They are pretty machines, most definitely.
In the "odd PCs" department, I have to mention the Seequa
Chameleon. It has an 8088 and a Z80, so it can run DOS, CP/M-80, or
CP/M-86. A friend and mentor had one when I was in my teens
(mid-1980s) and I got to use it a fair bit. I really liked it. The
display (green) was bright and sharp, and the keyboard had a nice
feel. As a "luggable", the mechanical design was similar to that of
the Kaypro systems, but if memory serves, it was slightly smaller. A
good machine overall. I hope to have one here someday; that will
certainly bring back some memories.
-Dave
--
Dave McGuire
Port Charlotte, FL
I have one in excellent condition. Wanna make an offer?
SteveRob
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end
Hello cctalkers,
I'm trying to help someone recover data from an MFM drive in an old Pinnacle 1a system that had MirageOS installed. The system hasn't been booted in years and no longer boots to the hard disk. The drive spins up and sounds okay. We've tried to track down a copy of the MirageOS boot diskettes for the Pinnacle 1a system but haven't found any after looking for months.
It's time to come up with a "Plan B". Does anyone have a suggestion about how to read the "raw" data from the MFM hard disk? I was thinking about putting in into an older PC based system with an MFM controller and using some utilities to dump sectors to files that I could convert into something readable/usable. I haven't done this before so I'm hoping someone smarter has a 'cunning plan' of how to do this. I'm a programmer and don't mind write some utilities to pick apart the data after it's off the hard drive.
Any ideas are appreciated.
Thanks,
david.
daviderhart at oldzonian.com
daviderhart at sageandstride.orghttp://www.sageandstride.org
Sounds a little familiar...
---------- Forwarded Message ----------
> How many group members does it take to change a light bulb?
>
> One to change the light bulb and to post that the light bulb has been
> changed.
>
> Fourteen to share similar experiences of changing light bulbs and how the
> light bulb could have been changed differently.
>
> Seven to caution about the dangers of changing light bulbs.
>
> Seven more to point out spelling/grammar errors in posts about changing
> light bulbs.
>
> Three to correct spelling/grammar errors.
>
> Six to argue over whether it's "lightbulb" or "light bulb".
>
> Another six to condemn those six as stupid.
>
> Fifteen to claim experience in the lighting industry and give the correct
> spelling.
>
> Nineteen to post that this group is not about light bulbs and to please take
> this discussion to a light bulb (or light bulb) forum.
>
> Eleven to defend the posting to the group saying that we all use light bulbs
> and therefore the posts are relevant to this group.
>
> Thirty-six to debate which method of changing light bulbs is superior, where
> to buy the best light bulbs, what brand of light bulbs work best for this
> technique, and what brands are faulty.
>
> Seven to post URLs where one can see examples of different light bulbs.
>
> Four to post that the URLs were posted incorrectly and then post the
> corrected URL.
>
> Three to post about links they found from the URLs that are relevant to this
> group which makes light bulbs relevant to this group.
>
> Thirteen to link all posts to date, quote them in their entirety
> including all headers and signatures, and add "Me too".
>
> Five to post to the group that they will no longer post because they cannot
> handle the light bulb controversy.
>
> Four to say "Didn't we go through this already a short time ago?"
>
> Thirteen to say "Do a Google search on light bulbs before posting
> questions about light bulbs."
>
> Three to tell a funny story about their cat and a light bulb.
>
> - - - AND - - -
>
> One group lurker to respond to the original post 6 months from now
> with something unrelated and start it all over again
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
Someone in Austin has a largish collection of old 8bit Atari stuff for
sale. Price seems a bit steep to me, but then again maybe I don't
appreciate the Atari like I should :) Local pickup only.
http://austin.craigslist.org/sys/359890829.html
> all my disks (except the hard disk) are bad *snifful*.
Have you tried imagedisk and a 360K drive?
They are 400k (10 sector, 40trk)
I have some discs I can try imaging, though I haven't turned up
a set of base discs yet.
>
>Subject: Re: Most used toys, was Re: The late, great TRS-80
> From: "Ethan Dicks" <ethan.dicks at gmail.com>
> Date: Tue, 26 Jun 2007 16:47:18 -0400
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 6/26/07, Dave McGuire <mcguire at neurotica.com> wrote:
>> My most
>> used classic machine at the moment is a PDP-8/m; I've carved out a
>> permanent place for it on my desk. It contains an RX8E which is
>> connected to a arallel port adapter based on Chuck Dickman's design,
>> which is in turn connected to a small x86 SBC running Linux to give
>> the 8/m a disk subsystem.
