Is there a schematic for the H7441 regulator anywhere? There are several
out there for the H744 but, although they are plug compatible, the H7441 is
totally different. The H744 uses an LM723, but in the 7441 DEC appears to
have rolled their own regulator using a bunch discrete parts and opamps.
Bob
We use groups,io for the tom swift discussion group real handy to post photos, files and etc..
On Wednesday, June 17, 2020 Chris Hanson via cctalk <cmhanson at eschatologist.net; cctalk at classiccmp.org> wrote:
On Jun 17, 2020, at 1:50 AM, Tor Arntsen via cctalk <cctalk at classiccmp.org> wrote:
>
>>>> There is also groups.io, and it has some very nice features compared to
>
> Please please, no groups of any kinds. They're all horrible to use.
Do you mean "web forum" where you say "groups?"
> A
> genuine mailing list like this is infinitively easier to keep track of
> and read at leisure. Can't stand groups.io.
I've found the groups.io <http://groups.io/> mailing list mode to be perfectly reasonable for a number of groups I'm a part of. And it has a forum-like front end for people who insist on doing everything through a web page.
? -- Chris
Guys,
I have acquired this board and have trouble assigning it to a particular
computer manufacturer and type:
https://lh3.googleusercontent.com/byRPH3wCR2aqxGX9U8BZfFTT_XtF7QCKSyVXoNmGIk
UheiJ5BWqxYaCWdEshppLGYkOqUD7fl9XNeVzO_tDRKVOtbC3Js7T-pOvNUHs9MY9A36fc7dU6ro
1i7hx9Uhcfc6ukEGIdC5Ac6aTQhEFFoeWBxiI6Z24hZdvq1r6vRb4o-Lj778Wbo15hwxu0JxMuxE
tcopNv0FG0_g6nUv0Eofalqu4TmgPfUWVCd4Y4LdA0pnhDRMYF5c2ASzS00TsyukCVrUyr298tjo
vztVzUGEPHNL1beVCriuQIBLITaEMX3N8EBDuxpfav0vHFuyy9yfAgUI4uJB9qT6aFGEk2KplIVt
yNWZf9phTdj-jLtqns9WvdA9Ur2klrk4uPzMyWg6SKTKRlpMrvbJuMnqZodzxPFPvWCG5--kVVBD
KRAXW8xOTOPyxXx0xrcPifO49ni2SFYIkZgTb9d4gzvJaM8ugEb-jqHlc7uqHz5glwe4PfoN838w
zMozr43veZSNHRTm9IMfON-w7xvbVufJpa_MzhuaTlKf9pvVcRIuxfhG4pMeVq7K6phhHpsKPfG5
h4BRgDSimCE8mToI35IWS3Ty8j01-6bibKH_kB-t35aIdkv7JIC-YZ1sDoguSdyk8h1xbM2d9i_U
LFQYVC0oCHESgEGdqzGO3ntgwmV4khjgaQkcp2Bk-TuC7Nwrl57JI=w654-h871-no?authuser=
0
https://lh3.googleusercontent.com/HvltevPwIvyJF0qiAJR6wCAkI4lHfFGL2Gos5uoT4a
qEJNFBAwJ3m6XX8E6k0m515EYgZJMaCwFGXiGiTCkxDeT396EjsbkukK3_XYqNDjfU8o3Pbtdq8z
vm_q7MXShANXVFUL2wjXEbAhvBug1h42tZnxpDaxTCeNIHjqF2bgs6J_S3wCjmx538E4AuHCHxrr
CqIr8yvL7AGlZXCWe8u05YNNZbIrUCYHbTtxh15hc0SwfRPzQ2U2v-pPxHs7-rx5mPpwxovbp24a
CdwLBf5RRvvEZWZgyDGKG8xdF-al4kQdZMgxrVVXFMse3ee_J-QaYgALUxckGeWp2QxM4wolrd8Q
Y1PqaMaTgbws5WSrOeBBBZrhmrUeL4TzZAlCA4-FqtRpoPIA339y9JRixB8Q6LlUeNsWzlqGqkvC
JSCHlh_hpCXgwemhOtF4B1CLvNGs-PSZjTsnj_KOeSgeINz5Sc6TCrHmnxCcIY6D42aKMJRHZ9I9
7Z02FLsKwN6IKLxjifZvrkmEX4L8qXLbd8cuF0uf1PMjwC9WNC1_QpOmMiJOrBloG9pdrHRGvmfR
RPQE7c6_HxVklEpIbxqkLmQVkKF-oM8VYS3A11tvslxiZUcvQcEhuEYhPLoqTD8PDikYhxKyVLhq
S0DC-bIVBDDLeqiegQelHFjhptKwgs-0Q5mMrxvE6rdsd6-ipEf5Q=w654-h871-no?authuser=
0
Smells of (early) 1960s transistorized.
No helpful marking apart from
* "GATE JJ01" on SIDE A. (components).
* "C NT OL DATA" on side B (solder traces).
Big transistors are Motorola "180376008". Also, any ideas what the "246 636
B" boxes are, they have four legs?
Can any of you of mature years suggest anything?
