[cctalk] Re: Random items on Pascal #3

[Warner Losh via cctalk]

On Thu, May 9, 2024, 6:10 PM Paul Koning via cctalk 
wrote:

>
>
> > On May 9, 2024, at 7:55 PM, Fred Cisin via cctalk 
> wrote:
> >
> >>> ...
> >>> I've written code in Pascal, as well as Modula-2.  Never liked
> >>> it--seemed to be a bit awkward for the low-level stuff that I was
> doing.
> >
> > On Thu, 9 May 2024, Paul Koning via cctalk wrote:
> >> Not surprising, since that's not what it is all about.  Both, like
> their predecessor ALGOL-60 as well as successors like Ada, are strongly
> typed languages where doing unsafe stuff is made very hard.  Contrast that
> with C, which sets out to make it easy to do unsafe things and partly for
> that reason has a feeble type system.  So doing low level stuff like device
> drivers is difficult, unless you create extensions to break out of the type
> system.  An example of how to do that is the Burroughs extension of ALGOL
> called ESPOL, which is what they used to write the OS.  Actually, Burroughs
> did a number of extended versions for different purposes; there's also
> DCALGOL (Data comm ALGOL) intended for writing communications software.
> Why that's separate from ESPOL I don't really know; I only ever got to do
> regular ALGOL programming on Burroughs mainframes.  One reason for that:
> those systems depend on the compilers for their security; if ordinary users
> got access to ESPOL they could write dangerous code, but in ALGOL they
> cannot.
> >
> > One of the things that _I_ love about C is that it is easy to get it out
> of the way when you want to do something lower level.
> >
> > Rather than feeble type system, it could have had a requirement to
> explicitly "cast" anything being used as a "wrong" type.
> >
> > One of Alan Holub's books about C is titled
> > "Enough rope to shoot yourself in the foot"
>
> True, and Stroustrup added that "and C++ is a cannon that blows off your
> entire leg".
>

The other joke is that C++ lets you shoot off the 27 identical legs you
didn't know you had...

Warner

> Each language has its own specialty.  And you need to find the one that
> fits you best.
> >
> > It used to be (and likely still is), that every computer science grad
> student created a new language.  A requirement (usually UNSPOKEN) was that
> the compiler be able to compile itself.  That the language compiler is
> written (actually normally RE-written) in that language and compiled by
> that compiler.  That certainly seems to bias things towards languages that
> are well suited for writing compilers!  If you were to create a language
> that was specializzed for something completely different, and poorly suited
> for writing compilers, then it would not be respected.
>
> If you don't mind the total lack of protection, FORTH is very nice: it
> even more easily than C lets you do low level things, and it is also very
> small.  And the implementation is by definition entirely extensible.  A
> large FORTH program I wrote in the 1980s, on PDP-11 FORTH, starts out by
> redefining the language as a 32-bit version.
>
> I still remember a classmate of mine, who told me when we were both at DEC
> that he had written an expression parser in COBOL.  I think he also tried
> to do one in RPG but found it was too hard.
>
> paul
>
>

[cctalk] Re: DOS p-System Pascal: (Was: Saga of CP/M)

[Warner Losh via cctalk]

On Thu, May 9, 2024, 5:39 AM Bill Degnan via cctalk 
wrote:

> Without doing the research before asking, there was the UCSD p-System
> Pascal for IBM PC which came out very early in the history of the IBM PC.
> It was not very popular.  The SAGE II that had native Pascal (68000) was
> not a popular machine.  Waterloo Pascal on the SuperPetPascal never
> really made it on the microcomputer platform did it?
>

Not until TurboPascal... But it was only a few years until C emerged from
the language "street fight" as top dog... depending on what the universe of
microcomputers we're talking about.

Warner

Bill
>
> On Thu, May 9, 2024, 2:07 AM david barto via cctalk  >
> wrote:
>
> > At Ken Bowles retirement from UCSD (Ken was the lead of the UCSD Pascal
> > Project) he related a story that IBM came to UCSD after being ‘rejected’
> by
> > DR to see if the Regents of the University would license UCSD Pascal (the
> > OS and the language) to IBM for release on the new hardware IBM was
> > developing. The UC Regents said ’no’.
> >
> > He was quite sad that history took the very different course.
> >
> > David
> >
> > > On May 3, 2024, at 6:30 PM, Fred Cisin via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> > >
> > > PL/M (think "PL/1") was a high level programming language for
> > microprocessors.
> > >
> > > CP/M was also briefly called "Control Program and Monitor"
> > > It was written by Gary Kildall. (May 19, 1942 - july 11, 1994)
> > >
> > > Gary taught at Navy Postgraduate School in Monterey.
> > > He took a break in 1972, to complete his PhD at University of
> Washington.
> > >
> > > He wrote 8008 and 8080 instruction set simulators for Intel, and they
> > loaned him hardware.
> > >
> > > In 1973? he wrote CP/M.
> > > He offered it to Intel, but they didn't want it, although they marketed
> > the PL/M.
> > >
> > > He and his wife started "Intergalactic Digital Research" in Pacific
> > Grove. Later renamed "Digital Research, Inc."
> > >
> > > CP/M rapidly became a defacto standard as operating system for 8080 and
> > later Z80 computers.
> > >
> > > In the late 1970s, when CP/M computers were available with 5.25"
> drives,
> > and there were hundreds, soon thousands of different formats, I chatted
> > with Gary, and pleaded with him ot create a "standard" format for 5.25".
> > > His response was a very polite, "The standard format for CP/M is 8 inch
> > single sided single density."
> > > I pointed out that formats were proliferating excessively.
> > > His response was a very polite, "I understand. Sorry, but the standard
> > format for CP/M is 8 inch single sided single density."
> > >
> > >
> > > In 1980? IBM was developing a personal computer. (y'all have heard of
> > it) One of the IBM people had a Microsoft Softcard (Z80 plus CP/M) in his
> > Apple.  IBM went to Microsoft, to negotiate BASIC for the new machine,
> and
> > CP/M.
> > >
> > > Bill Gates explained and sent them to Digital Research.
> > >
> > > When the IBM representatives arrived, Gary was flying his plane up to
> > Oakland to visit Bill Godbout.  He hadn't seen a need to be present, and
> > assumed that Dorothy would take care of the [presumably completely
> routine]
> > paperwork. While visiting Bill godbout, and delivering some software was
> > important, it WAS something that a low level courier could have done.
> > >
> > >
> > > There was a little bit of a culture clash.
> > > The IBM people were all in identical blue suits.
> > > The DR people were in sandals, barefoot, shorts, t-shirts, braless
> > women, with bicycles, surfboard, plants and even cats in the office,
> > >
> > > The IBM people demanded a signed non=disclosure ageement before
> talking.
> > Dorothy Kildall refused.
> > >
> > > When Dorothy got Gary on the phone, it is unreliably reported that he
> > said, "well, let them sit on the couch and wait their turn like the rest
> of
> > the customers."
> > >
> > > It is also been said that DR people upstairs saw the IBM people
> marching
> > up, and thought that it was a drug raid.  I have stood in that bay window
> > overlooking the front door, and can believe that.
> > >
> > > IBM chose to not do business with DR and went back to Microsoft.
> > > When billg was unable to convince them that Microsoft was not in the
> > operating system business, Microsoft went into the operating system
> > business.  They bought an unlimited license to QDOS (Tim Paterson's work
> at
> > Seattle Computer Products).  They also hired Tim Paterson.
> > >
> > > DR was working on CP/M-86, but it was a ways off.
> > > Paterson had written QDOS ("Quick and Dirty Operating System") as a
> > placeholder to be able to continue development while waiting for CP/M-86
> > > We've mentioned before, that Tim Paterson got the idea for the
> directory
> > structure from Microsoft Standalone BASIC.  As Chuck pointed out, that
> was
> > not a new invention, merely a choice of which way to do it.
> > >
> > > billg knew how to deal with officious 

[cctalk] Re: MS-DOS source code

[Warner Losh via cctalk]

On Thu, May 2, 2024, 7:27 AM geneb via cctalk  wrote:

> On Thu, 2 May 2024, Will Cooke via cctalk wrote:
>
> > Some may find this interesting.  Microsoft has released the source for
> MS-DOS versions 1.25, 2, and 4.
> >
> > https://github.com/microsoft/MS-DOS
> >
>
> I think the most interesting thing about this is that they published it
> under an actual open source license (MIT) and not that nonsense that was
> used when they released 1.25 and 2.0 through the CHM years ago.
>


Yes. I'd thought about trying to reconstruct the source to the Rainbow
version(s) of DOS, but the license soured me on the idea.

Warner

g.
>
>
> --
> Proud owner of F-15C 80-0007
> http://www.f15sim.com - The only one of its kind.
> http://www.diy-cockpits.org/coll - Go Collimated or Go Home.
> Some people collect things for a hobby.  Geeks collect hobbies.
>
> ScarletDME - The red hot Data Management Environment
> A Multi-Value database for the masses, not the classes.
> http://scarlet.deltasoft.com - Get it _today_!
>

[cctalk] Re: Drum memory on pdp11's? Wikipedia thinks so....

[Warner Losh via cctalk]

On Mon, Apr 15, 2024 at 8:00 AM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

>
>
> A README in the root of 2.11 says:
>
> The following manual pages are NOT in 2.10BSD but ARE in 4.3BSD:
>
> and one of them is drum.4
>
> so, I guess we need to look at a 4.3BSD system to find out what
> drum they are talking about.  I have a feeling this is a device
> that works on the VAX but is actually not found on any PDP-11.
> Why it automatically makes the device node is beyond me.
>

Likely because MAKEDEV was copied over from 4.3's version. We've grown
spoiled with dynamic device population, but even 4.4BSD had static creation
with MAKEDEV.

This is just the paging device for the system. It has nothing to do with
old-school hardware, apart from the name. It's a logical device that spills
over all the configured swap partitions / disks.

 The PDP-11 2.*BSD never had /dev/drum that was functional.

Warner

[cctalk] Re: Amoeba OS

[Warner Losh via cctalk]

On Thu, Mar 28, 2024, 5:37 PM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

>
> I know this is a real long shot but is there any chance someone
> has a copy of the original distribution of the Amoeba OS from
> the University in the Netherlands?  Searching the web finds only
> the current version which runs on X86.  I am looking for the
> original which also ran on Sparc and (of the most interest to
> me) the VAX.
>

https://github.com/OSPreservProject/amoeba has the sun binaries but not the
vax/mips binaries.

Warner

Remember when they said now that we had the web nothing would
> ever be lost again?  :-(
>
> bill
>

[cctalk] Re: How to shutdown RT11?

[Warner Losh via cctalk]

On Fri, Mar 22, 2024, 10:54 PM Zane Healy via cctalk 
wrote:

> On Mar 21, 2024, at 6:19 PM, W2HX via cctalk 
> wrote:
> >
> > I just got a pdp-11 to boot and it seems to have rt-11 installed.  How
> do I do an orderly shutdown? Google has info on simh but this ain't that.
> >
> > Thanks!
> > 73 Eugene w2hx
>
> In this respect it’s similar to many personal computer OS’s of the time
> frame, in that you can simply turn it off.  It’s a fantastic OS in its
> simplicity, and a great way to learn about the PDP-11.
>

Even v7 Unix didn't have halt or reboot.

Warner

>

[cctalk] Re: DEC Processor Books

[Warner Losh via cctalk]

On Sun, Mar 17, 2024, 12:54 PM Douglas Taylor via cctalk <
cctalk@classiccmp.org> wrote:

> >> That matches what a DEC FE told me, at least about the VAX version: the
> >> people were just DEC employees that caught somebody's eye when they were
> >> planning the shots. Don't think they got extra modeling fees..
> > I wouldn't expect modeling fees, given the wording of the standard
> employee agreement.
> >
> >   paul
> >
> I can't imagine a company using staff for photo ops.  Young people now a
> days have tattoos, piercings and wear tee-shirts and flip-flops to work.
>

The 70s and 80s were a different time.. before business casual was a
thing...

Warner

>

[cctalk] Re: DEC Processor Books

[Warner Losh via cctalk]

On Sun, Mar 17, 2024, 11:51 AM Paul Koning  wrote:

>
>
> > On Mar 17, 2024, at 12:35 PM, Warner Losh via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > On Sun, Mar 17, 2024, 10:12 AM Jon Elson via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> >
> >> On 3/17/24 09:13, Bill Gunshannon via cctalk wrote:
> >>>
> >>> I have often wondered about the people we find in the various
> >>> DEC Processor (and other) books.  Were they models in staged
> >>> photo-sessions or were these candid shots from DEC facilities
> >>> and if so, can anyone identify who they might be.
> >>
> >> I know that a guy I used to work for, who later hired on at
> >> DEC, was on a cover of one of the DEC publications.  Yes,
> >> the photos were certainly stages shots, but at least one
> >> person was not a hired model.
> >
> > That matches what a DEC FE told me, at least about the VAX version: the
> > people were just DEC employees that caught somebody's eye when they were
> > planning the shots. Don't think they got extra modeling fees..
>
> I wouldn't expect modeling fees, given the wording of the standard
> employee agreement.
>

DEC was often frugal in the early days...

