and two orders of magnitude improvement in production
cost.  This is a 1000/1 or 10,000/1 ratio in price performance.
It is a very big hit to take.  The only justification that I can
see would be not having enough money for custom which is more
expensive.  But the 1,000/1 or 10,000/1 ratio is hard to ignore.

Ting is working with a company that can afford million gate
$10,000 FPGA for experiments but they make you realize the real 
value of being able to do production for under $1 as well as
being able to run ten times faster. This is still a long ways 
away from the billion gate designs that you suggest.

> But I have oftened toyed with the idea of hooking a 32 bit misc up to one of
> the portable Graphic/3D processor with on chip memory (upto 32 MB on chip
> now, I think).  Would certainly give enough memory for the program and the
> graphics.  How possible would this be?
 
It is completely possible, but not with programmable hardware as far as
I can see.  A memory bit requres 1+ transistor for DRAM and 4 to 6 for
SRAM.  32MB is 256 mega bits, and that could be 1.5 billion transistors!
There are no FPGA with 1.5 billion gates.   If a million gate FPGA costs
$10K would a billion gate FPGA cost $10M?

It would be possible for custom.  Costs are generally speaking
proportional 
to transistor count although since you are talking about up to 1.5
billion 
transistors in a somewhat regular grid the development cost would be
somewhat
lower.  But then again those memory designs ususally require more exotic
fab
processors such a vertical transistors.  Prototype fabs don't usually
offer
that stuff so you might have to purchase your own fab, not a big expense
for you.  As a rule of thumb $5 per transistor, so it is entirely
possible as long as you have about 8 billion dollars in your
budget.  That would put you on a scale with Intel, DEC and
others who spend that kind of money on developing the biggest
designs around.  I guess you have deeper pockets than I realized.
I thought $100,000 was a lot of money and that $1,000,000 would
be in another league but $8,000,000,000.00 is really in
another ball park all together.
 
To tell the truth, if I had 8 billion to invest it would be a
quite different picture.  I might not even bother with silicon
if I had that kind of development funds to manage. I would be
inclined to leapfrog to a pure optical 3D packaging design
to make things 1M times faster and put 1K more nodes in the
same space.
 
But even with silicon I think there is still the ratio of the
number of transistors in the processor to the number of transistors
in memory.  Now you are talkinga about a CPU and a 3D processor
to be mated to lots of memory.  When you start talking about 32MB
of memory you are talking about enough silicon that a fairly large
CPU is normally justified.
 
The idea of the F21 design is to get a few hundred mips per megaword
of memory or per 32K words or memory depending on the configuration
of nodes.  So for 32MB of memory you might get a few hundred billion 
instructions per second.  To attach that much memory to one CPU looks 
like a bottleneck from our standpoint but if all you want is to 
control a 3D chip...
 
We are currently (in one project) looking at reducing the design by
making I/O register based (no mems) and integrating a small amount
of memory on chip and multiple nodes connected together on a chip.
With wafer scale integration it looks like the upper limit is
somewhere around 15 million Forth mips from a "chip" in production
silicon today.  Of course I personally don't have the money to
do the design so "feasability" depends entirely on finding
the money like most other things.
 
> I actually was meaning to send you some names of new video compression stuff
> so that you could put the lot on one DVD, or send it over the net.
 
People have suggest that I need a new camcorder as my old one has worn
out from making tapes and copies.  People have suggested that I need to
buy newer and better compression equipment.  People have suggest that
I need to upgrade my website and pay ten times as much for a site
that can hold gigabytes and provide more streaming video bandwidth
for users.  These are all nice ideas.  But who is paying for it?
 
> I have
> heard of a few groups offering upto around 1000:1 compression ration (one
> video over a 33.6 kb/s modem with sound, then the Israelies announced they
> had been secretly using a 600:1 military method for years).  The only one I
> can remember is Adam's Platform in Australia.  Wavelets (being brought into
> jpeg/mpeg standards) and Mpeg 4 (DVD onto a CD-R) are available and not too
> far beind in the compression rate.
 
I did a lot of studying of compression techniques in college but things
were still primitive in the sixties. ;-)  One of the teams interested in
the
MISC multiprocessors are interested in compression/decompression and
have the best software out there at the moment.
 
As for consumer grade stuff, yes I could use a new computer, a DVD-
writer, new video equipment, new digitizing equipment, as well
as a working car and money to pay for rent and food.  I'll do what
I can but I am operating on a very restricted budget.
 
Jeff Fox