Many thanks,
peter
|| | | | | | | | |
Peter Van Peborgh
62 St Mary's Rise
Writhlington Radstock
Somerset BA3 3PD
UK
01761 439 234
"Our times are in God's wise and loving hands"
|| | | | | | | | |
Not exactly on subject, but problems designing the IBM 604 Electronic Calculating Punch due to the use of existing vacuum tube designs is discussed in section 2.4 of:
Charles J. Bashe, Lyle R. Johnson, John H. Palmer, and Emerson W. Pugh
IBM?s Early Computers
The MIT Press, 1986
The book says Ralph Palmer set up a vacuum tube laboratory with the ability to manufacture small quantities of tubes. This helped them get credibility when they went to a vacuum tube manufacturer with a request for a design change to achieve the needed reliability for digital applications.
Hi!
Anyone else getting duplicate messages from this list? I get 2 copies of
most (but not all) messages, with the second copy often arriving
significantly later.
Julf
Hi all.
I recently bought a mystery blinkenlight panel. Closer inspection reveals it was manufactured by Intel in the early 70?s (1973), and some people on the book of faces suggested it was part of a ?device multiplexer?(?)
I?m 95% confident it?s not strictly a ?computer? blinkenlight panel, but rather an attached device, but that still hasn?t helped me narrow down what exactly it was from.
I?ve not seen any early Intel stuff as rack-mount, so i?m wondering if it was a prototype, or maybe a piece of internal/non-commercial hardware for Intel's own use.
I?m hoping someone here might be able to shed some light on this mystery.
Pictures: https://imgur.com/gallery/lD74oSy <https://imgur.com/gallery/lD74oSy>
Thanks in advance.
Josh Rice
Is there anyone that has already built a tool to dump TU58-tapes on a Linux
machine? I have the drive of course.
There is PUTR. But it is DOS only and is written in assembler so it cannot
be ported easily. The other option is running RT11 on a PDP-11, but then
there is the hassle of getting the dumps off the RT11 file system.
It is probably not too difficult to use relevant parts of the various TU58
Unix implementations out there to do something quickly, but if someone has
already done it, it would be great to not reinvent the wheel.
I have approximately 80 11/730 and 11/750 console and diag tapes that
need reading.
/Mattis
Folks,
I think I now have too many 3174 controllers. I have
1 x Rack Mount - Token Ring Card + MFM Disk Emulator
1 x Large Tabletop - Token Card
1 x Large Tabletop - Ethernet Card <=> I am keeping this.
1 x Small Tabletop - Token Ring card but won't run TCPIP code.
If anyone wants one of these I am happy to ship at cost but they are
220/240v and heavy so shipping to USA may be a problem.
I have a selection of floppy drives that can be fitted but I recommend using
a Gotek with FlashFloppy firmware.
I also have the following spares:-
1. working PSU for rack mount
2. non-working PSU for the rackmount systems but I am sure it can be
fixed
3. spare motherboard for rackmount
4. spare token ring card (if I can find it)
5. (I may have memory modules but can't remember where I put them
6. I think I have a 3299 multiplexor some where
Feel free to e-mail off-list with questions.
Dave Wade
G4UGM & EA7KAE
> With Jay retiring, what are the hosting plans for these mailing lists?
Hi Al,
I didn't know about Jay retiring or what that means for the list - i.e. does it need to find new infrastructure, new administraton/management, or both? I'm a relatively background person in the vintage computing scheme of things but I do have an involvement in the data centre / hosting area & so if no better options were to come forward would be very happy to pitch in somehow.
Don't know if anybody much cares, but:
The HDL synthesis aspect of the SMS data gathering / HDL synthesis
application is coming along. I can now handle:
- Oscillators (using a counter divider)
- Delay lines (using a shift register, so limited to a reasonable number
of FPGA clock clock cycles, so, say 200 ns is not unreasonable (20 bit
shift register at 100 MHz).
- Recognition and consolidation of individual signals into a "bus" when
generating groups corresponding to a group of individual ALD sheets.
(The individual ALD sheets use the individual signal names as they
appear on the sheet). A simple database table associates a given
individual signal with a bus, and identifies the bit in the bus that
corresponds to the individual signal.
So, I have not generated the IBM 1410 main oscillator, its main logic
clock and its I Ring - used to control instruction decode. I have
synthesized the logic clock into an FPGA and run it (with a slowed down
1410 oscillator so I could see what was going on.)
Also, a word about VHDL - and the Xilinx Vivado. While GHDL is useful,
I have found that Vivado is not slow at editing and *simulation*. Silly
me - I got in the habit of synthesizing stuff before I tested it under
simulation - partly because I didn't know any better at first. Vivado's
waveform viewer has some advantages (and disadvantages) compared to what
is available for GHDL.
I have also started exploring a piece of "intellectual property" I can
use - MicroBlaze - to allow my generated system to talk to my PC, via
TCP, for things like lights and switches. (Kind of like how the Amdahl
machines used to use first DG Novas, and later little UNIX systems for
their consoles, giving them access to the internals of the machine.)
I knew MicroBlaze existed, but now I have actually played with it a bit
-- still learning.
https://en.wikipedia.org/wiki/MicroBlaze
OK. the keyboard is working properly as far as I can tell, data is going
in and out, and I even swapped it for the keyboard on my VT220 and the
same symptoms persisted.
I just verified all four ROMs on the T11, and the ROM for the 8085,
against the images I found on the MAME site. So far so good.
One interesting finding - two of the lines (DAL3 and DAL1) on the T11 do
change states several times, but once the self-test has crashed, they
stay high with almost one volt of "wiggle". All the other data/address
lines are either high, low or switching between a good 1 and 0.