Warner

>

[cctalk] Re: DEC Processor Books

[Warner Losh via cctalk]

On Sun, Mar 17, 2024, 10:12 AM Jon Elson via cctalk 
wrote:

> On 3/17/24 09:13, Bill Gunshannon via cctalk wrote:
> >
> > I have often wondered about the people we find in the various
> > DEC Processor (and other) books.  Were they models in staged
> > photo-sessions or were these candid shots from DEC facilities
> > and if so, can anyone identify who they might be.
>
> I know that a guy I used to work for, who later hired on at
> DEC, was on a cover of one of the DEC publications.  Yes,
> the photos were certainly stages shots, but at least one
> person was not a hired model.
>

That matches what a DEC FE told me, at least about the VAX version: the
people were just DEC employees that caught somebody's eye when they were
planning the shots. Don't think they got extra modeling fees..

Warner

>

[cctalk] Re: mod.sources archive?

[Warner Losh via cctalk]

On Sun, Mar 3, 2024 at 1:11 PM Dennis Boone via cctalk <
cctalk@classiccmp.org> wrote:

>  > Maybe https://archive.org/details/usenet-mod It includes
>  > mod.sources.mbox.zip
>
> Thanks, didn't think of that.  I've found things in there before.
>
> That takes us back into 1984.  The net.* hierarchy is also in the same
> collection, and its net.sources mbox goes back to ~1982.
>
> Anyone know of an archive that has stuff older than 1982?
>

How much is older than that? I didn't think uucp got going until V7
was released outside of AT in 1980 or 81... I'm sure someone
will correct my notions though :)

Warner

[cctalk] Re: 86-DOS disks...

[Warner Losh via cctalk]

I love seeing people I've chatted with here in other contexts. Lars and
Zork was a recent one too...

Warner

On Sun, Jan 7, 2024, 11:34 AM John Herron via cctalk 
wrote:

> Really cool btw. I thought it was neat that someone on slashdot also
> acknowledged the interesting nature of yours being the earliest version now
> found.  A few days after your post but recognized your username
> https://www.slashdot.org/story/423289
>
> On Sun, Dec 31, 2023, 2:37 PM geneb via cctalk 
> wrote:
>
> > For those interested, I've imaged a couple of super rare (actually rare,
> > not "ebay" rare) original 86-DOS disks.
> >
> > https://archive.org/details/86-dos-version-0.1-c-serial-11-original-disk
> >
> https://archive.org/details/86-dos-version-0.34-c-serial-221-original-disk
> >
> > Both will boot under simh.
> >
> > g.
> >
> >
> > --
> > Proud owner of F-15C 80-0007
> > http://www.f15sim.com - The only one of its kind.
> > http://www.diy-cockpits.org/coll - Go Collimated or Go Home.
> > Some people collect things for a hobby.  Geeks collect hobbies.
> >
> > ScarletDME - The red hot Data Management Environment
> > A Multi-Value database for the masses, not the classes.
> > http://scarlet.deltasoft.com - Get it _today_!
> >
>

[cctalk] Re: RIP: Software design pioneer and Pascal creator Niklaus Wirth

[Warner Losh via cctalk]

My first two pascal programs of any size were an Alarm Clock for my DEC
Rainbow and a PDP-11 simulator, also for my DEC Rainbow (I did a science
fair project comparing stack machines to traditional ones, but invented my
own stack machine and was too young to know the right way to
compare/contrast the two different machines, so I scraped by with a better
than average rating... mostly because nobody knew how to evaluate it, but
that was to my advantage thinking back on it...). Ah, fond memories of
Turbo Pascal.

Lack of strings, and lack of a good way to do portable I/O doomed the
language.

Warner

[cctalk] Re: Good C to FPGA/PLA compiler

[Warner Losh via cctalk]

On Sat, Sep 23, 2023, 12:31 PM Paul Koning via cctalk 
wrote:

>
>
> > On Sep 22, 2023, at 3:07 PM, Chuck Guzis via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > On 9/22/23 11:34, emanuel stiebler via cctalk wrote:
> >
> >> There are still some 84pin chips out there(Altera & Xilinx). Sometimes
> >> they are pulls, or some 5V tolerant xilinx xc95l
> >
> > I still have a few 84 pin PLCC XC95108 5V CPLDs  Originally, I did a
> > tape controller design with one before Xilinx discontinued them.  I
> > figured that using a discontinued part was not the way forward, so I
> > dropped the project.   Xilinx did/does have its ISE design suite, which
> > is fairly easy to use.
> >
> > Eventually, it turned out that using a reasonably fast MCU with 5V
> > tolerant I/O worked just as well and avoided the "mystery in a chip" of
> > a CPLD.
>
> I used an Arduino Feather that way, for my PS-2 to LK201 converter.  And
> while not 5V tolerant, a Raspberry Pico is a particularly powerful and
> cheap option; one of my projects could run DDCMP at 10 Mb/s including the
> "integral modem" compatible signaling.
>
> As I mentioned, 5V tolerant inputs can, at least for not too high speeds,
> be done simply by resistive voltage dividers.
>

What's too fast in absolute terms?

Warner

paul
>
>
>

[cctalk] Re: For Fred, especially: "Everything I know about floppy disks"

[Warner Losh via cctalk]

On Sun, Sep 10, 2023, 4:12 PM Will Cooke via cctalk 
wrote:

>
>
> > On 09/10/2023 3:00 PM CDT Fred Cisin via cctalk 
> wrote:
> >
> >
> > On Sun, 10 Sep 2023, Chuck Guzis via cctalk wrote:
> > > Now, let's talk about 2.8" and 3.25" drives; UK readers are certainly
> > > familiar with 3.0 inch CF drives used on Amstrads.
> > Amdek? sold a dual 3" drive in USA, marketed as external drives.
> > There were ads for it in one or more of the Coco magazines.
> >
> > And there were ads for it as external drives for Apple2!
> > Q: were those different electronics? OR did they include an FDC for
> > Apple2?
> >
> >
> > 3.25:
> > The three leading contenders for "Shirt pocket disks" were 3", 3.25", and
> > 3.5". There were many others, such as a 3.9" that IBM was rumored to be
> > planning.
> > But, for shirt pocket puspose, 3" seems the most promising.
> > There was extensive argument in the trade journals.
> > George Morrow said, "Why don't we get the clothing industry to make
> > shirt pockets 5.25 inch?"
> >
> > Dysan did not want such an extreme retooling, so they were pushing the
> > 3.25", which was basicaally a smaller 5.25", with a metal hub. They
> > reasoned that whichever size had the most software would end up being the
> > winner. So, Dysan set up an enormous software publishing venture. Before
> > there were any machines using 3.25", you could purchase most of the major
> > software packages on 3.25" disks! I ended up with a few drives and disks
> > from Micropro.
> >
> > But, then HP and Apple both went with 3.5".
> > When IBM went with 3.5" (PS/2, PC-DOS 3.20), the coffin was nailed shut.
> > Seequa Chameleon 325 seems to have been the only machine that made it to
> > market with 3.25" drives.
> >
> > Dysan had invested so much into their software publishing venture to
> > promote 3.25" that, when 3.25" died, they couldn't ever recover. R.I.P.
> >
> >
> > --
> > Grumpy Ol' Fred ci...@xenosoft.com
>
>
> I make an official motion that Fred write his own "Everything I Know About
> Floppy Disks" page / book /encyclopedia.
>
> I suspect that what is inside his head is the greatest collection of
> knowledge about floppies on the planet.
>
> Fred, you will be paid with great admiration and appreciation.  Sorry, all
> I can offer. :-)
>
> Anyone with me?
>

I am. I thought I was hot shit with what I knew about floppies. And for the
tiny sliver I needed for my Rainbow hacking, I kinda sorta knew enough.
This thread and all the others shows I know next to nothing.

Warner


> Will
>
>
> If you want to build a ship, don't drum up people to collect wood and
> don't assign them tasks and work, but rather teach them to long for the
> endless immensity of the sea.
>
> Antoine de Saint-Exupery
>

[cctalk] Re: Silly question about S-100 and video monitors

[Warner Losh via cctalk]

On Wed, Aug 30, 2023 at 1:52 PM Mike Katz via cctalk 
wrote:

> I had a video board and keyboard on my Gimix SS-50 system.
>
> Why?
>
> 1.  The video board/monitor is much faster than a terminal even at
> 115,200 baud.
>

115,200 in the S100 era was also rare. It was usually 9600 or 19200 at the
top end.


> 2.  A Video board, keyboard and monitor was way cheaper back then than a
> terminal (Yes there was the SWTPc CT64 and the Lear Siegler ADM-3A kits,
> but fully loaded they weren't all that cheap).
> 3.  If the video board supports any kind of graphics that is another
> reason.  The Gimix video board supported graphics with a RAM character
> generator.
>

4. It's a lot less code to directly splat characters into memory than to
generate
all the escape sequences you need to 'draw' anything interesting (be it a
game,
a graph or just an emacs buffer).

I got into this just after the S100 era, and I opted for the Rainbow
because it
was both a terminal I could connect to other systems, and a system with an
internal graphics card. The terminal had completed the move inside the
computer
after starting out life as a computer added onto the terminal. DECs
terminals
followed this path. Many of the S100 systems that had graphics cards were
also
chasing after newish workstations that were just starting to be built.

Warner


> On 8/30/2023 2:38 PM, W2HX via cctalk wrote:
> > Hi all,
> >
> > I recently acquired an S-100 computer, and it came with a video card and
> a keyboard (3rd party products, not originally equipped with these). I am
> trying to figure out the benefits of having a video card and keyboard vs
> just using a serial port and terminal. Certainly if the video card
> supported graphics, that would be a reason to go that route over a
> terminal. As for the keyboard, ok-maybe you need specific keys for a
> specific application. But I don't understand the video monitor. I could
> understand maybe if there was an RF modulator so that you could use a
> standard TV. That would save the builder some money. But this computer just
> provides composite.
> >
> > Other than graphics (and maybe some special function keys for an
> application on a keyboard), why would an S-100 builder in those days opt to
> buy a video card instead of a terminal?
> >
> > Thanks for the bandwidth.
> >
> > 73 Eugene W2HX
> > Subscribe to my Youtube Channel: https://www.youtube.com/@w2hx/videos
> >
>
>

[cctalk] Re: Emacs on v7

[Warner Losh via cctalk]

On Thu, Aug 24, 2023 at 5:26 PM Adam Thornton via cctalk <
cctalk@classiccmp.org> wrote:

> I finally got an Emacs running on v7--it's on misspiggy at LCML now as
> "ue".
>
> It's Microemacs 3.6; what I did was to clone
> https://github.com/troglobit/MicroEMACS and check out the first commit.
>
> Some experimentation later, it had the usual problem with v7 and DEC
> linkers that not all the function names (er, more generally exported
> symbols, but in this case, function names) were unique in the first 7
> characters (which is 6 if you're working with DEC OSes).  So a bit of sed
> later and I had something that built, linked, and appears to run with
> TERM=vt100 set.
>

The usual hack was to use '#define somethingLong sl23'... did that
not work here?


> Arrow keys, naturally, don't work, but C-b, C-f, C-p, C-n do.
>
> I think I'm going to just make a GH repo of it, but I'm happy to send the
> tarball, or tar.uue, upon request.  I find UUCP kinda fragile on my simh
> installation, and I don't know how to get to Miss Piggy's (although the
> uucp commands are there), so, well, uuencoding, a pasteboard buffer,
> iTerm2's "Paste Slowly", and cat will work as a file transfer mechanism.
>
> Now I'm going to run over to TUHS and announce the same.
>

Cool. there were a lot of different micro emacses... why'd you choose
this one / this version?

Warner

[cctalk] Re: Connecting MFM emulator as both 1st and 2nd drive in Microvax 2000?

[Warner Losh via cctalk]

On Sun, Aug 13, 2023, 10:20 AM Nigel Johnson Ham via cctalk <
cctalk@classiccmp.org> wrote:

> On 2023-08-13 12:18, Warner Losh via cctalk wrote:
> > On Sun, Aug 13, 2023, 10:11 AM Chuck Guzis via cctalk<
> cctalk@classiccmp.org>
> > wrote:
> >
> >> On 8/13/23 08:39, Nigel Johnson Ham via cctalk wrote:
> >>
> >>> You've amplified my point, Fred!   When I saw the abomination of
> >>> cross-over selects in the cables in the IBM PC, I knew the need for
> >>> Field Service Engineers was coming to an end!
> >>>
> >>> I don't believe anything on Wikipedia anymore.  When I saw them say
> that
> >>> there is no such thing as a legal definition for a pint of beer in
> >>> Canada, I got an actual legal definition from the Federal Government,
> >>> created an account on wikipedia, and put in the correct legal
> definition
> >>> with a reference to the law. (It's 568.26 ml btw - make sure you get
> >>> that last .26ml :-) )
> >>>
> >>> I week later it had been changed back to the previous text, and I could
> >>> not get in to correct it!
> >> You should see the "interesting" cabling for getting three drives on a
> >> PC controller, using only one cable.  Several ISA SCSI and ESDI
> >> controllers could accommodate this on their floppy section..
> >>
> >> At least one DTC controller allowed for running 4 drives the way Al
> >> Shugart intended--common motor, different drive selects.
> >>
> > The DEC Rainbow did that... insert rx50 disclaimer... I did it with 2
> teac
> > drives that both spun on any access
> >
> >   and some early NEC computer I saw at computer land iirc... or maybe the
> > latter just kept the drives spinning
> >
> > Warner
> >
> > --Chuck
> >>
> >>
> The DEC Rainbow RX50s only have one motor :-)
>

True.. but if you put a pair of teac fd55f drives, suitably jumpered, they
both came on... and could do double sided media...

