>From: "Ethan Dicks" <erd_6502(a)yahoo.com>
>
>--- "Dwight K. Elvey" <dwightk.elvey(a)amd.com> wrote:
>> Hi
>> An interesting side note. The power steering of your
>> auto is an example of an analog fluid amplifier.
>> Dwight
>
>I don't think _my_ auto (1968 Beetle) is an example of that. :-)
>
>-ethan
Hi
Actually, now that you mention it, my '68 Fiat 124 Spider
isn't either but it does have a vacuum booster on the master
cylender. I guess well have to buy newer examples of
analog amplifiers.
Dwight
I was collecting all of my hex LED displays into one place so I can
test them before embarking on a new 1802 project. I even dug into
my old box of spare Elf parts and pulled out a small board with four
TIL311 displays attached to a small microcontroller board - some kind
of monitor/indicator given to me by the brother of the guy that got
me into the 1802 as a kid.
He had given it to me to harvest the TIL displays. I finally *looked*
at the attached board to see what was on it - an NS 8073! I used to
have access to an RB5X robot when I was a volunteer at the local science
museum in High School - same chip - the hot-item-for-a-brief-moment
microcontroller with embedded Tiny Basic. Now, rather than harvest
the parts, I'm very tempted to reverse-engineer the schematic of the
little board to see what it does. Looks like there's a small bipolar
PROM, a 6116 SRAM, one or two TTL chips, and the TIL311s driven by
the output pins of the 8073. The whole thing is only a few square
inches.
The funny thing is that I'd recently picked up a few 8073s from ePay
to play with. I was planning on hooking them up to some 8031-based
8-line LCD displays I got for a few bucks each (originally out of
some flavor of AT&T office phone, IIRC). Sort of the Classic
Attraction principle in reverse - new toys attracting alike items
>from the recesses of the junk box rather than the normal way 'round.
Has anyone else played with the 8073 (in an RB5X or not)? If
they hadn't been so pricey 20 years ago, I might have gotten one
to experiment with back then.
-ethan
The New Yahoo! Search - Faster. Easier. Bingo.
http://search.yahoo.com
Ethan wrote:
> How does a resistive sheet computer work?
I wrote:
> Resistive sheets belong to a category of analog
> computing called network analyzers.
Oops, I need to correct this.
Resistive sheets belong to a category of analog
computing called passive element computers in which
network analyzers are probably the biggest and most
well known examples. But it also includes
* conductive sheets
* electrolytic tanks - create 3 dimensional simulations
* resistor networks
* pin and rod systems
* resistor and capacitor network
Passive element computers normally models a
physical system using only passive R-L-C components,
and solve equations in which dimensions in space
are the independent variables, rather than time.
Applications for passive element computers include
things like the simulation of
* reception patterns of a receiving antenna
* temperture, and pressure flow in a nozzle
* diffusion of material at a transistor junction
Here is an example:
You solder together a large two dimensional matrix
of resistors (all the same value). At each node where
the resistors are soldered together you solder a capacitor
connected to ground.
You then apply a voltage to one corner of this
resistor and capacitor network. As the current flows
through the network it begins to charge the capacitors.
You now have a computer that simulates the heat flow
across a metal plate the size of your matrix, both
over distance and over time. Without the capacitors
you are simulating only over distance.
A resistive sheet is a resistor matrix with a very
fine mesh. The finer the mesh, the better the simulation.
"Rubber-sheet computers have been used extensively
to study the trajectories of electrons and gas ions
in vacuum and gas tubes"
-Doug
=========================================
Doug Coward
@ home in Poulsbo, WA
Analog Computer Online Museum and History Center
http://dcoward.best.vwh.net/analog
=========================================
Hi All,
Looks as though the CS80 / LIF part of my HPIB disk reader/writer is working
OK now - thanks to those who gave me pointers.
I've come across another HPIB hard disk that that uses the Amigo command set
(- I think) and contains data in HFS format.
Does anyone have full documentation for these two standards in .pdf format?
Cheers
Peter Brown
_________________________________________________________________
On the move? Get Hotmail on your mobile phone http://www.msn.co.uk/mobile
I have a fair quantity of the following:
P21256-12
MCM6256BP12
Lh21256-12
MTC4c1024-8
KM41C1000BP-8
thanks Norm
snip:
>Date: Tue, 29 Apr 2003 11:37:28 -0700
>To: classiccmp(a)classiccmp.org
>From: Geoff Reed <geoffr(a)zipcon.net>
>Subject: 256x4 80NS or faster
>Reply-To: cctalk(a)classiccmp.org
>anyone have any of these floating around? I can't believe I gave 'em all
>away and now I need to populate a laserjet IIID memory board :(
Ethan wrote:
> How does a resistive sheet computer work?