There are several places that the bus connects, including the ROMs,
1-bit dynamic RAMs and various octal latches & bidirectional buffers. I
connected a 10 ma VOM between each line and ground (to make sure a
low-resistance path (such as in the 'LS245 at E55) wasn't forcing it
high somehow.
All of the DAL15-0 lines requires more than 1.9 ma to bring it to ground
(well, 50 mv burden at 250 mv full scale, anyway).
That leaves the unlikely possibility that one of the octal TTL devices,
or ROMs. has developed a weird internal pathway that only interferes
with DAL3 & 1 on some bit patterns, but not all the time. Seems like a
zebra rather than a horse. The only part that drives multiple low-order
DAL lines at once besides the E19-22 ROMs is the E55 LS245.
The T11 spec sheet says that a good logic 0 (<0.4 volt) should be
possible with up to 3.2 ma sink... So I suspect the T11 has a couple of
bad output pull-down transistors on those lines. Anyone got a spare T11
chip I can buy or borrow? Or send you mine to plug into your board and
see if it fails the same way? :)
thanks.
Add on? solid state memory unit? some semi companies made tjem. For add to Dec and dg?? Dunno. A guess
....?? ed smecc
On Sunday, June 14, 2020 Joshua Rice via cctalk <Rice43 at btinternet.com; cctalk at classiccmp.org> wrote:
Hi all.
I recently bought a mystery blinkenlight panel. Closer inspection reveals it was manufactured by Intel in the early 70?s (1973), and some people on the book of faces suggested it was part of a ?device multiplexer?(?)
I?m 95% confident it?s not strictly a ?computer? blinkenlight panel, but rather an attached device, but that still hasn?t helped me narrow down what exactly it was from.
I?ve not seen any early Intel stuff as rack-mount, so i?m wondering if it was a prototype, or maybe a piece of internal/non-commercial hardware for Intel's own use.
I?m hoping someone here might be able to shed some light on this mystery.
Pictures: https://imgur.com/gallery/lD74oSy <https://imgur.com/gallery/lD74oSy>
Thanks in advance.
Josh Rice
I am getting closer to retirement (although not close enough) and I'm
considering selling off my PDP stuff, especially if I downsize and move.
Everything's working, but I just no longer DO anything with either
system... the adventure was acquiring all the pieces, fixing them and
learning the software :)
Anyhow I have an 8/A with cloned Programmer's Panel (Vince Slyngstad and
I made it around 2006) and limited function panel, 32K RAM board (also
have core), Philipp Hachtmann's USB interface board, RX01 floppy, two
RL02's, and a high-speed (optical) reel-to-reel paper tape reader. OS/8
is up and running. Several spare RL02 packs. It's all in a tall DEC rack
with an H-(something) power control box. The ASR-33 is not included, I'm
keeping that.
Also an 11/23+ (11/03 chassis) in a corporate cabinet with two RL02's, a
16-line serial interface, VT-220 terminal. Also an RQDX3 which is
connected to a loose 3.5" TEAC floppy drive. Have RT-11XM, RT-11SJ and
TSX-Plus 6.50 (all 16 timesharing ports are working too).
So, I am wondering if there's any market for them (preferably as
complete systems). Shipping would be difficult due to the size/weight
(I'm in rural south central Missouri). I'm not looking to give them
away, or to part out, but would entertain reasonable package deals
rather than deal with the "LQQK! RARE!!" bull on ebay.
I can send pics to interested parties. Let me know,
thanks!
Charles
I have a bunch of Power7 720's I would like to get running, and I'm have a
tough time tracking down any VIOS newer than 2.1. Does someone here have
some 2.2.6 or later CD's they would like to sell me?
Thanks!
--
Hi all --
I'm working on a PDP-8/A I picked up at VCF West last summer. After a lot
of cleaning and some power supply repair it's showing signs of life (CPU
seems to be at least minimally functional, core memory is going to need
some debugging.)
The transformer in the power supply is humming quite loudly, however, and
I'm curious if this is normal for the 8/A (or is typical for an 8/A of this
vintage). I'm used to the supplies in various other DEC machines not being
exactly silent but this is a rather severe 60Hz buzz that you can clearly
hear over the fans when the machine is in operation.
Thanks,
Josh
Hello,
I'm looking for Cobalt Qube cases, preferably in North America.
I would prefer non working Qubes as I don't want to deprive anyone of
working ones. Doesn't matter whether it's a 1, 2 or 3. I'm looking to
repurpose the cases.
Thanks!
> Is there anyone that has already built a tool to dump TU58-tapes on a Linux
> machine? I have the drive of course.
>
> There is PUTR. But it is DOS only and is written in assembler so it cannot
> be ported easily. The other option is running RT11 on a PDP-11, but then
> there is the hassle of getting the dumps off the RT11 file system.
>
>
> It is probably not too difficult to use relevant parts of the various TU58
> Unix implementations out there to do something quickly, but if someone has
> already done it, it would be great to not reinvent the wheel.
>
> I have approximately 80 11/730 and 11/750 console and diag tapes that
> need reading.
Just a thought - if the TU58 connects via serial, then what about running
SIMH and giving it a serial device which is connected to the TU58? That
could fix both problems - how to talk to the device, and how to deal with
the data on the tapes.