>
>Interesting way to do it. How "based on" is it? I know of Chuck's
>parallel port adapter, but I'm curious how you've tweaked it.
I'm curious too.
>
>Is the SBC tucked into the /m or is it external? Does the SBC host
>your disk images locally, or over a network?
>
>Given that an RX8E is a PIO device, it makes me think that it wouldn't
>be that hard to come up with an OS/8 handler to treat the 12-bit-input
>and output ports on a DKC8AA as a disk interface to an external,
>modern machine. It doesn't help -8/e/f/m owners much, but the DKC8AA
>was a standard peripheral on the -8/a, and normally, unless one is
>using the output port as a printer port, unused.
I'm sure that will work, many of the OS/8 devices are simple enough
and the drivers are small. It would be a great way to get a "disk" on
my 8f.
Allison
>Much to think about there...
>
>-ethan
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290132606044&fromMakeTra…
comes with a box labelled *system software 3.n1*. I
previously thought mine had everything - a stack of
manuals probably 3' tall. Mine don't have that. And
all my disks (except the hard disk) are bad *snifful*.
I'm still looking for original images. I do have the media.
____________________________________________________________________________________
Pinpoint customers who are looking for what you sell.
http://searchmarketing.yahoo.com/
Just catching up, still about a dozen digests behind!
> What are the most bizarre, way-out or just plain *different* machines
> that folks have seen?
Well how about a machine with a normal instruction set but no program
counter?
It has a 48 bit word, and most instructions are 24 bits, with a few
48 bit ones.
It has three 'Control Registers', and normally at least one has a
unconditional absolute jump instruction in it, which jumps to the
next word.
After a single length instruction is executed, it gets one added to
it (in binary coded decimal), and it gets moved from control register
(CR) 1 to CR3. At the same time, CR3 goes to CR2 and CR2 goes to CR1
ready for execution.
If it is a jump instruction things are a bit different, the original
CR2 and CR3 are saved in the 'A' register and the value at the
address specified in the jump instruction gets put into CR1 and CR2
instead of the old values of CR2 and CR3. CR1 still gets incremented
and put in CR3.
Simple enough so far, but what about conditional jumps and procedure
calls?
On a condition jump where the condition is true, the top 8 bits of
the instruction get cleared, which makes it into an unconditional jump.
A procedure call (which can be conditional or unconditional) is just
a jump instruction. What makes it a procedure call is in the function
itself. It stores the A register in memory, usually at the word after
the end of the routine. When the program reaches it end, it executes
this word. If the procedure call was in the second (bottom) half of
the word, then it will execute a jump instruction to the word after
the word where the function call was made from. If the procedure call
was in the first (top) half of the word, then it will first execute
what had been in the second half of the word, which could itself be a
procedure call, which actually works out just fine if you think about
it.
Now I hear your objections - no recursion, no re-entrancy etc. But
this machine had no interrupts, and if you really needed recursion
then you could implement a stack in software and save the A-register
in that stack. Anyway, with a maximum of 2000 (yes 2000 not 2048)
words of store and overlays on drum backing store or magnetic tape,
programs could not be huge anyway.
Other weirdness: pound shillings and pence arithmetic in hardware
with a variable ten shillings position register, so than digits to
the left were decimal (radix 10), the addressed digit was radix 2,
the next digit was decimal, the next was radix 12 and the rest were
decimal. This even had a multiply instruction which could multiply a
LSD amount by a decimal amount. Division was all in software.
The machine was designed in the late 1950s, first delivered 1962
(such a long gestation that it was the only ICT/ICL machine where all
the promised applications software/libraries was ready before the
first machine shipped). It a collaboration between the British
Tabulating Machine company (which had recently given up its rights to
use all IBM designs and patents!) and the British General Electric
Company, Telephone division based in Coventry. By the time it
shipped, BTM had become ICT (International Computers and Tabulators)
and went on to be merged with almost all the other British computer
companies to become ICL (International Computers Ltd).
Somewhere between 155 and 200 of these ICT 1300 series machines were
made up to becoming obsolete in 1965. As I understand it, in 1965
there were 950 computers in Britain, so a large proportion were of
this type, though of course some were exported.
