At 04:34 PM 10/3/98 -0700, you wrote:
>
>I'm telling you, its the Y2K scare. You'll start to see more and more of
>this hardware become available as people start to panic.
I'm frightened to realize that you're serious. Great, let's start
scaring them even more, to increase our collections. :-)
- John
Surfing the back alleys of the Internet today, I found an ISP in Nova
Scotia that has downloads of Internet access and utilities software for
Commodores, Apple II's, and Atari's.
Cool.
Chebucto Net
http://ccn.cs.dal.ca
The download page is at http://ccn.cs.dal.ca/Services/PDA/PDA.html
--
Warbaby
The WebSite. The Domain. The Empire.
http://www.warbaby.com
The MonkeyPool
WebSite Content Development
http://www.monkeypool.com
Once you get the nose on, the rest is just makeup.
>> What you find "bizarre" is almost certainly what I like about them. 12-,
>> 13-, and 14-bit wide instruction words, Harvard architecture so that
>You've been using them for quite a while if you remember the 13-bit ones. :-)
>IIRC, that was the PIC1670 (not PIC16C70!); perhaps there were some other
>13-bitters. That was before I started with PICs, though I have the old data
>books around here somewhere.
I was using them when they weren't even called PIC's, and were sold
by General Instruments...
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology Voice: 301-767-5917
7328 Bradley Blvd Fax: 301-767-5927
Bethesda, MD, USA 20817
Some thoughts on this homebrew stuff...
Front Panels:
-------------
I've been mulling over the idea of building a "generic" front panel.
Clearly there is a lot of resonance with the blinking lights of the
PDP-series, the Altairs and IMSAIs etc. However if I did this it would have
to be both durable and cheap. Having rebuilt a couple of PDP-8 KC8's I
think the rocker over the slide switch can be cheap but it isn't durable.
I've been sketching ideas based on a rocker that is threaded on a rod. The
back of the rocker contains a 'paddle' which when the rocker is down,
breaks an IR/detector gap. This has a couple of benefits. One the rockers
are on a rod so they don't have small pins to break off, and two the switch
mechanism is optical and thus not subject to oxidation decay that
mechanical systems suffer. Of course I would like the front panel to be
usable for a variety of hardware designs and that leaves open the question
of 'generic' switches. Clearly there are the following switch requirements:
Run/Stop
Single Step - momentary
Deposit - momentary
Examine - momentary
Load Address - momentary
switch register - what size? Could have 8 to 32 bits if we wanted
Key switch - Off/On/Panel Lock
Some panels adopted a dual action switch for 'examine'/'examine next' and
'deposit'/'deposit next'. Clearly that's harder to do with my simple
optical switch.
Compound Computers
------------------
I've about half decided to build something PDP-8 like out of PIC chips.
They are relatively cheap, easy to program, and quite fast. I hadn't
thought about using them as base units (microcode sequencer, ALU control,
etc) until this discussion began, but it also raised the point of
'emulators' and I began to wonder what if you build a Z80 system that
emulated a PDP-8 with one of these custom front panels. That turns out to
be more of a software effort than a hardware effort.
Transistor based CPUs
----------------------
You can get PC boards made fairly cheaply, if you wanted to do a transistor
based CPU I would definitely consider having a few hundred 'flip chip'
equivalents made. It wouldn't have to be 1:1 DEC replacements but they
showed it could be done. Wiring up 12 flip flops by hand on a piece of perf
board (4 transistors each!) would be extremely painful.
TTL Logic based CPUs
--------------------
First, find a 50Amp 5 volt supply. :-) The thing about TTL logic that
always amazes me is how much power it draws. I built a digital PLL out of
TTL chips once (about 40 chips) it was easily drawing 3-4 amps at speed.
74HC logic might be a good compromise here.
The use of CRTs
---------------
There is a really clever homebrew display that was influenced by early
computers called the 'beer budget graphics display' and was featured in
BYTE magazine in the late 70's. Basically this was two R2R D/A ladders
driving the X/Y inputs to an oscilloscope. If you make a 12 bit machine you
could build a 4K x 4K resolution display fairly easily. (You will be core
limited in terms of points to plot but what the heck right?) This type of
output was featured in several different early computers.
Anyway, just some thoughts...
--Chuck
Does anyone know off-hand where there might be a complete, working PDP-10
system?
Sam Alternate e-mail: dastar(a)siconic.com
-------------------------------------------------------------------------------
Ever onward.