John
Liam Proven wrote:
> I don't know. There is a huge amount of tradition and culture in
> computing now, and as a result, few people seem to have informed,
> relatively unbiased opinions. There hasn't been much real diversity in
> decades.
>
> 25 or 30y ago, people discussed the merits of Smalltalk or Prolog or
> Forth; now most people have never seen or heard of them, and it's just
> which curly-bracket language you favour, or does your preferred
> language run in a VM or is it compiled to a native binary.
Agreed. While I'm much more favorably disposed towards C than you are,
the increasing homogeneity of almost all modern languages is
discouraging and, I think, detrimental to the field as a whole. Forth
and Smalltalk alike were eye-openers when I discovered them (and
Smalltalk in particular was a breath of fresh air, after I'd spent
years failing to ever really grok OOP with the likes of C++ and Java,)
because both presented genuinely *different* and beautifully
consistent ways to think about structuring and specifying a computer
program. These days, though, outside of deliberately jokey
ultra-esoteric languages, it's pretty much just a bunch of
domain-specific Java/Javascript knockoffs from horizon to horizon.
> I am just surprised that this (to me) rather inelegant design survived
> and got to market, given what you've said about the same company's
> ruthless drive for cost-cutting removed one PCB trace even though it
> killed floppy-disk performance, or wouldn't use an extra ROM chip
> because it was too expensive.
>
> It seems inconsistent.
It's marketing - consistency there is a non-consideration, if not
actively striven against. The whole saga with CP/M on CBM was a
boondoggle - the CP/M cart existed because business customers wanted a
CP/M add-in to run their spreadsheets and their whatnot, but it didn't
end up being a good fit for reasons already stated (slow CPU, slow
disk, 40-column only.) The 128 improved on those points, but not
nearly enough to become competitive with the advancements CP/M
machines had made in that time, and in the process wasted precious
man-hours and drove up the cost and complexity of the unit - and all
the while CP/M had been losing ground to MS-DOS in the business market
for years! But marketing promised it, so it had to happen... :/
Tuesday night I was reading up to see what it might take to revive either of my Amiga 1200?s. As it happens, both appear to have fairly common failure modes. In reading up on the dead video, I learned that it?s often on the Composite Out, but not the monitor. I bought these two systems around ?97/98. I plugged the one with the dead video into the Monitor I?m using, and proceeded to use it for about an hour and a half. It works great with the Gotek floppy emulator.
On a whim, earlier today, when I placed the order with AmigaKit for A3000 batteries, I included the hardware needed to put a IDE-to-CF interface in both the A600 & an A1200, PLUS, a second Gotek. :-) It looks like I?m going to need them. :-)
Zane
Funny how wetware memory works. I have that issue of Popular
Electronics somewhere in my collection and would have seen the
article as I would read it cover to cover after it arrived in mail.
While looking at the issue again, remembered reading next article on
PLL's so probably read the Cyclops article, decided that $25 was way
too much for one chip and never bothered. However, I do have a lot
of old RAM chips so might give it a try some day. What I do recall
about that era that a 1024 bit SRAM cost about $10 in Canada. (That
was in days when we made a profit selling beer for $0.25 at TGIF).
Boris Gimbarzevsky
>I think a Stanford AI lab has one in a display case. Any others out there?
>
>It was supposedly "commercial" but I don't even remember ever seeing
>an ad for the Cyclops from Cromemco and I had a really good stash of
>Cromemco literature and hardware.
>
>I do remember the BYTE article where you pop the top off of a DRAM
>chip to make a Camera but that was 1983-ish, nearly a decade after
>the Cromemco Cyclops was supposedly "commercial". In the discussions
>I had in the 80's none of us seemed to know about the Cromemco
>Cyclops having preceded it.
>
>Tim N3QE
Bill, thanks in particular for the reference to the August 1976 Cromemco catalog. I definitely remember the Dazzler graphics on the cover but somehow had lost memory of the camera on the second to last page.
Tim
So gentlemen, my Alphaserver 4100 shut itself down with a sad announcement
about a dead CPU fan. I have a parts mule which has donated a CPU fan a
couple years ago and I can take the second and last CPU fan from there but
then I have no more fans.
Can the CPU fan be obtained? Can they be rebuilt?
The 4100 has a series of fans between the 3 power supply slots and the
main backplane which I found could not be easily obtained so I tore them
all apart and replaced the bearings with good results but I suspect that
the lttle CPU fans will not respond so well to attempts at repair.
--
Richard Loken VE6BSV : "...underneath those tuques we wear,
Athabasca, Alberta Canada : our heads are naked!"
** rlloken at telus.net ** : - Arthur Black
I think a Stanford AI lab has one in a display case. Any others out there?
It was supposedly "commercial" but I don't even remember ever seeing an ad for the Cyclops from Cromemco and I had a really good stash of Cromemco literature and hardware.
I do remember the BYTE article where you pop the top off of a DRAM chip to make a Camera but that was 1983-ish, nearly a decade after the Cromemco Cyclops was supposedly "commercial". In the discussions I had in the 80's none of us seemed to know about the Cromemco Cyclops having preceded it.
Tim N3QE
The Kennett Classic Gallery of Computing history and shop has re-opened per
State of PA and County of Chester guidelines.