Another weird machine, the CHLL, Compacted High Level Language
computer. Executed Coral 66 (a real time variant of Algol 60) in
microcode. It was a 24 bit machine but instructions could be any
multiple of 3 bits, and could start on any 3 bit boundary. Top 21
bits of program counter were word address and the bottom 3 bits were
the 3 bit byte address within the word. The machine was flyable, but
otherwise a normal computer which could have a teletype, paper tape
reader and punch attached. Only two made (one ground prototype and
one flyable).
-----------------Original Message:
Date: Mon, 25 Jun 2007 21:15:11 -0700 (PDT)
From: steven stengel <tosteve at yahoo.com>
Subject: WANTED: TRS-80 video/disk interface <-> model 100 cable
I have the TRS-80 disk/video interface module, but not the cable to connect to my model 100.
Does anyone know how to make one?
Thanks-
Steve.
-----------------Reply:
It looks simple enough; just take a 40c IDE HD cable and crimp
a 40-pin DIP header on the end...
But there's a catch:
The connectors will not be offset the standard way relative to each
other, i.e. you need to swap the even and odd pins somehow.
There are two ways of doing that:
1 - Separate all the wires at one end and swap them when you
insert them in the connector; put the striped wire in the
second slot, the second in the first, the third in the fourth,
the fourth in the third, etc.
2 - Crimp the 40-pin DIP header on an IDE cable without swapping;
Get a second IDE cable and a set of 40 header pins such
as you would find on an old motherboard (make sure they're
long enough) and use them to connect the two cables; this
will give you the offset and also a way to connect and dis-
connect without opening the cover and possibly damaging
the delicate 40-pin DIP header. If you make the M100 cable
the right length you can fasten the header to the back of the
M100 with DS tape and effectively have the same setup as
the M102 & 200.
If, as usual, I haven't made it very clear, contact me off-list & I'll send
you some pictures.
BTW, if you're new to the M100 world, check out club100.org and the
user group there; lots of folks always willing to help.
mike
hi, i have a spectrum 128K +2 which has been put somewhere "safe" by my parents. When i used it and hit the reset key (by the joystick ports on the left side) i would sometimes end up a secret debug (?) menu. I never altered anything when it came up (a mate did and ruined his spectrum!) and simply pressed reset again. Im just curious to see if anyone knows how to make it appear on reset. What sort of things did it alter? - Andrew B (via mobile phone)
At 12:14 PM 6/25/2007, Liam Proven wrote:
>The real point is that the Windows "start button" is not analagous or
>homologous to a mechanical start button on an engine. You may as well
>compare a button on Windows to a button on your cardigan. They're both
>"buttons" but they have nothing in common.
Just to confuse matters, today's hybrid Toyota Prius does not
require the "key" in the "ignition" - it will start if it
detects the key in your pocket - and the "start" button
is up on the dash, a round button perhaps 1 1/2" in size,
with the circle-with-a-vertical-line icon on it. But it
won't start unless your foot is on the brake. Then you can
move the (clearly electronic) gear shift into forward or reverse.
There's a separate rectangular "Park" button. And when you pull
up to a stop light, you can feel the entire car shut down
except for the accessory power.
There's a central 4x6" video display, too. Shows a rear-view video
when you're in reverse, while you're driving it has all sorts of
MPG monitoring graphs and animated graphics.
- John
>
>Subject: Re: Inside old games machines, was: Re: Simulated CP/M-68K?
> From: "Ethan Dicks" <ethan.dicks at gmail.com>
> Date: Mon, 18 Jun 2007 08:29:55 -0400
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 6/18/07, Gordon JC Pearce <gordon at gjcp.net> wrote:
>> On Sun, 2007-06-17 at 18:10 -0300, Alexandre Souza wrote:
>>
>> > In arcade machines, this is already done in MAME. But it would be great
>> > for old computers and any kind of gear.
>>
>> Did any of the CPUs we know and love, like the PDP-11 CPUs, find their
>> way into commercial games machines?
>
>I would be interested to learn if this ever happened. As far as I can
>tell (hardly authoritative), the arcade industry bypassed the T-11,
>probably primarily due to cost and availability. The Z-80, 6502, and
>6809 were favorites in the 8-bit realm, but when they needed something
>with a bit more horsepower, I don't know what was common besides the
>68000 (as used in "Xenophobe", among others).