Though in the dual setup mode, only one of the rx50s would spin up... so
maybe not as true for that reason.

Warner

-- 
> Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
> Amateur Radio, the origin of the open-source concept!
> Skype:  TILBURY2591
>
>

[cctalk] Re: Connecting MFM emulator as both 1st and 2nd drive in Microvax 2000?

[Warner Losh via cctalk]

On Sun, Aug 13, 2023, 10:11 AM Chuck Guzis via cctalk 
wrote:

> On 8/13/23 08:39, Nigel Johnson Ham via cctalk wrote:
>
> > You've amplified my point, Fred!   When I saw the abomination of
> > cross-over selects in the cables in the IBM PC, I knew the need for
> > Field Service Engineers was coming to an end!
> >
> > I don't believe anything on Wikipedia anymore.  When I saw them say that
> > there is no such thing as a legal definition for a pint of beer in
> > Canada, I got an actual legal definition from the Federal Government,
> > created an account on wikipedia, and put in the correct legal definition
> > with a reference to the law. (It's 568.26 ml btw - make sure you get
> > that last .26ml :-) )
> >
> > I week later it had been changed back to the previous text, and I could
> > not get in to correct it!
>
> You should see the "interesting" cabling for getting three drives on a
> PC controller, using only one cable.  Several ISA SCSI and ESDI
> controllers could accommodate this on their floppy section..
>
> At least one DTC controller allowed for running 4 drives the way Al
> Shugart intended--common motor, different drive selects.
>

The DEC Rainbow did that... insert rx50 disclaimer... I did it with 2 teac
drives that both spun on any access

 and some early NEC computer I saw at computer land iirc... or maybe the
latter just kept the drives spinning

Warner

--Chuck
>
>
>

[cctalk] Re: Old Professional/350 software, any of this out there

[Warner Losh via cctalk]

Paul,

Doesn't .IMD format have extra headers and metadata that means you can't
just dd it to the raw device?

Warner

On Fri, Jul 28, 2023 at 8:09 AM Paul Koning via cctalk <
cctalk@classiccmp.org> wrote:

> If you want to copy raw floppy image files to the device, a simple "dd"
> command will serve, if you first use fdparm to set /dev/fd1 to 10 sectors
> per track.
>
> paul
>
> > On Jul 28, 2023, at 8:04 AM, Hans-Ulrich Hölscher via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > Is it possible that there is a Linux version of ImageDisk?
> > I found a signature "IMD Linux 0.19" in the P/OS images from
> > ftp://computermuseum.informatik.uni-stuttgart.de/dec/pro3xx
> > If so, could you please provide a source or link for the said software?
> > Thanks a lot!
> >
> > Ulli
>
>

[cctalk] Re: Restoring Ultrix-32m 1.2 Floppies

[Warner Losh via cctalk]

On Mon, Jul 17, 2023, 3:34 PM Chuck Guzis via cctalk 
wrote:

> On 7/17/23 11:53, Ethan Dicks via cctalk wrote:
>
> > Chuck Dickman's algorithm is in lbn2rx50.c
> >
> > #define RX50_TRACKS  80
> > #define RX50_SECTORS 10
> >
> > int interleave[] = { 0, 2, 4, 6, 8, 1, 3, 5, 7, 9 };
> >
> > track = lbn/RX50_SECTORS;
> > track = (track + 1)%RX50_TRACKS;
> >
> > sector = lbn%RX50_SECTORS;
> > sector = (interleave[sector] + 2*(track - 1) +
> RX50_SECTORS)%RX50_SECTORS;
>
> Depends on the application.  Files-11 RX50 encoding is a bit stranger,
> with Track 79 mapped to physical track 0.
>
> I can pass my algorithm along, if anyone is interested.
>
> On the other hand, DECMate II and Rainbow use sector interleave but not
> track skew.
>
> If anything can be said about DEC, they were consistent in their
> inconsistency.
>

Yup. The Rainbow's track 0 and 1 were not interleaved to make the boot
loader easier... I think the decmate did yhe same but with different
tracks...

The rainbow also had a cool partitioning format that looked like it was
some general thing, but I never saw it elsewhere or have found an
electronic copy of the printed docs I pulled off dec's tops20 support
machine from the LSG in the late 80s

Warner

--Chuck
>
>
>
>

[cctalk] Re: Restoring Ultrix-32m 1.2 Floppies

[Warner Losh via cctalk]

On Mon, Jul 17, 2023, 12:42 PM Henry Bent via cctalk 
wrote:

> On Mon, 17 Jul 2023 at 13:06, Henry Bent  wrote:
>
> > On Mon, 17 Jul 2023 at 12:59, Ethan Dicks via cctalk <
> > cctalk@classiccmp.org> wrote:
> >
> >>
> >> > From: http://www.chdickman.com/pdp11/pro380.txt
> >> >
> >> > "The RX50 floppy starts at track 1. Track 0 is logically placed after
> >> > track 79. The sectors are interleaved 1, 3, 5, 7, 9, 0, 2, 4, 6, 8,
> >> > 10. The track shift and interleave must be taken into account when
> >> > moving disks between real PDP-11 and emulators."
> >>
> >> I have had good luck with a secfor convolver from the same page as this
> >> comment:
> >>
> >> http://www.chdickman.com/pdp11/lbn2rx50.c
> >>
> >> It will go both ways, to and from physical block order and logical block
> >> order.
> >>
> >
> > That seems to have worked perfectly.  Thank you for the utility and the
> > explanation.  Now off to working on the next steps!
> >
> > -Henry
> >
>
> A brief follow-up on this: After lots of (virtual) disk-swapping I was able
> to upgrade an existing 1.0 system but was not able to install a 1.2 system
> from scratch.  It seems that there is some sort of bootloader issue with a
> clean install, which I suspect might be a SIMH problem and I will follow up
> there after some more investigation.
>
> I truly feel for the folks who had to do this at the time, using 38
> floppies on a MicroVAX I.  The installer does give time estimates for
> certain milestones so that you could go and get a coffee or whatever.
> "Configuring vmunix, this takes about 30 minutes" is certainly indicative
> of the relative speed of the machine at the time.  Also there is an
> indication that there was a tape distribution but so far that has not
> surfaced.  I'm not even sure what medium that would have been - RC25?
>

Doing a VMS install, twice, on a microvax ii is what convinced the powers
that be to get a tk50... and an eagle 400mb drive... or at least put them
over the edge to proposing work that got the upgrade funded... iirc... The
VMS install was on a crazy number of floppies, if you counted all the
layered products and third party packages...

Warner

>

[cctalk] Re: Restoring Ultrix-32m 1.2 Floppies

[Warner Losh via cctalk]

On Mon, Jul 17, 2023, 10:59 AM Ethan Dicks via cctalk 
wrote:

> On Mon, Jul 17, 2023 at 12:48 PM Ethan Dicks 
> wrote:
> > On Mon, Jul 17, 2023 at 12:28 PM Henry Bent via cctalk
> > > I'm almost thoroughly unfamiliar with IMD - is there some obvious
> > > extraction/conversion option that I am missing here?
>
> As mentioned previously, yes.  There's an additional step that has to
> happen to any direct imaging of RX50 disks.  John Wilson's PUTR
> happens to do this convolution internally.
>
> If you desire is to snapshot physical media for rewriting later, IMD
> is excellent.  If you want logical-block-order files for simh, you
> need one more step (keep reading).
>
> >  Were these disks actually imaged correctly?  I would appreciate any
> suggestions.
>
> Yes they were.
>
> > From: http://www.chdickman.com/pdp11/pro380.txt
> >
> > "The RX50 floppy starts at track 1. Track 0 is logically placed after
> > track 79. The sectors are interleaved 1, 3, 5, 7, 9, 0, 2, 4, 6, 8,
> > 10. The track shift and interleave must be taken into account when
> > moving disks between real PDP-11 and emulators."
>
> I have had good luck with a secfor convolver from the same page as this
> comment:
>
> http://www.chdickman.com/pdp11/lbn2rx50.c
>
> It will go both ways, to and from physical block order and logical block
> order.
>

I've encountered this with Rainbow disks. I have a logical to phys
conversion program.
Also when i wrote the impdrive driver for the rainbow: you have to do the
unmapping
the Z80 code would do to make the 3.5" 720k floppy work in the Rainbow.

The physical sectors are numbered 1-10 on the drive (maybe past track 0 and
1). And
it is 1-10, there is no sector 0. These sectors refer to the logical
sectors 1, 3, 5, 7, 9, 2, 4,
6, 8 ,10. My program filters the 'physical' disk into a 'logical' oneso
that mtools can read
the FAT contained on my MS-DOS disks. On the Rainbow, at least, the WD
floppy controller
didn't mess with the sectors, so the interleave was done at the lowest
levels of whatever
OS' floppy driver.

Chances are quite good that there's a mismatch somewhere. If you always
read in one way and
write in that same way, it works (eg, both ends agree). Sometimes you need
to convert from one
to the other, which I always have to do via trial and error.

For Venix, there was  a different interleave (because of course there is),
so there may be some
experimenting that's needed. But since it is Unix, I suspect Ultrix may
have its own interleave,
but who knows. I've not looked at the source.

I believe I've uploaded these to github, but can't find them at the moment.
I can look if people
want. This may be all that's needed. It's been handy for both DOS and Venix
disks I've had to
decode.

Warner

>

[cctalk] Re: 10 types of people

[Warner Losh via cctalk]

On Mon, Jul 17, 2023, 8:51 AM Paul Koning via cctalk 
wrote:

> Seen on the GCC bugzilla:
>
> "actually, there are 10 types of people: those who understand ternary,
> those who dont, and those who thought this was going to be a binary joke"
>

I almost didn't open this... but I'm glad I did... though those sets aren't
completely disjoint... otherwise I neither understand nor don't understand
ternary :)

Warner

:-)
>
> paul
>
>

[cctalk] How to archive floppies

[Warner Losh via cctalk]

OK. I have about 500 DEC Ranibow floppy images that I've ripped over the
years.

I also have a number of .td0 images as well as other oddballs.

Other than Lotus 123 needing to have funky sectors on one of its bigger
tracks for copy protection, I think having the raw images suffice.

I have some disks that I have multiple copies of (MS-DOS, CP/M, Winchester
Utilities, DEC Rainbow diagnostics etc).I have a few copies of some
software packages. I have a few disks that are clearly personal. And some
of the variations of MS-DOS have different patches applied by various
install programs (or debug scripts published in different trade rags of the
time). And at least one has a special driver installed that overwrites the
DEC Winchester for things like Univation).

So, what I'd like to do is to is somehow organize all this. I wrote some
software to extract files from the filesystem.So I'd like to have a
separate copy of the expanded files.

Lots of moving parts for 40-year-old floppies. I'm struggling with how to
organize all this, how to keep track of this, and how to allow others to
contribute their disk images and allow things to be studied and run. I'd
like to keep the raw images (to mine them for drivers like the univation
one I discovered). I'd like to keep the busted apart files to access them
more easily, etc.

Is there some book, website, paper, etc that I can use to to help me
organize all this so I can share it with others? Is this even the right
place to ask? There's got to be several people that have solved this issue
before

Warner

[cctalk] Re: Shot In the Dark: Compaq System Manager Facility

[Warner Losh via cctalk]

I have

compaq-system-config-us-proliant-3000-333.disk1.gz
compaq-system-config-us-proliant-3000-333.disk2.gz
compaq-system-config-us-proliant-3000-333.disk3.gz
compaq-system-config-us-proliant-3000-333.disk4.gz

In my collection that I think I used to configure a Proliant 3000 with EISA
bus.

is that useful?