I am looking for volunteers to help with moving some large DEC racks into
the basement area, we decided to expand exhibits to one more room to make
space for the bigger iron, printers, VAX systems, etc. We are installing
new exhibits this month and any help would be appreciated.
I am also looking for a Linux scripting poss. Python programmer for a paid
project through my web programming business (degnanco.com) if anyone here
is interested in a project. Contact me privately.
Kennett Classic
126 S Union St.
Kennett Square, PA 19348
484 732 7041
kennettclassic.com
-Bill Degnan-
Looking for a CompuPro RAM 16 or something similar that will work in an
IMSAI 8080.
Also looking for a few hard sectored (10 sector) 5.25" floppies
Reply off list! Thanks!
- Ethan O'Toole
Hello
I have a couple of VAXstation 3100s - a M38 which boots but has no output
on the console port, and another model which has corrosion on the
motherboard and a PSU which doesn't power up correctly.
The voltage on all of the M38 PSU's pins is OK except for pin 7 (brown)
which is +3.5v to +5.25v DC and is floating at about 0.6v with reference to
ground. I suspect this is why the console port doesn't work (and the LEDs
on the read suggest a RAM problem so I can't tell which chip is faulty), so
I've set about troubleshooting.
Does anyone have any suggestions above and beyond replacing capacitors?
Peter
--
OpenTrainTimes Ltd. registered in?England and Wales, company no.?
09504022.
Registered office: 13a?Davenant Road, Upper Holloway,?London N19
3NW
Until a few minutes ago, my VT240 was operating normally, but now it's
unresponsive (fails during power-on self test).
Normal behavior was: display a checkerboard, then two different
intensity all-white bands growing slowly up from the bottom of the
screen, then a beep and the expected "VT240 Monitor Error 9" (because
I'm using an old B&W composite monitor instead of the DEC VR201 with
special cable). Thereafter, normal operation.
Now, it briefly displays the checkerboard (and all four keyboard lights
turn on, then off); then the Lock and Wait lights come on and nothing
else happens. Blank screen.
Power-OK light on the back is illuminated and 5.19 volts measured on the
board. Haven't checked +12 (or the internally derived keyboard +5) yet.
Another possibly useful observation: I can press the Setup (or any
other) key about four times and hear a keyclick sound each time. But
then it stops playing the click sound if I keep pressing keys. This
suggests that the interrupt on the CPU (a T11) is not being responded to.
The technical manual is very detailed but does not describe the
specifics of the POST, which could be useful in locating the failed
circuit (or firmware).
Can anyone with experience in debugging these terminals lend a hand?
Should I even be looking at the main board, or the keyboard which also
has an 8051 CPU??
thanks.
Hi everyone!
My wife found some interesting VME-looking boards for sale on a surplus
auction website. This is what we scored. Is there any interest for these
here?
1x Main CPU SKP-220-3
4x Sub CPU SKP-221-3 (2 look good, one has a battery that exploded all over
it, one labelled bad CMOS but had a bent pin.)
3x Servo SKP-222-3
1x IO Board SKP-184-2
I have no card cage, no documentation, and no way to test these. Some are
labelled that they tested good in 2008. I'll happily supply pictures for
those interested, but they're essentially 2U VME boards with MC68000 chips
and the main CPU has an MC68HC000 CPU.
They seem to fetch a fair sum on eBay, but just because they're listed at
these prices doesn't mean that they actually sell at that price:
https://www.ebay.co.uk/itm/Seiko-Epson-Accu-Sembler-Robot-Control-Sub-CPU-B…
--
-Jon
+44 7792 149029
I know the response to this might be quite subjective and depends on
your particular interests.
Do BYTE magazines have any collectability (maybe even from a historical
perspective or something else)?
I have to make some decisions about space (the perennial problem for a
collector of course) and I have quite a few of these taking up a few
shelves.
Thank you.
Kevin Parker
You know, reading about this made me dig out the info I had on the Character Oriented Windows ("COW") library. I was reading some of the docs and it occurred to me that it operated much like Windows (probably Windows 1), but what I couldn't find were any "sample" programs or tools to build a program based on the COW library. Does anyone have/know of a sample program that used the library? Was there an SDK for it or was it used only for Microsoft's products?
Just looking for something new/interesting to learn about. Thanks!
Rich
?On 5/22/20, 11:35 AM, "cctalk on behalf of Chuck Guzis via cctalk" <cctalk-bounces at classiccmp.org on behalf of cctalk at classiccmp.org> wrote:
A quick look at the code indicates to me that the Intel translator
CONV86 may well have done the translation in "strict" mode. Of course,
there were other translators, but some of the stuff rings a bell.
For example, the 8080 instruction
INX B
gets translated to
SAHF
INC BX
LAHF
all done because the 8080 16-bit instruction does not affect the zero
and carry flags, but the 8086 instruction INC, does. So there's very
likely a large amount (my experience was at least >30%) of cruft in the
code.
--Chuck
I assume this are not the standard Intel floppy drives????
On Sunday, May 31, 2020 Jan-Benedict Glaw via cctech <jbglaw at lug-owl.de; cctech at classiccmp.org> wrote:
Hi!
I just wanted to drop an email that there's a MDS 80 on eBay:
??? https://www.ebay.de/itm/333612000595
(Please note: The seller, Michael, is a friend of mine, and a former
coworker.)