Just a quick note for now.
Resistive sheets belong to a category of analog
computing called network analyzers.
> In the same vein (pun intended)... how would fluidic computers
> stack up? Digital? Analog? Mixed?
Fluidics (or fluid logic) can have both analog
and digital processes. You can perform boolean
operations, but you also can have fluid amplifers.
--Doug
=========================================
Doug Coward
@ home in Poulsbo, WA
Analog Computer Online Museum and History Center
http://dcoward.best.vwh.net/analog
=========================================
The Design Fort DTP wrote:
> I would be interested to learn more about the Heathkit EC-1
> analog computer. So far I only found pictures and specifications
> on the net. Is there a website that actually explained how
> this machine worked and/or what it could/can do.
> Even more are there informations about "programs" that this
> machine could run?
Most computer applications are simulations of one
kind or another, word processors, spreadsheets, drawing
programs, even a desktop GUI. Analog computers are the
masters of the art of simulation, but they are not used
for mundane simulations like these.
Analog Computers run mathematical simulation of physical
systems. Everything from the decay of subatomic particles
to the interaction of two colliding galaxies.
Do you want to:
* See the results of a chemical reaction?
* Test the design of an automobile tire?
* Study the effects of pollution on a fish population?
* Model blood flow through an organ?
* Understand the effects of lowering the interest rate?
* Fine tune the design of the Space Shuttle main engine?
* Control flooding on a major river?
* Explore new types of music?
All of these are physical systems governed by mathematical
equations.
Analog computers are PURELY parallel and can run programs
slower than real time, real time or faster than real time.
Simulations can be halted at any point and all aspects of
the simulation can be examined. Changes can then be made
and the simulation can then be continued from the point it
was halted or restart from the beginning. So, analog computers
can not only simulate a fixed systems, but can also test
'what if' cases very easily.
Analog computers can be a hardwired special purpose type or
flexible general purpose type.
The EC-1 with only nine amplifiers can be limiting in the
size of simulations it will handle. But analog computers
don't have the compatibility and the connectivity problem
of digital computers. Ten EC-1s could be connected together
to form an EC-1 with 90 amplifiers. The only problem would
be if more than 9 integrators were used then a slight
modification would have to be made to each EC-1 using an
integrator to allow one EC-1 to control the mode.
An EC-1 can also be directly connected to another brand
of analog computer. No problem other than the mode control
of integrators.
The lure of the EC-1 is that it a inexpensive and compact
example of vacuum tube computing.
The world is analog. The human mind is analog.
Digital computers make a nice hobby, and work just fine for
tasks composed of sequential steps, but they are just an
over hyped fad.
--Doug
=========================================
Doug Coward
@ home in Poulsbo, WA
Analog Computer Online Museum and History Center
http://dcoward.best.vwh.net/analog
=========================================
>From: "Don Maslin" <donm(a)cts.com>
>
>On Tue, 29 Apr 2003, Dwight K. Elvey wrote:
>
>> Hi
>> I've been looking at a pile of disk that I'd
>> collected over a period of years. Most are the
>> typical 10 hard sectored disk, formatted in the
>> same way as HDOS uses. In the pile, I found a
>> few that are marked "format 96". These have the
>> 10 plus index holes but they don't seem to be
>> the normal format. When I attempt to read them,
>> I can only read the first sector. All of the rest
>> don't seem to read. Does anyone know what this
>> was all about?
>> Dwight
>
>Dwight, I would assume that they were done on a 96tpi
>floppy drive.
> - don
>
Hi Don
That is what I figured. I've been working on my serial
bootstrap and transfer program. I'm able to read and
write an image to the H89 but I'm still having issues
getting the formatting to work. I copied some old
code that I have in the Fig-Forth that I did but it
is still missing something. I even went back and ran
the Forth FORMAT and it works fine. I suspect there is
some other initialization that I'm missing. I looked at
one stretch of code and there is an operation that should
always hang. Can't figure why the original works. It
may be something connected to the timer interrupt that
isn't normally there. I wish I'd made good notes when
I did the original but this was one of my first computer
projects, after working on my Poly88, and brain rot
is now catching up with me.
Once I get the format working, I can work on cleaning
up the user interface. Looking at the 96 stuff is a
little later on the list.
Dwight
Oops!
Got to look at where I send things.
Dwight
>From: "Dwight K. Elvey" <dwightk.elvey(a)amd.com>
>
>Hi Jim
> I would be interested in the H11 system, H-10 punch
>and especially the Poly 8813. I was at the VCF when the
>smoke came out. I loved it. Sellam had put my talk
>at an overlapped time with your event so I only saw
>the first part. I have a Poly 88 but have been looking
>for a 8813 for some time.
>Dwight
>
---snip---