Warner

On Sat, Jul 15, 2023 at 5:43 PM Ali via cctalk 
wrote:

> Really long shot, and I have asked here before without much luck, but
> anyone
> have a copy of the Compaq System Manager Facility 1.10 or 1.11 (or any
> version for that matter). This would have been released in 1994/95 time
> frame and is necessary for the use of the Compaq Server Manager/R EISA
> board. This is a very early EISA RILO board for the System Pro and Proliant
> line of servers. Please note this is not the same as the System Management
> Agents nor the Insight Manager. TIA!
>
> -Ali
>
>
>
>

[cctalk] Re: 1974 No Name Terminal

[Warner Losh via cctalk]

On Thu, Jul 6, 2023, 8:41 PM Mike Stein via cctalk 
wrote:

> Conrac mainly made CRT monitor assemblies, so the actual terminal was quite
> possibly made by someone else.
>
> It looks vaguely familiar; I'm surprised no one's recognized it.
>

Yea. Looks vaguely SABER like, but my only experience with them is airline
tickets an eon ago... but the screen looks all wrong...

Warner

m
>
> On Thu, Jul 6, 2023 at 6:13 PM Brad H via cctalk 
> wrote:
>
> > Thanks Rod!
> >
> > I discovered an immediate problem I hadn't caught before.. two of the
> > trimmer resistors had actually been broken right off two of their legs..
> so
> > that may account for strange/missing voltages.   They are a CONRAC part
> > 928237.  The CRT is CONRAC too, but I still don't think this is a CONRAC
> > terminal.  Anyway, I only found one source for the exact resistor, an
> > aerospace company, and they want $80 per unit (I think they just want me
> to
> > go away).
> >
> > So far in testing I haven't found any shorts.  My main worry is the PSU
> > sending incorrect voltages to wrong place.  In addition to the broken
> > resistors I also discovered some broken solder joints on the PSU PCB..
> > those at least are repaired.  I'm trying to figure out the resistance the
> > two resistors were set to so I can put a replacement in with same,
> > hopefully that gets me close to what should be there.
> >
> > Brad
> >
> > -Original Message-
> > From: Rod Smallwood via cctalk 
> > Sent: Wednesday, July 5, 2023 8:48 AM
> > To: Douglas Taylor via cctalk 
> > Cc: Rod Smallwood 
> > Subject: [cctalk] Re: 1974 No Name Terminal
> >
> > I worked on VDU's as an engineer in the UK before joining DEC to sell
> > volume VT100's in 1975
> >
> > There's a mention of block on one of the cards so a block mode terminal.
> >
> > That means enter data and press a key to send the lot.
> >
> > The card cage could mean its emulating something.
> >
> > I'd test as many capacitors as possible. PSU first and replace as
> required.
> >
> > Run PSU and check voltages.
> >
> >   Check each board for power rail to ground shorts.
> >
> >   If ok give each board +5v on its own and see if the TTL is alive.
> >
> > If theres a clock gen start there (look for a crystal can)
> >
> >   Loads of fans might indicate an industrial environment
> >
> >At this age some TTL will have failed plus capacitors.
> >
> >   Rod Smallwood
> >
> >
> > On 05/07/2023 16:28, Douglas Taylor via cctalk wrote:
> > > At first glance it reminded me of the Hazeltine 1000, I owned one in
> > > the early 1980's.  Brutally simple terminals, I remember getting a ROM
> > > from Jameco which allowed the terminal to display lowercase letters.
> > > Pure luxury.
> > > Doug
> > >
> > > On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
> > >> Hi there - not sure how much overlap there is with vcfed's forum, but
> > >> thought I would reach out here in case.  I have a terminal from 1974
> > >> (based on date codes I've found on the motherboard).  I'm unable to
> > >> determine manufacturer and that would be handy for diagnostic
> > >> purposes. The terminal casing is made out of foam, and although there
> > >> are some serial numbers stamped around, nothing really lines up.  The
> > >> fans inside have zero dust or dirt, so I'm thinking this may not have
> > >> seen much use, or may be a prototype or pilot for something.  It does
> > >> have RS232 capability. Interestingly the screen is set down below the
> > >> keyboard so that only half of it is visible.
> > >>
> > >>
> > >> My main issue right now is the PSU - I am trying to determine if I'm
> > >> safe to attempt powering up the board (the PSU so far seems to be ok,
> > >> although some voltages on a couple of pins are mysterious).
> > >>
> > >>
> > >> Anyway, on the extremely off chance anyone has ever seen one of these
> > >> or something like it.. any tips would be appreciated. If I can find a
> > >> manual I'll feel a lot safer about turning it on.
> > >>
> > >>
> > >> Some pics here:
> > >> https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2
> > >> Qkj?usp
> > >>
> > >> =sharing
> > >>
> > >>
> > >> Brad
> > >>
> > >> b...@techtimetraveller.com
> > >>
> > >>
> > >
> >
> >
>

[cctalk] Re: Any RSX-11 fans able to identify file types?

[Warner Losh via cctalk]

On Sun, Jun 25, 2023, 1:44 PM Wayne S via cctalk 
wrote:

> The file list says they were created in the 1986 time frame.
> So what Dec systems were running around then that required rsx11 ?
>

Chances are good if it is 86, then there'd be a pro port... these were
reported extensively in the trade rags of the day, but sales weren't so it
may be hard to say. Also, there were a few accounting packages that were
also on cp/m and the PC so that might help...

Though connecting press reports to these files might be hard...

Warner


Sent from my iPhone
>
> On Jun 25, 2023, at 12:39, Wayne S  wrote:
>
>  Pretty hard to tell from just the file names what app created them and
> looking for (for example) .msl files sends you down different paths, like
> visual studio ( probably not), ImageMagick Scripting Language File,
> MAINSAIL Source Code, and ProWORX Nxt MSL are all apps that create .msl
>
> Any more info you can shed on what the industry is that the customer does?
> Is it geographic mapping or some kind of science processing?
>
>
> Sent from my iPhone
>
> On Jun 25, 2023, at 12:16, Tomasz Rola via cctalk 
> wrote:
>
> On Sat, Jun 24, 2023 at 04:39:01PM -0700, Chuck Guzis via cctalk wrote:
> On 6/24/23 12:38, Wayne S wrote:
> Chuck, why not post the catalog snd we’ll all take a look?
> Power of the internet!
>
> Okay, I guess that's okay.   Here's the data from the MFD:
>
> https://icedrive.net/s/Q56ZY2Sv4g62Gi9vZ9jzNQ2CD6Bu
>
> Since this is customer data, I can't publish the contents of the files
> themselves.
>
> If you have those files accessible from some Unix-like OS, then you
> can:
>
> strings < theXfile.x | less
>
> Sometimes also:
>
> hexdump -C < theXfile.x | less
>
> Or, to avoid the risk of fu-ups if you put "<" in bad direction:
>
> cat theXfile.x | strings | less
>
> It may reveal a bit about the insides of the file, for example in case
> of sqlite database there would probably be a tables description.
>
> Also, comparing
>
> cat theXfile.x | strings | wc -c
> cat theXfile.x | wc -c
>
> would givw some idea of how much of the file is text and how much of
> it is something else.
>
> All those tricks assume that files are uncompressed, of course.
>
> HTH
>
> --
> Regards,
> Tomasz Rola
>
> --
> ** A C programmer asked whether computer had Buddha's nature.  **
> ** As the answer, master did "rm -rif" on the programmer's home**
> ** directory. And then the C programmer became enlightened...  **
> ** **
> ** Tomasz Rola  mailto:tomasz_r...@bigfoot.com **
>

[cctalk] Floppy recovery

[Warner Losh via cctalk]

OK. I have just read in a bunch of Rainbow disks. Most of them read fine on
the first, second or third try. Some have a sector or three amiss (I've not
yet checked to see if those sectors are mapped to the filesystem or not).
Some appear to be 'unformatted' though sometimes they read with errors.
These disks have what appears to be some kind of grime/mold/??? on their
surface.

Is there a good way to read these diskettes? To clean the grime off and
allow the floppy to spin (they all are super loud)...

At the rate things are going, there will be 5-10 of these...

Warner

[cctalk] Re: How much memory?

[Warner Losh via cctalk]

On Sat, Jun 17, 2023, 10:38 AM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

>
> On 6/17/2023 10:42 AM, Henry Bent via cctalk wrote:
> > On Sat, 17 Jun 2023 at 10:31, Paul Koning via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> >
> >> BSD 2.11 had TCP/IP.
> >>
> > Later versions of 2.9BSD had TCP/IP though the hardware support was
> pretty
> > limited.  And you could probably use the present tense for 2.11BSD, it's
> > still getting patches.
> >
>
> Ultrix-11, which was DEC version of Version 7 had TCP/IP.  I use it all
> the time.
>

I believe the Ultrix 11 had the bsd 2.10 tcp code in it... it had a lot of
Berkeley code in it...

Warner

bill
>
>
>

[cctalk] Re: How much memory?

[Warner Losh via cctalk]

On Fri, Jun 16, 2023 at 6:04 PM ben via cctalk 
wrote:

> On 2023-06-16 4:56 p.m., Chuck Guzis via cctalk wrote:
> > On 6/16/23 12:48, ben via cctalk wrote:
> >
> >> What cpu?
> >> Minix was 16 bit code only. I suspect 16 bit code here as well.
> >> Remember 32 bit code is 2x the size of 16 bit stuff.
> >
> > 32-bit, I'm afraid.   To quote:
> >
> > WHAT IS LINUX?
> >
> >Linux is a Unix clone for 386/486-based PCs written from scratch by
> >Linus Torvalds with assistance from a loosely-knit team of hackers
> >across the Net.  It aims towards POSIX compliance.
> >
> >It has all the features you would expect in a modern fully-fledged
> >Unix, including true multitasking, virtual memory, shared libraries,
> >demand loading, shared copy-on-write executables, proper memory
> >management and TCP/IP networking.
> >
> >It is distributed under the GNU General Public License - see the
> >accompanying COPYING file for more details.
> >
> > --Chuck
> >
>
> Was that quote written for version #1.
> At risk of being a troll, when did Unix (PDP 11) not have all the the
> above. Other than TCP/IP networking, I don't see any of above features
> desirable, as I feel a need for more real time operating systems.
>


The PDP-11 never had useful virtual memory, the 8k segment size was simply
too large to do anything other that interprocess protection and have a
separate address space per process. It never had a useful mmap, so it never
had useful shared libraries, it couldn't demand load binaries (they were
loaded entirely at startup), there was no copy-on-write sharing. Not sure
what 'proper memory management' meant, so can't comment on that

AT PDP-11 unix never had TCP/IP from AT, though an early NCP version
existed and BBN's TCP stack made V7 and newer have TCP. The BSD side had
TCP/IP, running in a "separate" process from the kernel (it ran in
supervisor mode, to get more address space out of the PDP-11 architecture
while sharing the data segments). 2.9 had TCP/IP, but it wasn't until 2.10
or 2.11 that it was really stable.

How many OS's are complete in design that you don't need to bypass
> the OS like MS DOS.
>

I've evaluated several router products, years ago, that just used Lnux or
FreeBSD to load an application that took over the machine...

Warner

[cctalk] Re: How much memory?

[Warner Losh via cctalk]

On Fri, Jun 16, 2023 at 1:49 PM ben via cctalk 
wrote:

> On 2023-06-16 1:40 p.m., Chuck Guzis via cctalk wrote:
> > On 6/16/23 12:02, ben via cctalk wrote:
> >
> >> Ken , Jobs and  Wozniak need their fair share.
> >> Graphics and file system buffers take up more
> >> space than you expect.
> >
> > I just transferred a DC150 tar tape.  Total (uncompressed) file size was
> > 11MB.  What was on it?  The complete source to Linux 1.0.
> >
> > --Chuck
> >
> What cpu?
> Minix was 16 bit code only. I suspect 16 bit code here as well.
> Remember 32 bit code is 2x the size of 16 bit stuff.
>

Linux never ran on 16-bit hardware, though weird pseudo-forks like ELKs
have.

And 32-bit source code tends to be about the same length as 16-bit source
code, at
least in C. Object code... can vary somewhat.  On Intel 32-bit code isn't
2x the size of
16-bit object code because the variable encoding generally encodes to the
same length.
The data will be bigger, especially addresses, and the 32-bit intel code
usually programs
the MMU, which 16-bit code can't really do (well, depending on how you rate
the 286
memory model).

Warner

[cctalk] Re: Did Bill Gates Really Say That?

[Warner Losh via cctalk]

On Wed, Jun 14, 2023, 12:22 PM Will Cooke via cctalk 
wrote:

>
>
> > On 06/14/2023 12:58 PM CDT Bill Degnan via cctalk 
> wrote:
> >
> > As far as the Bill Gates quote, I do remember reading an actual longer
> > quote somewhere (?), the context was lost from a larger paragraph if one
> > takes just the snippet statement IIRC.
> >
>
> Maybe the longer quote was "I never said no one will ever need more than
> 640K." ;)
>

There are two details that should be brought up. The quote is bogus, sure.
Gates did work to increase the limit (There are stories of him getting the
design changed from 512k to 640k, for example). He also has said that one
shouldn't avoid the pc because of that.. which is way different than "never
need" the quote uses... both of these are quite reasonable things...
especially since obe of the original expanded memory schemes came from
Microsoft in part...