Thanks,
? Jan-Benedict
--
Today I was working on a new-to-me VT240 which hadn't been powered up in
a long time (possibly 10 years). Hooked it up to an old 9" B&W CCTV
monitor and everything was running fine for 20 minutes or so - when
suddenly an astonishing amount of acrid whitish-gray smoke started
pouring from the vents =8^ O
So I yanked the power cord out and took the case off. Sure enough, one
if not both of the 0.1 uF X-caps on the line filter had cracked open and
my nose confirmed that was the source of the stench.
Fortunately there is no damage to the PC board or surrounding components
- even the caps don't look toasted, just split. Good thing I was sitting
right there when they failed and could turn the power off immediately.
I've read here and elsewhere about the spectacular failure modes of
these caps, sometimes flames, but this is the first time I ever
experienced it first hand. Maybe it's time for a look inside my VT220? ;)
-Charles
Hi, I've recently come across a CPU chip marked "AlphaMicro" . It has a
date stamp of 8531 and appears to be of the 386 variety (1 5/8 x 1 5/8). It
doesn't appear to be from Alpha MicroSystems. Anyone know who may be the
maker of this chip? I can send a picture for those who'd like to see what
it looks like.
Hi!
I just wanted to drop an email that there's a MDS 80 on eBay:
https://www.ebay.de/itm/333612000595
(Please note: The seller, Michael, is a friend of mine, and a former
coworker.)
Thanks,
Jan-Benedict
--
Working on restoring this 11/83, I would like to replace the Fujitsu
2284E drive with a slightly larger capacity CDC/Imprimis WREN VI
94246-383 ESDI. I think I have the jumper configurations, however the
problem is the disk does not have a terminator pack.
Does anyone know what kind of resistor pack was used for the CDC drives?
It's probably something very basic and easy to find at Digikey but what?
Thanks!
Chris
(working away here)
Title says all,
Backing up all the programmable parts in the Apollo DN100 and the CPU board
has a few of these ceramic DIPs with the same Apollo P/N labels as the
Am27S29 and similar programmable parts.
Thanks
Classic Computer Fans,
I tried out the CYBIS release:
http://www.Control-Data.info/CybisRelease.html
on the DtCYBER emulator when it first came out. I've since forgotten most
of what I'd learned. Recently I fired CYBIS back up and started relearning.
Does anyone know if any user mailing lists for the DtCYBER emulator and/or
the CYBIS release? At the moment I'm trying to find a Linux friendly
terminal type that works with NOS's FSE.
--
Kevin
http://www.RawFedDogs.nethttp://www.Lassie.xyzhttp://www.WacoAgilityGroup.org
Bruceville, TX
What's the definition of a legacy system? One that works!
Errare humanum est, ignoscere caninum.
On Fri, 22 May 2020, Boris Gimbarzevsky wrote:
> Thanks for posting the timeline of various Basic interpreters. I wasn't
> aware that Gates/Allen also wrote Basic for C64.
Microsoft did a BASIC for the Commodore PET. I wasn't aware that they did
the C64.
> Did download the 8080 Basic source code out of interest, but in early
> 1980's had very little to do with IBM PC.
PC was 8088, NOT 8080.
BUT, an original 8080 source code can be run through some algorithmic
translation to automagically patch it into something that is close enough
to 8088.
All of my knowledge of the following is third hand, and probably mostly
WRONG. If you are lucky, maybe some of the folk here who actually KNOW
this stuff will step in and give the right information.
Sequence is only approximate.
Well, we can start by considering the 4004. 1971. It was not the "FIRST"
microprocessor, although the later chips based on it dominated the market.
4 bit data bus. It was designed to be able to make a whole range of
Busicom calculators that could be essentially the same hardware, and
changing ROM, or moving a jumper from cheapest model to most expensive
model would void the warranty.
Then came the 8008, with EIGHT bit data bus, and 14 bit address bus (16K
of RAM)
Then came the 8080, with 8 bit data bus and 16 bit address bus (64K of
RAM) That brought about a giant surge in hobbyists trying to build
computers, including the MITS Altair, etc.
It is important to note that each Intel chip consisted of "minor"
modifications to the previous one. That made it easier to modify a design
or software from one to the next one. Minor patches tended to be all
that was needed. THAT is important. 'course it means that some aspects
are really weird due to being patched on top of patched, on top of
patched, instead of redesigned.
MEANWHILE, other companies started trying to get into the game.
Motorola came out with the 6800, which was pretty cool.
But, they were taking a long time to get around to the next ones, so a
group of engineers left and started MOS Technology, and came out with the
6500. Motorola's lawyers were not amused. So, the engineers redesigned
an all new, "non-infringing" one called the 6502.
Motorola eventually got around to trying to design "the best 8 bit
microprocessor", and came out with the 6809.
They had designed from scratch, to try to make it the best, so it had so
much different, that previous machines could not be easily modified for
it, and had to be redesigned for it, and software needed to be re-written,
not just patched.
They had difficulty finding any takers, in spite of obvious design
superiority, because most manufaturers were already established with other
chips. BUT, Radio Shack built a machine called "the Radio Shack Color
Computer" around a Motorola application note. Radio shack didn't want it
competing with their other products, and didn't see any reason to include
capabilities, so they had horrible constraints, such as chiclet keyboard,
unexpandable RF video, cartridge slot instead of expansion bus, etc.