Coming in 1999: Vintage Computer Festival 3.0
See http://www.vintage.org/vcf for details!
[Last web site update: 09/21/98]
SUch crazy people.
I think I will re-organize the Governor William J. Le Petomane Gambling
Casino for the Insane
(formerly the La Petomane Asylum for the Insane) and re-open this
establishment as the
Governor William J. LaPetomaine Computer Store for the Insane!
A new era of lunacy is just on the horizon for the insane computer
collector . . . .
{Tongue removed from Cheek}
On Mon, 5 Oct 1998 11:04:41 -0700 (PDT) Cameron Kaiser
<ckaiser(a)oa.ptloma.edu> writes:
>::
>::Somebody's posted a Commodore C65 prototype on eBay. 4 days left
>and the
>::bidding is at $1025.
>::
>
>That's nothing. The last one sold went for $1400. (!)
>
>--
>-------------------------- personal page:
>http://calvin.ptloma.edu/~spectre/ --
>Cameron Kaiser Information Technology Services Database
>Programmer
>Point Loma Nazarene University Fax: +1 619
>849 2581
>ckaiser(a)ptloma.edu Phone: +1 619
>849 2539
>-- Jesus at a disco: "Help! I've risen and I can't get down!"
>-----------------
>
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At 09:24 AM 10/5/98 -0500, Kirk Scott wrote:
>
>
>On Sun, 4 Oct 1998, Phil Clayton wrote:
>
>> I'm sure I have read before that some users on the forum use internet
>> software for accessing the internet that will run on old XT running DOS
>> (Text only)..?
>> Would someone tell me where I could get a copy of this software..
>> Thanks..
>> Phil...
>
>Phil:
>
>The program you want is "Nettamer" and you can get it from garbo.uwasa.fi
>in the /pc/connect/ directory; filename: n1101xt.zip
>
>It's great, it was the first program I used to surf the 'Net on my XT!
>
>Kirk Scott
You might also want to check into something called Arachne. Although
it lists a 386 as a "minimum," the docs say it should run on any x86 with
an EGA or VGA card. BTW, Arachne is basically a graphical web browser
with (i think) ppp or slip buillt in. (Runs under DOS too)
Les
OK, next question. While I look for weird expansion cards, is there
any book that I stand a chance at finding which details the DOS flopy
format?
>> Hmmm... I don't know of one built commercially, but how about a board
>> based round an FPGA (for the non-hardware types, basically a
configurable
>> chip that you can make just about any logic circuit out of) linked to
an
>> floppy drive. Oh, and some kind of programmable clock (I don't think
>> dividing down a master clock with the FPGA would really do it)/PLL
thingy
>> to act as a read clock.
>
>Overly complicated, no (hardware) PLL necessary. Just sample the data
from
>the drive at a sufficient multiple of the channel code data rate (8x
should be
>plenty), and do the data separation in software. That way it really is
>completely independent of the data format. That's the way I designed
my
>closed-caption decoder (5x), and it works quite well.
>
>Note that this doesn't deal with all of the weird Apple ][ copy
protection
>schemes (like spiral tracks), but it will deal with some of them.
>
>I have a twiggy disks for the Lisa 1 with a bad sector. I've always
wondered
>whether hacking the drive electronics to allow software control over
the
>read amplifier gain and/or data slice threshold would let me recover
that
>sector.
>
>Cheers,
>Eric
>
>
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
My mailer crashed and I lost some addresses. A few days ago I asked if
anyone needed a 486DX/2 66 chip...uh...if you responded then, please email
me again. There were three responses, and I remember that the third one
was Uncle Rodger.
Sorry for the inconvenience, guys.
Aaron
Hi all,
I got a Plessey PDP-11 clone from John Lawson today and was just poking
around at the cards. I thought I'd check to see if anyone had any info on
some of the non-DEC stuff in there:
1. Peritek, video board, "VIURAM VRG-Q11" - there is a cable plugged into
the 10-pin connector on this one, which ends in a single BNC plug. What
kind of video does this output? Any ideas on what kind of display I could
use?
2. Plessey, memory, p/n M8044DK and p/n M 8044 DB
3. Plessey, multifunction p/n PM-MFV11A
4. Standard Memories, ???, MM-148 - this board has 4 rows of MCM6665 64k
rams and a toggle switch on the handle edge. There are two led's, one
labeled "PWR OFF" and one labeled "ON RUN." There is also an 8-position
DIP switch toward the connector side.
Thanks in advance,
Aaron