Warner

[cctalk] Re: First non-IBM PC-DOS Compatible PC

[Warner Losh via cctalk]

On Wed, Jun 7, 2023 at 11:18 PM Yeechang Lee via cctalk <
cctalk@classiccmp.org> wrote:

> Warner Losh says:
> > The DEC Rainbow also hit these issues and needed its own custom
> > version of kermit...
>
> Yes, but DEC did not claim that Rainbow is fully PC compatible. Eagle and
> Seequa did.
>

True. It was some years later that we got code blue on the Rainbow to run
IBM stuff Except
even that wasn't completely there...

And Yes, it was one reason I got it: it could have more memory than the PC,
and that came
in handy for some of the stuff I wound up doing with mine...

Warner

[cctalk] Re: First non-IBM PC-DOS Compatible PC

[Warner Losh via cctalk]

On Wed, Jun 7, 2023, 1:59 PM Yeechang Lee via cctalk 
wrote:

> db says:
> > As we were painfully made aware when people tried to run comm
> > programs and they didn't work because we used the Z8530 to get dual
> > serial ports.
>
> Hyperion was not alone in having trouble with comm ports. Columbia
> University (my alma mater) reported in January 1984 that unmodified Kermit
> ran on Compaq and Columbia PCs, but Eagle and Seequa needed custom code.
>
> I highly recommend the Kermit mailing list archives <
> http://www.columbia.edu/kermit/ftp/e/info-kermit.txt>; it contains
> massive amounts of information for anyone interested in classic computers.
>

The DEC Rainbow also hit these issues and needed its own custom version of
kermit...

Warner


-- 
> geo:37.78,-122.416667
>

[cctalk] Re: ST-251 Data Recovery for Glenside Color Computer Club (GCCC)

[Warner Losh via cctalk]

On Tue, May 16, 2023, 8:30 PM Fred Cisin via cctalk 
wrote:

> Well, that would be "spot on", as the formatted capacity of an ST-251 was
> 40 Megabytes.
>
> When used with MS-DOS, prior to

MS-DOS 3.31, it would be partitioned as
> two 20MB, or as a 32MB plus an 8MB.
> (V3.31 was the first version of MS-DOS to support a partition larger than
> 32MB)
>


That's how I used it on my DEC Rainbow under MS-DOS 2.11 and later 3.10b.
And recently under venix...

Warner



On Tue, 16 May 2023, Mike Katz wrote:
>
> > The biggest drive I remember seeing on OS/9 was 20MB or 40MB.  I
> > don't remember the File Allocation Table size or format.
> >
> > On 5/16/2023 7:14 PM, Fred Cisin via cctalk wrote:
> >> On Tue, 16 May 2023, Mike Katz via cctalk wrote:
> >>> Most likely there was some kind of driver for the CoCo that
> >>> converted the ST-251 into smaller logical drives for the CoCo
> >>> Operating system.
> >>
> >> One fellow, who used to be involved in Cocos, recalls one or more
> >> systems that handled it by MANY "virtual floppies" on the drive.
> >>
> >> I think that OS-9 may have had support for "big" drives.
> >>
> >> --
> >> Grumpy Ol' Fred ci...@xenosoft.com

[cctalk] Re: Using Teledisk 2.16 to read old RX50 images

[Warner Losh via cctalk]

On Sun, May 14, 2023, 7:47 AM Chris Zach via cctalk 
wrote:

> Hi!
>
> Well, after a good bit of work I have finally gotten my Compaq XE4000 up
> and running with Windows 98, the BIOS all set, a new battery, and of
> course a 1.2mb 5.25 floppy that seems to be working.
>

I'd avoid teledisk.  I'd look at Dave Dunfield's ImageDisk. It produces
those img files directly.  It's linked from
http://dunfield.classiccmp.org/img/index.htm

I'd now like to start sucking the rare images I have here on RX50 into a
> TD0 format which can be converted to a .IMG format which can then be
> used on the mighty GoTek's to allow people to run such operating systems
> as:
>
> Micro RSTS 2.1
> Micro RSX (I forget the exact version)
> Micro-11 Maint disks
> Ultrix 11 Version 2.0 (all 30 disks)
>

Oh, these are interesting.

http://www.bitsavers.org/bits/DEC/pdp11/floppyimages/rx50/

Has some interesting goodies too, but none of these excrpt maybe yhe Micro
RSTS stuff. Maybe if you get them imaged, you could send them to Al.

If you are in Denver by chance, I'd be happy to help image these too.

Warner

Before I start popping these in I have a question: I just did a test
> using an XXDP floppy and the message I got included
> Single sided, double density
> Interleave 1:1
> Sector Size is 512
>
> And then for each track from 1 to 82 (?) it said
> "Data, No ID adding sector 110"
>
> Is this right? Something else I might need to do for reading RX50's?
>



Thanks!
> CZ
>

[cctalk] Re: NRAO Data tapes

[Warner Losh via cctalk]

On Tue, May 9, 2023, 9:47 PM Mark Linimon via cctalk 
wrote:

> I wonder if those date to the first time I visited, where the PDP-11s
> were still installed :-)
>
> Are there still T-shirts available?  Mine from that trip is trash :-)
>

The pdp-11s were Gove by the time I got to tech in 85 I think


mcl
>

[cctalk] Re: The World Wide Web

[Warner Losh via cctalk]

On Thu, May 4, 2023, 6:59 AM geneb via cctalk  wrote:

> On Wed, 3 May 2023, Mike Katz via cctalk wrote:
>
> > Don't forget fidonet (a network of bulletin board systems).
> >
> FidoNet is still a thing too.  I'm the NC of Net 138. (which sadly, is now
> just myself and a couple of other nodes.)
>

Sadly, the node lists are super out of date...

Warner

g.
>
> --
> Proud owner of F-15C 80-0007
> http://www.f15sim.com - The only one of its kind.
> http://www.diy-cockpits.org/coll - Go Collimated or Go Home.
> Some people collect things for a hobby.  Geeks collect hobbies.
>
> ScarletDME - The red hot Data Management Environment
> A Multi-Value database for the masses, not the classes.
> http://scarlet.deltasoft.com - Get it _today_!
>

[cctalk] Re: flipchip cleaning and pin corrosion inhibition

[Warner Losh via cctalk]

On Sun, Apr 23, 2023, 3:56 PM W2HX via cctalk  wrote:

> I might be concerned about putting carbon comp resistors in the dishwasher
> as they are hygroscopic.
>
> From an Ohmite datasheet:
> https://www.mouser.com/datasheet/2/303/res_od_of_oa-180619.pdf
>
> "Carbon composition resistors are highly hygroscopic and
> changes in resistance value can occur if too much moisture is
> absorbed. For this reason, it is recommended not to use water
> or water-soluble solvents to clean these components. Alcohol
> or hydrocarbon solvents are recommended for rinsing."
>

Years ago, I worked at a place that made their own boards in house. They
had a dishwasher for that. They had valve on it to disconnect the water
supply so they could fill it with alcohol or similar for special jobs.

Warner

73 Eugene W2HX
> Subscribe to my Youtube Channel: https://www.youtube.com/@w2hx/videos
>
>
> -Original Message-
> From: KenUnix via cctalk 
> Sent: Sunday, April 23, 2023 5:53 PM
> To: General Discussion: On-Topic and Off-Topic Posts <
> cctalk@classiccmp.org>
> Cc: KenUnix 
> Subject: [cctalk] Re: flipchip cleaning and pin corrosion inhibition
>
> Pete,
>
> Did the 8E have core or solid state memory?
>
> Ken
>
>
> On Sun, Apr 23, 2023 at 4:06 PM Pete Turnbull via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > On 23/04/2023 17:54, Fritz Mueller via cctalk wrote:
> >
> > > I’ve been eying the dishwasher, for the subset of flip chips that
> > > that
> > are just DIP logic, carbon comp resistors, and ceramic bypass caps,
> > anyway.   But I haven’t been brave enough to try that yet...  Most of the
> > logic here has date codes to ’68 or ’69, so I’m inclined to treat it
> > gently.  Any suggestions for approaches to clean this up?
> >
> > I've used the dishwasher on a collection of PDP-8/E boards with success.
> >   Avoid the hot drying cycle, and don't use a harsh dishwasher
> > detergent; some are quite caustic.
> >
> > --
> > Pete
> > Pete Turnbull
> >
> >
>
> --
> End of line
> JOB TERMINATED Okey Dokey
>

[cctalk] Re: ATA-3 50-pin IDE

[Warner Losh via cctalk]

On Sun, Mar 26, 2023 at 10:20 PM Paul Berger via cctalk <
cctalk@classiccmp.org> wrote:

> I have seen lots of laptop drives that would fit a 50 pin connector that
> is about 2mm pitch  Looking at the back of the drive from the left there
> are 44 pins in a group then 2 pins missing and the remaining 4 are for
> selecting master and slave.
>

https://www.unitechelectronics.com/ide44pinout.gif which shows 44 pins +
the '6' extra slots
for cable select and keying. These are often called the '44 pin'
interface...

Warner


> Paul.
>
> On 2023-03-26 4:33 p.m., Steve Lewis via cctalk wrote:
> > Is anyone familiar with the 50-pin IDE interface, which I think is called
> > ATA-3?  It is from around 1997-2002.   Normally IDE is 40-pin, or in
> > laptops might be a 44-pin.
> >
> > But in a COMPAQ Presario 1220, I've come across its hard drive that is
> > using this 50-pin interface (two rows of 25-pin that are quite
> > small/tightly spaced - moreso than even PCMCIA).
> >
> > I believe it is different (electrically) than the 1.8" 50-pin
> interface.  I
> > ordered a CF-to-50-pin adapter that is intended for those 1.8" drives,
> and
> > it won't work on this ATA-2 port (system won't boot with it inserted).
> > However, all my CF cards are larger than 2GB - so I'm not sure if that
> was
> > the issue (don't think so, I think even with 8GB or larger it would still
> > at least try to boot).
> >
> >
> > The 2GB drive in this Presario (with the "weird' 50-pin IDE) contains
> > Windows ME and Office 2000.  That's cute, but I'm not so interested in
> that
> > - I was hoping to image that drive for archive, then install something
> else
> > (OS2).  But I can't find any "ATA-3 to normal 40-pin IDE" adapter.
> >
> > I think the "6 extra pins" on this 50-pin (relative to normal 44-pin
> laptop
> > drives of those days) -- 2 of those pins (5-6) aren't used (maybe a kind
> of
> > key) and the 4 others (1-4) are vendor specific.  So I may just be out of
> > luck here in upgrading or replacing this drive with a more modern
> > solution.  But wanted to run it by the crew here before giving up.
> >
> > Thanks,
> >
> > -Steve / v*
>

[cctalk] Re: ATA-3 50-pin IDE

[Warner Losh via cctalk]

50 pin is usually SCSI I've never heard of an Ata standard that did
that... 44 pin laptop was just 40 pin + power (and maybe cable select, I
forget).

There was an 80 pin cable standard, but that used 40 pin headers and
special connectors to do primary/secondary better/faster especially for
dma...

So if it is ATA, I'm very curious to see what I missed back in the 90s...

Warner

On Sun, Mar 26, 2023, 9:33 PM Steve Lewis via cctalk 
wrote:

> Is anyone familiar with the 50-pin IDE interface, which I think is called
> ATA-3?  It is from around 1997-2002.   Normally IDE is 40-pin, or in
> laptops might be a 44-pin.
>
> But in a COMPAQ Presario 1220, I've come across its hard drive that is
> using this 50-pin interface (two rows of 25-pin that are quite
> small/tightly spaced - moreso than even PCMCIA).
>
> I believe it is different (electrically) than the 1.8" 50-pin interface.  I
> ordered a CF-to-50-pin adapter that is intended for those 1.8" drives, and
> it won't work on this ATA-2 port (system won't boot with it inserted).
> However, all my CF cards are larger than 2GB - so I'm not sure if that was
> the issue (don't think so, I think even with 8GB or larger it would still
> at least try to boot).
>
>
> The 2GB drive in this Presario (with the "weird' 50-pin IDE) contains
> Windows ME and Office 2000.  That's cute, but I'm not so interested in that
> - I was hoping to image that drive for archive, then install something else
> (OS2).  But I can't find any "ATA-3 to normal 40-pin IDE" adapter.
>
> I think the "6 extra pins" on this 50-pin (relative to normal 44-pin laptop
> drives of those days) -- 2 of those pins (5-6) aren't used (maybe a kind of
> key) and the 4 others (1-4) are vendor specific.  So I may just be out of
> luck here in upgrading or replacing this drive with a more modern
> solution.  But wanted to run it by the crew here before giving up.
>
> Thanks,
>
> -Steve / v*
>

[cctalk] Re: Using Flashfloppies on Professional 350 and 380--SOLVED

[Warner Losh via cctalk]

This is very cool! Glad to see you got it working...