The T-11 offers PDP-11 archectecture but it's not very fast and not
much for availability outside DEC As other than the FALCON card or KXT-11.
If any of the pdp-11 machines made it to games I'd expect it would have
been a F11 (LSI-11/23) chipsets as they were faster and available before
the T-11.
>> I know a lot of the Atari vector
>> stuff had maths boxes based on AMD bit-slice parts.
>
>Yep. I helped a friend fix his Battlezone with a couple of 2901s I
>desoldered from a dead KA730 board.
>
>> It seems like the J11 processor would have been a good fit for some of
>> the more advanced games.
>
>Perhaps, but it wasn't a cheap chip. 20 years ago, I could afford
>used F-11-based gear (11/23, 11/24) because it ran around $300 for a
>barebones or lightly-loaded system (disks and controller extra, etc).
>I couldn't touch J-11 stuff because it was still in use commercially.
>
>In the mid-1980s, the 68000, then 68020 was just too cheap compared to
>the J-11, I'd estimate.
Same for the 6502/6581x series and they were fast enough for the price.
Games for the most part were judging from their construction a very
price sensitive product.
Did the RISC CPUs (arm, strongarm, and friends) make it in games?
Allison
It looks like Yahoo has found a new way of tracking people online,
I'd recommend going to the page for details on their "Web Beacons"
and to find a link to opt out. You apparently need to do this for
each browser you use.
http://info.yahoo.com/privacy/us/yahoo/webbeacons/details.html
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at aracnet.com (primary) | OpenVMS Enthusiast |
| MONK::HEALYZH (DECnet) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
I have the TRS-80 disk/video interface module, but not the cable to connect to my model 100.
Does anyone know how to make one?
Thanks-
Steve.
---------------------------------
Be a PS3 game guru.
Get your game face on with the latest PS3 news and previews at Yahoo! Games.
A while ago someone asked about early synthesizer-computer stuff. I
just saw this on Montreals Craigslist:
"Synth?tiseur ALHA SYNTAURI SYNTHESISER - $400"
http://montreal.craigslist.org/msg/359808712.html
I am not in any way affiliated with whoever this is. I'd buy it
myself if I had money, space and time (all in perpetual sparse
supply...) but i figured some here might be up for it.
Joe.
>I'm not a DJ, but I do play music and have collected it since I was a kid (many years ago).
>
>My 78rpm records (that I grew up listening to) are on mp3s on my laptop.
>My 33 1/3 rpm vinyl albums are on mp3s on my laptop.
>My 45 rpm records are on mp3s on my laptop.
>My cassette tapes are on mp3s on my laptop.
>My 8 track tapes are on mp3s on my laptop.
>My CDs are on mp3s on my laptop.
>and the mp3s that I downloaded from eMusic, WalMart, Apple, etc. are on my laptop.
I forgot to mention that some of my stuff is on YouTube too.
http://www.youtube.com/watch?v=qtWyNQDgtcA
Loaded from the same laptop that has my PDP-11 on it.
... and now I'm done with this topic since it's not really on topic.
Ashley
http://www.woffordwitch.comhttp://www.highlonesomeband.com
>Vinyl is dead. CDs are dying. Did anyone notice that the DJ at the
>wedding party next to the unofficial VCFeast Friday dinner was
>spinning mp3s? He was not ahead of his time. He is in it.
>
>I am not going to waste anymore time with this religious fight.
>
>--
>Will, the other radio DJ on this list.
I'm not a DJ, but I do play music and have collected it since I was a kid (many years ago).
My 78rpm records (that I grew up listening to) are on mp3s on my laptop.
My 33 1/3 rpm vinyl albums are on mp3s on my laptop.
My 45 rpm records are on mp3s on my laptop.
My cassette tapes are on mp3s on my laptop.
My 8 track tapes are on mp3s on my laptop.
My CDs are on mp3s on my laptop.
and the mp3s that I downloaded from eMusic, WalMart, Apple, etc. are on my laptop.
They are all also on my desktop system and my iPod.
And yes, those 78s do sound much better after you clean the noise up and turn them into mp3s.
My PDP-11 is also on my laptop, my desktop, and my web server, running in simh.