A lot of the early machines were intel 8080, which had 8 bit data bus
and 16 bit address bus, which meant maximum of 64K of RAM, although it was
not very hard to cheat for 128K.
Gary Kildall needed an OS for managing his source code on 8 inch disks
that he added to his computer. He wrote "Control Program and Monitor",
which later became "Control Program for Microcomputers" ("CP/M"). He
tried to get Intel to market it, but they didn't think that there would
ever be enough market to sell an operating system for a microcomputer.
So, he started "Intergalactic Digital Research"
Later, when the hobbyists grew up and lost their sense of humor,
"Thinker Toys" became "Morrow designs". (they had been having some
trademark issues)
"Kentucky Fried Computer" became "Northstar" (they had been having some
trademark issues)
and "Intergalactic Digital Research" bcame "Digital Research Incorporated"
Then Zilog came out with the Z80, which had major enhancements.
BUT, code using those enhancements would not run on an 8080, so CP/M
remained 8080, and many/most? programmers stuck with 8080 for marketable
code.
Intel came out with the 8085, which had DIFFERENT [incompatible]
enhancements, so many/most? continued to stick with 8080 code.
I think that the Radio Shack model 100 is 8085.
A hobbyist named Steve Wozniak wanted to build a Z80 computer. But it was
going to cost too much. At Wescon (trade show), he got a fantastic deal
on some 6502 chips. Not what he had been wanting, but he could make it
work, and he could afford them!
He hooked up with Steve Jobs, who had some marketing ideas. They sold a
bunch of "blue boxes", kited some checks, sold Jobs' VW bus and Woz's
calculator, and put together a batch of kits. ($666.66; they later said
that they had not realized the theological implications of the price)
And, hence, we got "Apple Computer". Later, Apple Music (Beatles) talked
to them about the name. Apple Music agreed to not get into computers, and
Apple Computers agreed to not get into music. Hmmm.
Atari and Commodore both ended up also using the 6502.
Motorola
Then Intel decided to build a "16 bit processor". The 8086 has a 16 bit
data bus and a 20 bit address bus, for a maximum of 1M or RAM
When the IBM PC wasbeing planned, there was a lot of difference in cost
between 8 bit and 16 bit support chips.
The 8088 was ALMOST the same as an 8086, but with an 8 bit data bus, which
significantly reduced costs! From an engineering perspective, the 8088 is
an 8 bit version of the 16 bit 8086.
>From a MARKETING perspective, it's 16 bit, or maybe 32 bit, or maybe 64
bit, etc. If a 4 bit machine has a 128 bit Smell-o-vision port,
marketing will call the machine "128 bit"
The IBM PC was an 8088.
IBM went to Microsoft to get BASIC for it. Bill gates put on a suit and
met with them.
The "Pirates Of The Valley" story of Microsoft cold-calling IBM to sell an
operating system PINS THE NEEDLE ON THE BOGUSIMETER. The author of that
fiction needs a hot soldering iron shoved 8 inches up his nose.
Microsoft was happy to oblige on BASIC.
One of the IBM engineers had an Apple2 with a Microsoft "Softcard" (Z80)
to run CP/M. So, IBM asked Microsoft to also supply "the CP/M".
Bill Gates explained that that was Digital Research.
So, IBM went to Digital Research in Pacific grove to get "the CP/M".
There was some "culture clash". IBM showed up in blue suits. There is an
unconfirmed report that somebody at DR thought that it was a drug raid. I
have looked out that upstairs window, and can imagine it.
The IBM suits encountered barefoot workers in shorts and not all wearing
shirts (both sexes?) female workers without bras. cats and a dog. plants.
Surfboards and bicycles in every room.
Gary Kildall wasn't even THERE! He had gone to fly his plane up to
Oakland to visit Bill Godbout. Official story is that that was an
essential errand to deliver some documentation (and no lower employee
could have put some shoes on and driven up?). His wife was there, and he
had told her, "They're just coming to sign a license agreement. Let them
wait in the living room with the rest of the customers."
IBM was not amused.
IBM went back to Microsoft. I heard that Bill Gates told his people that
anybody without a suit should stay home for the day.
IBM said that they wante Microsoft to provide the OS. Bill Gates said,
"we do BASIC. We don't do operating systems." IBM said that they
intended to get the BASIC and the OS from ONE source. Bill Gates said,
"Let me tell you about our new OS department!"
Then Bill Gates went down the street to Seattle Computer Products and
bought 86-DOS/QDOS ("Quick and Dirty OS"), including hardware to run it
on, and the contract of Tim Paterson who wrote it.
Microsoft had a new OS department.
Motorola STARTED work on "The best 16 bit processor". Rather than
patching something earlier, and being stuck with legacy oddities, they
designed from scratch. So, it took longer.
Motorola eventually came out with the 68000, which was the best 16 bit
processor. (or 32 bit or 64 bit if you are in marketing)
The Apple3 was a major financial setback. Much more money, for very
little more.
Apple started on a total redesign. It is rumored that for the Lisa, they
explicitly avoided anybody with prior experience to avoid repeating
previous bad ideas. 'course hiring brilliant folk straight out of college
meant that nobody had the prior experience to know the consequences of
building a machine for which software could NOT just be patched from
previous versions. The Lisa was magnificant! and in a price range
(>$20K?) where sales were to overpaid exectuvies wanting to impress other
overpaid executives. It actually came close to putting Apple on the rocks.