On Sat, Mar 4, 2023 at 9:06 PM Chris Zach via cctalk 
wrote:

> Ok, after banging my head against the wall for awhile this evening it
> looks like I have two flashfloppy drives working on my Pro/380. Well
> enough to boot from and install 3.2 options.
>
> The keys are these:
> 1) Use a flat 34 pin ribbon cable with three plugs in a straight line. I
> tried using one with the traditional flip, got frustrated at the extra
> complexity, and reterminated it as straight through all the way.
>
> 2) Set one drive to unit 0 (J2 installed) and the second to unit 1 (J3
> installed)
>

Yea, that's how the two floppy setups on the DEC Rainbow were done.
Flipped cables only were a IBM-PC thing at first, though others started
using them later to emulate the PC... The few CP/M machines I've played
with were more like the Rainbow than the IBM-PC, but there were so
many CP/M machines I might have missed it...


> 3) This is the kicker: RX50's are Shugart drives. You have to go into
> the configuration and set the drives to Shugart. IBMPC doesn't work
> properly with the disk ready and disk swap signal, I stumbled on this
> when I found that flipping the disk image while it was seeking produced
> a brief access. Hah.
>

Yes. Pin 34 is READY, not CHANGE, and it has to come ready for the
controller to like the drive. I managed to get the GoTek working with
this config, but I did this for a single drive on my Rainbow. Since I
have the MFM emulator, I've only dabbled with the GoTek.


> 4) I set the ff.cfg also to read only to avoid stepping on the images by
> accident.
>
> So far it seems to be working, saw both drives in the file manager (I
> had built a minimum system with the floppies I had) and now I'm
> reformatting the RD53 drive and doing a full install. Should be as
> simple as turning the knob and hitting resume.
>

Nice!


> Thanks to Bjoren for letting me know it kind of worked for him years ago
> which gave me the knowledge that it could work. One issue I can see is
> that since both "drives" use the same head, stupid software could assume
> that since drive 0 was seeked to track 30 then drive 1 should be at
> track 30 and thus no need to change tracks. So far I haven't seen this
> happen, but we shall see.
>

I've not seen this assumption in practice. Part of the reason is that,
I was told years ago, was because many DEC Engineers had two separate
drives instead of the RX-50 in their systems, so errors like this would be
caught and fixed. I never encountered any when I ran my DEC Rainbow
with two TEAC FD-55F drives in either MS-DOS or CP/M. That doesn't
mean they don't exist, but it's been more of hypothetical than a common
thing. I'd love to see if you stumbled over this...

Warner

[cctalk] Re: Need a 1.2mb 5.25 floppy

[Warner Losh via cctalk]

On Mon, Feb 27, 2023 at 11:10 AM Christian Corti via cctalk <
cctalk@classiccmp.org> wrote:

> On Mon, 27 Feb 2023, Warner Losh wrote:
> > You should be using QD floppies, but those are rare. DD floppies from
> > later than 1985 though work just fine (discovered empirically while a
>
> Are they? I guess that I have at least as many QD floppies as DD, if not
> even more. :-)
>

I'd guess at least as many HD floppies, likely way more. QD was a pretty odd
duck, and any


> > However, in a PC, to write these diskettes, you need a 1.2M drive. While
> > there is a couple of TEAC drives (55FR I think) that do 80-tracks at the
> > DD/QD RPM and data rates, things get fussy putting them into PCs. And
> > last time I looked they were 5x the price of ye-olde-generic 1.2M floppy
> > drive. As long as it's formatted at the right density/rpm rates, it's
> > fine. And RX50.SYS, if memory serves, does all that right.
>
> When giving an advise, it should be as correct as possible ;-))
> So no, you don't need a "1.2M drive" (i.e. high density). You just need a
> 96 tpi drive. And the drive is totally (well, almost) ignorant of the data
> rate. It is just spinning the media at a specific velocity (300 or 360
> rpm). When using a 300 rpm drive, you need a 250 kHz data rate for DD (QD
> is the same, it's just a marketing name for 96 tpi DD). With 360 rpm you
> need a 300 kHz data rate. It only gets a little bit complicated if you
> jumper a high-density drive for dual-speed mode (300 rpm if DD, 360 rpm if
> HD).
>

Correct. You don't need a 1.2M drive. That's true. However, getting the
96tpi QD
300prm 250kHz drives are a lot harder these days than finding an old 1.2M
drive.
I recently looked for the TEAC 55FR drives that I used back in the day, and
could
not find them at all. Found plenty of other TEAC 55xx drives that were all
either
'360k' or '1.2M' drives. So it was more of a practical bit of advice, than
an absolute
requirement...

While several of the newer drives do allow dual speed operations, the floppy
cables for the RX-50 drive don't have the necessary signals to switch them.
IDrives
used a transistor to switch the signals properly for these drives. I opted
to use
drives that didn't need this signal. For 3.5" drives, there weren't any
hacks
needed because that signal was ignored by most of the drives.

I rarely used them on a PC back in the day, so I'll defer to others on that.


> > Using 3.5" drives in double density mode will work, but there's a cascade
> > of software issues you'll have to deal with. I booted my DEC Rainbow with
>
> It would be the same for a normal 5¼" double sided drive. IIRC the trick
> is to combine the RX50 specific drive selects to one drive select and one
> head select. The software should not know anything about this. Drive 0
> would be side 0, and drive 1 side 1.
>

The trick is just to use two double sided drives, the side select stuff is
there,
and you just need to jumper the drives to be ID0 and ID1 to get your A & B
drives. You have to use for this, though, drives that can do 300rpm at
250kHz
because that's what (at least the Rainbow) RX-50 controller puts out. I ran
this way for many years, though the software changes to MS-DOS were a bit
flakey for me, and I never found ones for CP/M.

I only got the 3.5" floppy drives that were the lower density to work,
since those
were also 300rpm/250kHz. I never got the high density ones to work since at
least the ones I looked at didn't have the density signal, nor density
jumpers.
Wrote a 'driver' for it called IMPDRIVE back in the day. Some 5.25" drives
would
work with it (like the TEAC 55FRs), but many would not. And my old FRs are
toast and I've not been able to find good replacements to try this again...

Warner

[cctalk] Re: Need a 1.2mb 5.25 floppy

[Warner Losh via cctalk]

On Mon, Feb 27, 2023 at 9:30 AM Chuck Guzis  wrote:

> On 2/27/23 06:50, Warner Losh wrote:
>
> > You should be using QD floppies, but those are rare. DD floppies from
> > later than
> > 1985 though work just fine (discovered empirically while  a poor college
> > student,
> > reconfirmed recently when I made all those Venix disks).
>
> Speaking from experience and consultations during the 1970s with
> engineers from Dysan (we were using 100 tpi drives), the only difference
> between QD and DD floppies is QA step--QD ones are usually verified at
> 96 or 100 tpi, the DD ones at 48 tpi.  The brown goo spread on the
> doughnut is exactly the same.
>

Prior to about 1984 or 85, the failure rate for DD floppies for me was
high enough that I splurged for the QD. After 84 or 85, I never had any
problems
using DD media. I suspect that yields must have gotten better, but maybe I
just had bad luck prior to going to college...


> If one purchased factory-formatted diskettes for a specific platform, of
> course the formatting would be different depending on the platform.
>

True. For the Rainbow I was always reformatting because nobody sold
pre-formatted Rainbow disks at a price that was sane.


> Similarly SS and DS diskettes are identical; early on, ones with
> verification errors on one side were "flipped" accordingly and sold as
> SS. As techniques improved, the only difference became the label.
>

I believe that..

Warner

[cctalk] Re: Need a 1.2mb 5.25 floppy

[Warner Losh via cctalk]

On Mon, Feb 27, 2023 at 12:06 AM Chuck Guzis via cctalk <
cctalk@classiccmp.org> wrote:

> On 2/26/23 16:42, Chris Zach via cctalk wrote:
> > Oi.
> >
> > So after finally getting things going I started copying the Pro/380 OS
> > files to a bunch of 1.2mb floppies. Great. However after a bit I started
> > getting errors, and found that the disks were getting gouges in the
> > tracks. Sure enough disassembly of my 1.2mb Teac showed that debris had
> > become embedded in the disk head and cleaning is not possible.
> >
> > Terrific. Tossing the drive, this is not the first time I have had this
> > problem with these disks so I am dumpstering all of the old floppies and
> > just bought 40 new ones in sealed boxes.
> >
> > However I'm now in need of a 1.2mb floppy drive. Anyone have a good
> > working spare that I can beg/borrow/buy in the MD area?
>
> I thought the Pro 300 series used RX-50 drives; i.e. 400K 96 tpi DD
> media.   So even with your 5.25" HD drive, you should be using DD
> ("360K") floppies.
>

You should be using QD floppies, but those are rare. DD floppies from later
than
1985 though work just fine (discovered empirically while  a poor college
student,
reconfirmed recently when I made all those Venix disks).

However, in a PC, to write these diskettes, you need a 1.2M drive. While
there is a couple of TEAC drives (55FR I think) that do 80-tracks at the
DD/QD
RPM and data rates, things get fussy putting them into PCs. And last time
I looked they were 5x the price of ye-olde-generic 1.2M floppy drive. As
long
as it's formatted at the right density/rpm rates, it's fine. And RX50.SYS,
if memory serves, does all that right.

Using 3.5" drives in double density mode will work, but there's a cascade
of software issues you'll have to deal with. I booted my DEC Rainbow with
these and some hacks from someone in the Jemez Mountains to do double
sided on MS-DOS (which reminds me, I have the hacks still, and they also
have a now lost-ish BIOS listing for 3.10b, so I should see if I can post
that for the few people still interested).I've never done it on a PRO
though.

I'm out in Colorado, or I'd happily give you one of my spares.

Warner

[cctalk] Re: Getting QRST files onto a floppy (sigh)

[Warner Losh via cctalk]

USB floopies are not general purpose devices. They have a fixed number of
formats that work, and the rest do not.

Warner

On Sun, Feb 26, 2023 at 2:44 PM Wayne S via cctalk 
wrote:

> Your troubles with USB floppy drives reinforces my own experiences. They
> seem to work okay in windows using a Microsoft written utility but not too
> well in dos or user written programs. It’s hit or miss as to if the program
> will see the usb floppy. However, using a builtin floppy always seems to
> work.
>
> Sent from my iPhone
>
> > On Feb 26, 2023, at 12:17, Chris Zach via cctalk 
> wrote:
> >
> > Hi Henry!
> >
> >>   You wanted a SETUP disk for a Deskpro/XE system, right?  Like SP1363
> >>   as listed here https://www.vogons.org/viewtopic.php?t=76542
> >>    ?  I was able to do
> >>   this in Dosbox-X no problem: mount the local directory with
> >>   sp1363.exe as C: or whatever, attach a disk image to A:, and then
> >>   let sp1363.exe create the disk image on A: .  You can then write the
> >>   raw disk image to a 1.44" floppy.
> >
> > Interesting. I was using DOSBOX, not DOSBOX-X. I tried downloading it,
> set the A: drive to be the USB a: drive, and it doesn't work. This time it
> bombs out with QRST transfer incomplete.
> >
> > So I restarted, copied one of the diagnostic floppy images I did have to
> a filename of xe.img, mounted it in dosbox-x with the imgmount a (filename)
> command, then ran QRST and it seems to have worked.
> >
> > So if you try to use a USB floppy it can't see it, but if you use an
> image file it can. I wonder if Dosbox sees the external floppy as a SCSI
> device, but when you do an imgmount it knows to use the real, crappy DMA
> based routines to access the image file.
> >
> > Off to copy the image file to the pi, then to the USB floppy, then maybe
> to get the XE running. Fascinating, and thank yoU!
> >
> > CZ
>

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Wed, Feb 1, 2023, 2:52 PM Paul Koning via cctalk 
wrote:

>
>
> > On Feb 1, 2023, at 3:20 PM, Fred Cisin via cctalk 
> wrote:
> >
> > On Wed, 1 Feb 2023, Ali via cctalk wrote:
> >> But does that matter? If the main purpose is to be able to refresh the
> data so it is readable does it matter that the data is not in the same
> block as long as it is readable?
> >
> > Ah, but most of that sort of memory has a finite number of cycles, and
> wears out due to use.
> > Testing it is heavy usage, and brings about an even earlier end of life.
> > Could we call that a "nosocomial" ("not so comical") deterioratoin :-?
>
> It's well known that flash memory (and NVRAM generally) has write limits.
> I don't know of any read limits.  Some other memories have write limits as
> well though they are far larger and generally far less known.  I think some
> of the phase change non-volatile memory types that seem to emerge from time
> to time -- FRAM for example -- have write limits.  Modern high density HDAs
> also do, I believe, because the heads actually come closer to the surface
> during write and as a result are more likely to touch the platter.
>
> But read limits?  I'm not sure about that.  What sort of numbers are we
> talking about?
>

Read disturb in NAND is a thing. However, it kicks in after millions or
hundreds of millions of page reads in a single EB. Most FTLs I've seen will
treat this like any other "too many bits in error" read when it happens.
Some drives keep track and do things with voltage thresholds to compensate.
A few try to proactively garbage collect, though the benefits of that are
slim to nil for most workloads.