I had to throw that last line in there just to keep this thread on-topic. :-)
Ashley
http://www.woffordwitch.com
> Vinyl is dead. CDs are dying. Did anyone notice that the DJ at the
> wedding party next to the unofficial VCFeast Friday dinner was
> spinning mp3s? He was not ahead of his time. He is in it.
Exactly. Record companies are more than happy to sell you a $30
piece of plastic that can't be copied. There are niches, but this
ain't mainstream music distribution. "disappearance" wasn't the
right word, "irrelevance" was, going the way of 8-track tape and
Selectavision.
> I am not going to waste anymore time with this religious fight.
Neither am I
> The only thing *never* predicted
> was a small computer.
and the disappearance of the vinyl record.
record store scene in "A Clockwork Orange" for example.
Hi guys,
Progress is going a little slower than I'd hoped.. I've been roped into
working most of the past few weeks, so all I've got done is the final block
diagram and part of the schematic.
What I have got is a box containing ?200 worth of CPLDs, Molex connectors,
and other parts I had to order from Digikey. What this basically means is that
after I've got the schematic and PCB done, I can get a prototype built up
within a day or so of finishing the PCB. Assuming, that is, I manage to etch
the PCB without any bridged/broken tracks (especially on the CPLD and PIC,
which are both QFP parts).
So here's the final spec as I see it:
- USB interface -- USB2.0 Full Speed (12Mbit/sec)
- 40-pin disc interface connector. All outputs are open-collector -- the
first 34 pins are wired exactly as the standard PC floppy connector is. The
remaining 6 pins are all open-collector outputs with internal 680R pull-ups to
+5V. The state of these pins can also be read back in, assuming they're set to
'output high' mode.
- Replaceable bus drivers. 74LS07 O/C buffers are used - these are not
generally ESD sensitive, and are rated to 20V over the outputs. All the
buffers will be socketed and can be replaced easily in the field (as long as
you have spares, that is).
- Flexible triggering options:
- Start of capture:
- MFM sync word detection, with programmable sync word (*)
- Rising or falling edge of index pulse
- Hard-sector track mark detection
- "Wait for N start events before triggering" option
- Termination of capture:
- MFM sync word detection, with programmable sync word (*)
- Rising or falling edge of index pulse
- Hard-sector track mark detection
- "Wait for N start events before triggering" option
(*): The capture CPLD only has one MFM sync detector, which is shared between
the Start and Stop events. Note that the acquisition clock divider must be set
correctly in order for the sync word detector to function.
[ A future version of the CPLD may offer the option of independent clock
generators for the sync detector and acquisition system - currently Facq is
locked at 32 times the disc's bit-rate, e.g. 500kbit * 32 = 16MHz for 3.5-inch
HD. This is a fairly simple mod, so I might do it before release, but 32*Fdata
should be enough to get a usable scan ]
- 128 kilobytes onboard high-speed SRAM buffer with end-of-capture-address
storage.
- Disc writes controlled by a simple microsequencer - commands are:
- Wait N cycles and strobe WR_DATA
- Stop writing
- Open/close Write Gate
- Wait for hard-sector track mark
- Wait for N index pulses (where 1 <= N <= 31)
- Onboard flash upgrading feature for both the main microcontroller and
CPLD, with failed-flash recovery and forced-reflash options for both devices
(as long as the bootloader is still intact). The boot block will also be
protected against overwriting, to reduce the possibility of irrecoverable
'bricking'.
- Multi-platform (Linux and Windows initially, OSX if someone ports it)
programming library to handle disc read/write operations, including full
source code and example 'dartutil' application.
- Open-source hardware design, but with hardware available for purchase
either fully-assembled or as a complete or partial kit (optionally with SMD
parts soldered down).
- Power supply: USB bus power or external 7-12V power supply unit.
Can anyone think of anything else before I start drawing up the schematics?
I'm also thinking about an extension to the ImageDisk file format to allow
storage of raw MFM data, though I'm not sure how to go about doing this...
creating a whole new format may be a better idea.
So to recap, this is done:
- Block diagram and outline design
- CPLD code (all major functional units tested and working)
And this needs doing:
- Schematics
- PCB layout
- Prototyping
I'm currently toying with the idea of moving the half-done schematic from
OrCAD/SDT to KiCAD [<www.kicad-eda.org>] (on the basis that KiCAD is
open-source, newer, and can do just about everything OrCAD can do), though
I've not decided yet. Other suggestions (please don't suggest EAGLE...) will
be given due consideration :)
--
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