Hi all,
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Regards
--
Kevan
Old Computer Collector: http://staff.motiv.co.uk/~kevan/
On Wed, 31 Dec 1969, Marvin wrote:
> I just plugged in the Epson PX-8 and the only thing that happens is the
> LCD screen turns on, but nothing else. I plugged in a power supply to
> charge the battery (and then checked the battery voltage) so that is not
> the problem. I also pressed both the outside reset switch with no
> response, and then pressed the "master" reset switch in the compartment
> on the bottom of the machine, again with no response. When the bottom
> was opened, there was space for two ROMs; the center one was empty and
> the one to the side had an Epson ROM of some sort installed. There was
Marvin, the socket labelled ROM1 should have an Epson ROM in it, and as
far as I know it is the O/S ROM. ROM2 socket on mine has Portable
WordStar and is not necessary to run the system as far as I know. In
fact, I just pulled the ROM on mine and the system still came up (BTW,
those ROMs are neat...they have a little plastic bucket that the ROM sits
in that makes it easy to pull them out and re-insert them). My battery
is worn and does not hold a charge anymore, but it will recharge and
operate for a little while (how long I don't know since I never have it
on for more than a few minutes) but as soon as I plug in the power supply
it works fine. Inside the ROM compartment you will notice an "Initial
Reset" button. Have you tried pressing that? There is also a dip switch
inside (SW4)...my settings are as follows:
1:ON
2:ON
3:ON
4:ON
5:OFF
6:ON
7:OFF
8:OFF
There is a smaller compartment on the bottom near that back of the
unit...did you make sure there is a ROM in there? Is it seated correctly?
Hope this helps in some small way.
Sam
-------------------------------------------------------------------------------
Computer Historian, Programmer, Musician, Philosopher, Athlete, Writer, Jackass
i believe it's a "dumb terminal" that uses NTSC video - probably emulates
either the H19 or VT100 (or both). i think the "save" button is used in
configuring (and saving) terminal options.
- glenn
At 04:00 PM 12/31/70 +0000, Marvin wrote:
>Among the things I picked up yesterday was a Zenith Data Systems
>keyboard, model ZTX-1-A. The top of the keyboard looks like a regular
>keyboard but the back has an RCA jack labeled "Video Output", a 40 pin
>header labeled "Printer", a pushbutton labeled "Save", a db9 male
>connector labeled "Power", two phone jacks labeled "Phone Connect" and
>"Wall Connect", and a switch near the phone jacks labeled
>"Multiline/Single Line". Anyone have any idea what this thing is?
>Thanks.
>
>
>
+=========================================================+
| Glenn F. Roberts, Falls Church, VA
| Comments are my own and not the opinion of my employer
| groberts(a)mitre.org
> On 21 Jul 97 at 10:15, Greg Mast wrote:
> > Apple III External Floppy Drive **PHOTO**
> I noticed the current bid for this was $103.50. I'd love to hear if
> you actually collect that much for it. I can't believe someone
> actually wants it THAT bad.
Me too. I figured $20-$30. But who am I to complain? But like they say,
talk is cheap. We'll see if they pull through. I had a Radio Shack hard
drive that was bid up to $150 a while back. Both high bidders flaked and
I relisted it and sold it for $30. Go figure.
On the other hand, I had a garage sale last weekend. Not one person
interested in the piles of Apple, Commodore, Atari stuff. I mean, if you
guys aren't going to garage sales to buy stuff, you're missing a lot of
deals. Most of the stuff at the Goodwill has an old garage sale sticker
on it.
> I.E Making a new ROM. Well, I do have the IBM PC manual that has the ROM
> unassembled in it... I thought those panels worked by playing with the
> lines on the CPU. Sounds like more work than I have time to do now. I do
> know that E11 lets you pull this off via the paralell port. It would be a
> neat trick, if I had time to work at it.
They do work by playing with the lines on the CPU. However, the 8088 (and
most microprocessors) do not allow you to get to the internal registers
>from the bus. It works on the PDP-11 because the registers have a bus
address; i.e., you can DMA into registers.
This stopped being possible on the microprocessor implementations of the
the PDP-11, which is where MicroODT fills in.
Roger ivie
ivie(a)cc.usu.edu
Quick question:
10base2 (cheapernet) thin coax eithernet: What is the minimum cable length?
Everything I have has the maximum and I remember there is a minimim.
Allison
Minimum is 1 meter, max is 185m 25ohm terminator at each in, 48 drops per
segment.
----------
> From: Allison J Parent <allisonp(a)world.std.com>
> To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
> Subject: 10base2
> Date: Monday, July 28, 1997 1:00 PM
>
> Quick question:
>
> 10base2 (cheapernet) thin coax eithernet: What is the minimum cable
length?
> Everything I have has the maximum and I remember there is a minimim.
>
> Allison
<but then again, I do have a PC-XT motherboard to waste... It would be
<interesting... Is it possible? It would score high on the nerdity
<scale...
The 8088 would be difficult to make a hardware style front pannel like the
PDP-8e or 11/70s had but a software front pannel is doable with a spare
parallel port or homebrew IO card. It would have to ahve some software to
dump registers to lights based on switchs, load registers from switches
(at least 16 of them for data/addresses) also other things like single
stepping and single instruction would have to be handled. The other
possibility is an embedded ODT like the 11/03, 11/23 or later q-bus PDP-11s
have. IT allows memory display, changing locations, halting, running from
an address and display/load registers from a terminal(console).
Allison
On Sun, 27 Jul 1997 14:13:00 -0500 (CDT), Brett <danjo(a)xnet.com> wrote:
>>Unless someone can verify the legal status of the copyrights on the ROMs.
>>I am a little busy setting up Rescue trips to dig much further into THAT
>>moras of mumbo-jumbo.
I got my copies of the ROM images off of ftp.funet.fi. It seems that this
Finland ftp site has boat loads of Commodore software, including the ROM
images to be used for emulators (I used mine for the PC-VIC emulator and as a
known-good ROM image to compare my Kernel assemblies with).
If my wife really understood what I was doing with the VIC Kernel project,
she'd probably say "Why??" too. But, it's really more of saying to myself that
I reverse-engineered object-code into a recompilable file and that I learned
something than anything else. Since I can't yet really own the source code, I
made my own <g>.
-------------------------------------------------
Rich Cini/WUGNET
e-mail: rcini(a)msn.com
- ClubWin Charter Member (6)
- MCPS Windows 95/Netowrking