Warner

P.S. some QLC NAND has worse read disturb, but it's only 100x worse. It can
come up for high volume applications but not for simple archival reading.

If all else fails there's core memory, which as far as I remember is pretty
> much unlimited for both read and write.
>
> paul
>
>

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Wed, Feb 1, 2023 at 10:13 AM emanuel stiebler  wrote:

> On 2023-02-01 10:56, Warner Losh wrote:
> >
> > On Wed, Feb 1, 2023 at 1:41 AM emanuel stiebler via cctalk
> > mailto:cctalk@classiccmp.org>> wrote:
>
> > retension in case of power off.
> > If the power is applied all the time, the internal controller "can"
> > check the quality of the cells automatically (but this really
> > depends on
> > the controller, controller version, and the OS has to chose the right
> > strategy. And the controllers improved a lot lately)
> >
> >
> > The OS might not have a choice. All the SSDs that I've used in the
> > past decade at $WORK have not exposed any of this to the host, not
> > even enough stats to know when it's going on in real time... let alone
> > the ability to pause these operations for a little while until we're off
> > peak for the day...
>
> But you should be able to choose (at least on controllers I know) if you
> like to go for automatic or manual refresh.
>

That's selectable at the controller level... But there's no standard way for
the OS to turn that from one to the other... Unless you go all in and do all
the management which some NVMe drives support (not the ones we buy,
mind you, since this is an 'enterprise' feature and we buy in the 'consumer'
space).


> If you go for the automatic, it could happen that the drive decides to
> scan the drive, when your're busy and going nuts waiting for the drive
> (you can also define on newer drives how many block to check per run)
>
> If you're going for the manual refresh, just make sure you really run it
> one day. But, you should be the one who knows, when your computer isn't
> busy ...
>

We'd like to be able to do that, but the drives we buy don't expose those
knobs, despite buying many different models over the years from the same
vendors and developing a close relationship with them in which we ask for
it every chance we get...

Warner

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Wed, Feb 1, 2023 at 10:02 AM Ali via cctalk 
wrote:

> > However, it may well be that writing is the only way to refresh cells,
> > as reading won't, if I understand flash operation correctly.  But
> > rewriting a sector or block of a file doesn't usually write back to the
> > original, because of the write-leveling firmware in the drive.
>
> Chuck,
>
> But does that matter? If the main purpose is to be able to refresh the
> data so it is readable does it matter that the data is not in the same
> block as long as it is readable?
>

What's more, you don't always WANT to refresh the cells. Erase blocks
can only be erased and programmed a limited number of times. By writing
them every time, you are wearing out the NAND and making it less reliable
and able to hold the data with time. The first few program / erase cycles of
new NAND have the best retention for the unit. Once you get into the dozens
somewhere, the retention of the cells drops somewhat. Normally, this isn't
an issue, because dropping from decades to years for retention isn't a huge
deal for most applications. But when you want the data to last a long time,
you are better off just reading it and having those few (if any) cells that
have
decayed into the 'danger zone' refreshed, leading to likely 100x (or
better) less
wear on the part. The 'danger zone' is the error rate at which the firmware
will
decide the data is at risk in the future so it will rewrite the active
parts of the
erase block to ensure they are all readable in the future.

So by forcing a re-write every time, and doing that force rewrite often,
you are
actually making the device less capable of storing data for the long term.

Warner

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Wed, Feb 1, 2023 at 1:41 AM emanuel stiebler via cctalk <
cctalk@classiccmp.org> wrote:

> On 2023-02-01 00:00, Chuck Guzis via cctalk wrote:
> > On 1/31/23 20:16, Ali via cctalk wrote:
>
> > If you look at the specs for SSDs or any flash medium for that matter,
> > they're rated in terms of *write* cycles, which is why you don't want to
> > abuse that.
> right
> But, in most OS you can check the SMART data, to get an idea
>
> > However, it may well be that writing is the only way to refresh cells,
> > as reading won't, if I understand flash operation correctly.
>
> Reading ensures, that the cells are checked. if they fall below specific
> thresholds, they will be copied to another block
>

Indeed. It triggers the usual reliability engine in the drive. All data in
NAND is
stored with a number of redundant bits so that up to N errors can happen
and the data can be recovered. All NAND has a read error signal that
triggers well below N so that the data is all read and reconstructed (this
is normal on all reads), so it can then be written directly to the new
space.
Also, this isn't usually done on a PAGE pasis inside the NAND, but on an
entire erase block basis, because it's a leading indicator of problems to
come. Writing this data to a freshly erased block will mena it can be
read for some time into the future.


> > But
> > rewriting a sector or block of a file doesn't usually write back to the
> > original, because of the write-leveling firmware in the drive.
>
> right
>

Right.


> > JEDEC requires data retention of a consumer drive for at least 1 year,
> > which doesn't sound like much; real retention is probably much longer.
>
> retension in case of power off.
> If the power is applied all the time, the internal controller "can"
> check the quality of the cells automatically (but this really depends on
> the controller, controller version, and the OS has to chose the right
> strategy. And the controllers improved a lot lately)
>

The OS might not have a choice. All the SSDs that I've used in the
past decade at $WORK have not exposed any of this to the host, not
even enough stats to know when it's going on in real time... let alone
the ability to pause these operations for a little while until we're off
peak for the day...

And JEDEC retention is also at 20C, when the NAND is maximally
worn, with certain data access / write patterns leading up to that
wear. Most other wear patterns, especially archival ones, can
lead one to expect a much longer retention in all but the tiniest
processes storing 3 or 4 bits per cell.


> > You can write a script that write-refreshes every file on the drive.
>
> Please don't :)
> Just tell the controller to run a refresh ...
>

It would be even worse: since it could also trigger additional writes
as the new LBAs are written because the old erase blocks they
are in are now almost empty and new erase blocks will be needed
to write the new LBAs that are flooding the drive. The writes, and the
amplification writes will cause way more wear and tear on the drive
than doing a read scan of the whole drive (assuming you are impatient
about leaving the drive powered for the internal refresh...)


> > The easiest thing is to buy a second drive and ping-pong the data
> > between them periodically.   That way, if one fails, you still have the
> > other for backup.
>
> Disagree here, just run a compare between the two drives.
> a.) it will read all files, and the controller checks them in the
> background (will move them, if necessary)
> b.) you know, that after the compare you still have the data twice, on
> independent drives
>

c) You have less wear on both drives.

While a read could trigger a move due to read disturb, but that's only after
tens of thousands (or more) reads.

Warner

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Tue, Jan 31, 2023, 6:44 PM Paul Koning  wrote:

>
>
> > On Jan 31, 2023, at 8:38 PM, Warner Losh via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > On Tue, Jan 31, 2023, 5:03 PM Ali via cctalk 
> wrote:
> >
> >>> I thought Flash could only hold the data in them X amount of years
> >>> until
> >>> the junctions discharge or whatever? It's less permanent than decent
> >>> quality optical or pro magnetic media?
> >>>
> >>> You have to plug them in every so often to refresh I believe.
> >>
> >> Does REFRESHING mean reread and rewrite or just keep power to it? If
> it's
> >> the latter it should be trivial to setup a system with backup battery
> just
> >> to supply voltage to a bunch of SSD drives.
> >>
> >
> > It depends on the drive's firmware. Some do background scans of blocks
> > while idle. Others do not. Since you have no way of knowing which is
> which
> > (or even when the backgroundscan is done), the safest way to force a scan
> > is to read the whole drive... any blocks whose raw error count is too
> high
> > will be rewritten to fresh blocks. If it's a good SSD you'll likely not
> > notice this happening.  If it's a crappy thumb drive... you may be better
> > off copying to some other media..
> >
> > Warner
>
> Do you know what the likely answer is for "memory sticks", SD or MicroSD
> cards, things like that?  I assume their firmware is tiny, so are they
> likely to need active refreshing?
>

They are on the "copy it every so often" end of things. Especially if they
were slow when released.

Warner

>

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Tue, Jan 31, 2023, 5:03 PM Ali via cctalk  wrote:

> > I thought Flash could only hold the data in them X amount of years
> > until
> > the junctions discharge or whatever? It's less permanent than decent
> > quality optical or pro magnetic media?
> >
> > You have to plug them in every so often to refresh I believe.
>
> Does REFRESHING mean reread and rewrite or just keep power to it? If it's
> the latter it should be trivial to setup a system with backup battery just
> to supply voltage to a bunch of SSD drives.
>

It depends on the drive's firmware. Some do background scans of blocks
while idle. Others do not. Since you have no way of knowing which is which
(or even when the backgroundscan is done), the safest way to force a scan
is to read the whole drive... any blocks whose raw error count is too high
will be rewritten to fresh blocks. If it's a good SSD you'll likely not
notice this happening.  If it's a crappy thumb drive... you may be better
off copying to some other media..

Warner

-Ali
>
>

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Tue, Jan 31, 2023, 11:37 AM Ethan O'Toole via cctalk <
cctalk@classiccmp.org> wrote:

> > What do you guys think of the "archive-ness" of current solid state
> > devices?  M.2, NVMe, SSD, or even USB thumb sticks?   A friend proposed
> > that when one of those starts to go bad, any kind of partial data
> recovery
> > becomes difficult - but any more difficult than the old traditional
> > magnetic media?
>
> I thought Flash could only hold the data in them X amount of years until
> the junctions discharge or whatever? It's less permanent than decent
> quality optical or pro magnetic media?
>

Spec is 1 or 3 years retention at end of life. At start of life it can be a
decade for QLC parts or 30 years for SLC parts though those latter
numbers aren't guaranteed.

You have to plug them in every so often to refresh I believe.
>

Yes. And access all the used block for some firmware (some won't do
proactive scans).

Warner



>
> - Ethan
>
> --
> : Ethan O'Toole
>
>
>

[cctalk] Re: HP3000 recently deinstalled available in Colorado for nothing.

[Warner Losh via cctalk]

On Thu, Jan 26, 2023, 4:15 PM Angel M Alganza via cctalk <
cctalk@classiccmp.org> wrote:

> On 2023-01-26 19:01, ben via cctalk wrote:
>
> > If one really wanted it they would find a way.
>
> When you are 3000 Km away, maybe, but when you are at the wrong side of
> the pond it isn't that easy...  :-D
>

I'm less than 15km away.. But I really have the room to store it...

Warner

>

[cctalk] Re: in need of 2.5" disks

[Warner Losh via cctalk]

On Sat, Jan 21, 2023, 6:17 PM Chris via cctalk 
wrote:

> You read it right. I think only Zenith and Fujifilm made them.
>

Years ago I bought a portable with 2.5" floppies. It came with 1 disk that
was dodgy... I couldn't find disks then... and that was the 90s... good
luck.

Warner

>

[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man

[Warner Losh via cctalk]

On Fri, Jan 20, 2023 at 4:31 PM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

> On 1/20/23 16:05, emanuel stiebler via cctalk wrote:
> > On 2023-01-20 15:58, Bill Gunshannon via cctalk wrote:
> >> On 1/20/23 15:45, Ali via cctalk wrote:
>  The funny thing is that James and I were talking about doing some PCBs
>  and kits for the things, then decided that it would appeal to too few
>  people.  I still have the prototype, done in wire-wrap.
> >>>
> >>> Chuck,
> >>>
> >>> It may be a good time to dust off the old design and bring it out! ;)
> >>>
> >>
> >> Why?  There are already a number of functional (and in
> >> most cases cheap) floppy emulators.  It is unlikely
> >> even the boards could be made to match the price and
> >> in any case just how many of us do you really think are
> >> left?  :-)
> >
> > I was looking at Chuck's pertec interface this morning, and I really
> > like what he did. If he can pull of the same with the stm32f407 for
> > floppies, I'm in. Boards with the stm32 are cheap, and actually
> > available. And all in source, free compilers etc.
> >
> > (and MFM disks, ESDI disks, and, and ;-) )
>
> I would like something for MFM disks but that tends to be much more
> expensive than a $20 GOTEK.  I have a couple of Dave Gesswein's boards
> but haven't got around to building them yet.  I doubt it could be done
> cheaper and I don't think The Blue Pill has the horsepower to do it.
> Dave uses the Beagle Bone.
>

I bought mine assembled and tested. And I've had no problems with them at
all, modulo needing to work with David on a really weird disk I found in
the wild to get his software updated to cope that the weird pathology it
presented...  His devices are the best and well worth the money.