And, it was an ALL-NEW (and improved) machine. Old software couldn't just
be patched, it had to be re-written.
The brilliant recovery plan was to take the Lisa design and cut every
corner that could be cut, to make a machine that could be sold for $500.
Once they did, they found that they could still get away with selling it
for $2K. it was mandated that the resulting machine would come with four
significant pieces of software. By the time it was ready, those had
become Mac-Write, Mac-Paint, Mac-Write, and Mac-Paint. But that was
enough. The marketing people were smart enough to change the grumbling
about building a computer for ignorant masses into "a computer for the
rest of US"
Later, Commodore (Amiga) and Atari (ST) used the 68000. There are some
amazing stories (that i don't know) about that "technology swap"
Intel came out with the 80286, 16 bit data bus with 24 bit address
bus. with fewer limitations. But still a few
significant ones, such as how to switch in and out of "protected mode".
"It's like having to turn your engine off to switch gears on the freeway".
Bill Gates called the 80286, "Brain dead."
In "real mode", which would be limited to 20 bits of address, it is easy
to cheat and enable A20, which permits 64K past the 1M boundary. THAT is
required for Windoze 3.10
Then came the 80386, which could sorta be called a 32 bit processor. And
the 80386-SX, which analogous to the 8088, was a 16 bit version of the 32
bit 30386, permitting building a software compatible machine using cheap
80286 support chips.
80486, which is kinda like a 80386 plus 80387 math chip, and the 80486SX,
with is 80486 without the math processor.
and Pentium. Intel had been finding out the hard way that it was
difficult to maintain trademark of a number (Oldsmobile "442"
notwithstanding) Other manufacturers would make a 80386 like chip and
call it a 486, or an 80486 like chip and call it a 586, etc. So, they had
a naming session. And the other entries were even worse than "Pentium".
I'm surprised that that didn't backfire horribly! Consider: In about
1965, Honeywell bought Pentax from Asahi. Honeywell could totally
legitimately have come out with a processor (joint venture with
AMD/Cyrix/etc.?) and called it the "Pentaxium". Intel wouldn't even be
able to object.
Yeah, there have been more since then, but new stuff isn't interesting for
another ten or twenty years. OR MORE for some of the boring current
stuff.
--
Grumpy Ol' Fred cisin at xenosoft.com
> As was working with PDP-11's at that time, really disliked 8080 instruction
> set and got a C64 instead which was considerably cheaper than IBM PC and much
> easier to write assembly code for. C64 basic is fairly ugly but bought a
> 6502 assembler and just used Basic to display stuff on screen and call my
> work was done in assembly language code. Had no trouble sampling switch data
> at 1 KHz using my "toy" computer. A couple of guys from UBC Physiology
> decided to build a programmable stimulator based on C64 which they were
> trying to sell for $2K, considerably less than the ~$10 K that the dedicated
> device that was commonly used then. Even though their timing specifications
> matched the expensive device, a lot of researchers back then didn't want a
> "toy" to be part of their lab setup so sales were few.
>
> Recently found a movie Pirates of Silicon Valley which had some of early
> Microsoft history and, if depictions of individuals are true to reality,
> explains why I far preferred Mac in comparison to ugly early windows. It
> also helped that 68000 was a very easy processor to migrate to after 8 years
> doing assembler/FORTRAN programming on a PDP-11. Couldn't believe it when I
> had a full 512 Kb of RAM to play in.
> From: Jon Elson
> As far as I know, there was no VM/360. There WAS VM/370, which was out
> in the early 1970's
CP/67, which was a semi-product, and ran only on 360/67's, was basically the
same functionality as VM/370. (I get the impression that the code was
descended from CP/67, but I can't absolutely confirm that - although see
Varian, below.) It was used by many customers who had purchased 360/67's.
The 370/67's instruction set didn't need to be tweaked at all to run a
virtualization (although it had added hardware to do virtual memory, which
CP/67 needed); the '360 Principles of Operation' was defined in such a way
that it could be virtualized. (Unlike, say, the PDP-11, where a RESET
instruction in User mode is a NOP, and does not trap). All that's needed is
the virtual memory hardware, because otherwise the real addresses of the
underlying machine have to be exposed to the virtual machines.
CP/67 was preceded by two earlier iterations: CP/40, which ran on a special
360/40 which has been hacked to have paging hardware added; it was likewise
almost identical to CP/67 (a hacked version of CP/40, with the memory
management of the 370/67 substituted for the special 360/40's, was booted on a
360/67). An older system, M44, which was similar in functionality (although
not a perfect virtualization of the underlying machine), it ran on a modified
7044.
One version of CP/67 provided a /370 virtual machine; it was used
extensively by the MVS development team. CP/67 was also brought up on
/370 hardware.
Full details in "VM and the VM Community: Past, Present and Future",
by Melinda Varian.
Noel
Still looking for the matching? paper tape reader and punch.? For one of these...Ed#
On Sunday, May 31, 2020 Jan-Benedict Glaw via cctech <jbglaw at lug-owl.de; cctech at classiccmp.org> wrote:
Hi!
I just wanted to drop an email that there's a MDS 80 on eBay:
??? https://www.ebay.de/itm/333612000595
(Please note: The seller, Michael, is a friend of mine, and a former
coworker.)
Thanks,
? Jan-Benedict
--