Warner

[cctalk] Re: Gotek as RX50 replacement for DECmate II

[Warner Losh via cctalk]

On Wed, Jan 11, 2023 at 8:14 PM h...@dec.dog via cctalk <
cctalk@classiccmp.org> wrote:

> appreciate the reply, Matt! unfortunately it doesn’t seem that that did
> the trick, another round of feeding it disk images and it still doesn’t
> want to boot.
>
> i tried the block and sector RX50 images on the dbit[.]com archive both
> as-is and converted to IBM MFM raw and HxC formats, and the teledisk images
> on ibiblio[.]org converted to the same.
>
> my img.cfg:
>
> [rx50]
> cyls = 80
> heads = 1
> secs = 10
> interleave = 2
> bps = 512
> id = 1
> rpm = 300
> rate = 250
> mode = mfm
> iam = no
>
> should i start suspecting my gotek (or worse, the system board) or is it
> still possible that i’m at fault?
>

I don't think you want the interleave. At least for the Rainbow and the Pro
they did do an interleave of 2, but it was done at the logical level, not
the physical level (which is confusing). So, if the images are physical
images (that is, they record the physical sector numbers that are on the
media), then you don't need it. If the images are logical (so some or all
of the tracks have the interleave applied), then you will need it.

Also, I think should be 0. Unlike the PC, where 1 and 0 are flipped by a
cable (you have a straight through cable, right?), the top RX-50 is ID 0
and the bottom is ID 1.

Warner


> —
> .hush
> Got interesting stuff to sell? Let me know!
> Looking for DEC, IBM, CDC, SGI, Data General, and more!
>
> > On Wednesday, Jan 11, 2023 at 8:47 PM, Matt Burke via cctalk <
> cctalk@classiccmp.org (mailto:cctalk@classiccmp.org)> wrote:
> > On 12/01/2023 00:58, h...@dec.dog via cctalk wrote:
> > > hello cctalk! i have been working for the past few days on a DECmate
> II with what i believe to be an ailing RX50. i have a gotek with updated
> flashfloppy firmware, but for some strange reason i have been completely
> unable to get the DMII to boot a floppy image from it.
> > >
> > > i have been trying to convert the OS/278 and WPS images on the dbit
> and ibiblio archives into a working format for the gotek but none of them
> will work. at this point i have tried too many conversions to recall but
> they all result in the same blinking floppy icon when the unit boots. i
> have “host = dec” in my FF.CFG per the wiki.
> > >
> > > has anyone else been able to get this working? if so, could you please
> provide known-good images for a gotek, or the steps to generate them?
> > >
> >
> > I've used a Gotek (semi-successfully) with the DEC Rainbow using raw
> > image files and the following lines in ff.cfg:
> >
> > host = dec
> > pin02 = low
> > pin34 = rdy
> >
> > The image file format should not be important though you may run into
> > problems with sector ordering depending on how the source image was
> > created. It was the pin02 and pin34 lines that got it working for the
> > Rainbow.
> >
> > Matt
>

[cctalk] Re: Reading Old Floppies

[Warner Losh via cctalk]

On Mon, Jan 9, 2023 at 12:19 PM Glen Slick via cctalk 
wrote:

> On Mon, Jan 9, 2023, 10:23 AM Warner Losh via cctalk <
> cctalk@classiccmp.org>
> wrote:
>
> > On Sun, Jan 8, 2023, 6:29 PM Zane Healy via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> >
> > Also, a normal USB Floppy drive can only handle 1.44MB formatted
> floppies.
> > 720k might work (but there is nothing in the standards to describe this)
> > and oddball formats are right out.
> >
> > Warner
> >
>
>
> https://www.usb.org/sites/default/files/usbmass-ufi10.pdf
>
> USB Mass Storage Class – UFI Command Specification Revision 1.0
> 4.10.2 Formattable Capacity Descriptors
> The UFI device supports the following capacity descriptors.
> Table 35 - Capacity Descriptors Supported by USB-FDU
> DD 720 KB
> HD 1.25 MB (1024-byte sectors)
> HD 1.44 MB
>

Indeed... I had a memory of it not doing even the 720k drives, but either I
found an old copy of the standard years ago when I was looking at this, or
I just misremembered no support for 5.25" floppies at all as only
supporting 1.44MB HD format...

Thanks for the correction...

Warner

[cctalk] Re: Reading Old Floppies

[Warner Losh via cctalk]

On Sun, Jan 8, 2023, 6:29 PM Zane Healy via cctalk 
wrote:

> When reading old floppies, how often is it advisable to clean the drive?
> I managed the first 3.5” floppies no problem, I’m using a USB Floppy Drive
> hooked up to my Mac Laptop, I was able to image them using “Disk Utility”.
> The next two floppies have had errors.  Though I think I was able to
> successfully copy all the files off the one.
>
> Also, what is floppy drive cleaning fluid made of, and how well does it
> age?  I know I’ve got at least a couple cleaning floppies around here, but
> they’re *OLD*.
>


Also, a normal USB Floppy drive can only handle 1.44MB formatted floppies.
720k might work (but there is nothing in the standards to describe this)
and oddball formats are right out.

Warner

>
>
>

[cctalk] Re: Reading Old Floppies

[Warner Losh via cctalk]

For 5.25" RX50 floppies, I imaged 400 of them before I needed to clean the
drive... and even then I'm not sure it needed it...

Warner

On Sun, Jan 8, 2023, 6:29 PM Zane Healy via cctalk 
wrote:

> When reading old floppies, how often is it advisable to clean the drive?
> I managed the first 3.5” floppies no problem, I’m using a USB Floppy Drive
> hooked up to my Mac Laptop, I was able to image them using “Disk Utility”.
> The next two floppies have had errors.  Though I think I was able to
> successfully copy all the files off the one.
>
> Also, what is floppy drive cleaning fluid made of, and how well does it
> age?  I know I’ve got at least a couple cleaning floppies around here, but
> they’re *OLD*.
>
> Zane
>
>
>
>

[cctalk] Re: Downsizing "feeler"

[Warner Losh via cctalk]

On Sat, Jan 7, 2023 at 1:59 PM Glen Slick via cctalk 
wrote:

> On Sat, Jan 7, 2023, 11:12 AM George Currie via cctalk <
> cctalk@classiccmp.org> wrote:
>
> I need to go through and hit some highlights, but there are things from
> rack mount PDP-10's
>
> --
>
> Did you really mean PDP-10 instead of PDP-11?
>

That caught my eye too... There aren't too many of them working or nearly
working around...

Warner

[cctalk] Re: loading vt220 fonts

[Warner Losh via cctalk]

On Sat, Jan 7, 2023, 1:04 AM Lars Brinkhoff via cctalk <
cctalk@classiccmp.org> wrote:

> Grant Taylor wrote:
> > I'm not that surprised that soft fonts are (re)using Sixel.
>
> Maybe the other way around.  I don't really know what the timeline was,
> but it seems to me maybe soft fonts came first, with the VT220.  The
> VT240 had sixel graphics, right?  But I'm guessing it came later.  As
> would the VT340.
>

Vt240 had graphics. But the LA50 also had sixel graphics, as did the vt125.
Regis graphics was built on sixels :)

Warner

> I suspect that means that XTerm could support soft fonts if some minor
> > changes were made to re-use it's existing Sixel support.
>
> Probably.  I had the good fortune to meet the person who first added
> sixel graphics to XTerm, and he mentioned it is on his to-do list.
>
> It would also be interesting to make a faithful VT220 emulator that runs
> the original ROMs.
>
> >> But apparently you saw that already!
> > Nope.  But I have now.  :-)
>
> Oh, isn't this you?
> https://twitter.com/DrScriptt/status/1187958760901414913
>

[cctalk] Re: best C compiler(s) for varied vintage programming

[Warner Losh via cctalk]

On Tue, Dec 27, 2022, 7:31 AM Chris via cctalk 
wrote:

>  Apparently Northstar's dos is yet another amended version of ms-dos. I
> suppose it was supplied for basic tasks, as it couldn't possibly provide
> all the features supplied by Netware. So whereas this may not be as
> difficult as I thought, there are still significant hurdles. The floppy
> drive's transfer rate is 250kbits/s. That probably isn't significant.


The Dimension machine you have is PC compatible, more or less, according to
the various places I found last night.

In that era, MS-DOS provided part of the solution. It did the program
loading and filesystem services. The ROMs provided the rest. The difference
between the different MS-DOS versions for things like the Rainbow, Victor,
Tandy etc were all in the IO.SYS file that handled the device drivers for
the machines in question. It also handled the different floppy formats and
often times hid the second stage boot loader in funky, machine specific
places.

In that era too a lot of software was in the ROMs and that's where 90-95%
of the non-timing incompatibility was: The ROM routines weren't complete in
the early clones (of which the Dimension was). And that was before there
was one video card standard, so going direct to video memory  was tricky
(possible, and a lot of people did it, but there were many articles about
how to probe for what's there, how to structure your code to make it less
hard but still fast, etc).

I suspect there is more there than you think, but probing it, or recreating
the boot disks may require some unique to the machine fiddling...

Warner

>

[cctalk] Re: best C compiler(s) for varied vintage programming

[Warner Losh via cctalk]

OK. You guys are all over the place.

I do think you are confusing Compiler and Run Time first off.

I ran Turbo C on my DEC Rainbow which had MS-DOS compatibility but not
PC-DOS/PC BIOS compatibility.
TCC would run in this environment (modulo it's use of INT 18 which I did a
hack to allow on the Rainbow
which used that interrupt for its screen code).

TCC would read files off the disk with MS-DOS calls to open the file, etc.
Same with writing. It worked
on all machines because it did this. It was no different than MASM or other
command line compilers at
the time which generally (but not always) avoided PC BIOS calls.

For the Rainbow, if I wanted to use vanilla DOS, I used the default run
time. If I wanted to use an optimized
version that I had back then (but haven't seen recently), I had to add a
bunch of command line flags to get
it to swap out what's the equivalent of libc.a and crt0.o on Unix/Linux.

So, you could write a program than runs on any MS-DOS computer. Or, you
could use your own libc to do
the low-level stuff and have it run on a specific computer. It would still
need to be MS-DOS (though CP/M 86
was possible with a .EXE to .CMD converter and there were also hacks to
convert the .OBJ files to .o
files that some Unix-based loaders could cope with, but I really haven't
seen those anywhere in a long time,
though I've not needed to look). DOS handled all the weird formatting
differences between a
DEC Rainbow, IBM-PC and whatever other weird thing TCC ran in (at least in
the early days). There was also
no official support for the DEC Rainbow after the first TCC release (which
is why I had to do the INT 18
hacks).

If you wanted to run on raw hardware, though, you'd need to write a boot
loader, which is way beyond the
scope of this email :).

Of course, you can use dosbox or similar to run the old-school compilers /
assemblers to generate the binaries
on Linux / FreeBSD. I've done this lately...

So if it is running MS-DOS, there's a chance you can run TCC at least on it
(at least early versions). The early
versions were more MS-DOS-centric and less 'only runs on PC-DOS' at least.
I moved on to FreeBSD/Linux
around this time, so I don't know how things evolved.

Warner

On Mon, Dec 26, 2022 at 10:40 PM Chris via cctalk 
wrote:

>  Ok now some things are coming back. Borland compilers work from the
> ms-dos command line. Bcc 5.5? came with an old textbook. But the Dimension,
> although I assume has some sort of command line structure, doesn't have an
> ms-dos command line. So let's just say tje program got up and running, even
> compiled code (all that assumes a lot). How is it going to save the .obj
> file. The file structure of Northstar dos would have to be identical to
> ms-dos, 8.3. It would have to be able to read an ms-dos formatted disk. And
> the main kicker is the object codw format, creating a 256 byte psp. Amongst
> other shit I have to assume. Or does ms-dos itself handle some of that. Is
> a compiler'a executable format compatible with this. This thing is binary
> compatible in a broad sense. But can you simply for instance run Linux
> wares on bsd?

[cctalk] Re: what is on topic?

[Warner Losh via cctalk]

So long as we don't talk about what is or isn't allowed, the list traffic
is low enough not to need specific rules...

Except maybe not talking about what is vintage. :p

Warner

Ps :p is retro emoji :).

On Tue, Dec 20, 2022, 9:58 PM Chris via cctalk 
wrote:

>  Nah. The nays would habe to outnumber the yays. You can always find 3
> malcontents who hate everything. But that sucks as well because you get
> involved with runoffs. And subsequently voter fraud,
> hangimg/dimpled/pregnant chads, storming of the capitol server. Holey moley
> let's end this topic now.
>
> Voting doesn't work anyway when you live imside a caliphate. We have yet
> to hear from the Big Kahuna.
>  On Tuesday, December 20, 2022, 11:46:06 PM EST, Sellam Abraham via
> cctalk  wrote:
>
>  This is really funny.  Do you all realize how many times we've gone over
> this over the past 25 years?
>
> As Bill poignantly explained, maybe instead of trying to establish a
> cut-off date, we instead think outside of the box:
>
> If enough people object to a topic, it stops.  Let's call it three
> objections.  If three different people reply to a post objecting to it then
> whoosh, off it goes into the bit bucket, never to be spoken of again.
>
> Example:
>
> Someone A: Hey, is it OK if I talk about Windows 11?
> Someone B: Objection.
> Someone C: Objection.
> Someone D: Objection.
> Someone A: Ok, sorry [bashfully skulks away]
>
> Food for thought.
>
> Sellam
>
>
> On Tue, Dec 20, 2022 at 8:33 PM Tony Jones via cctalk <
> cctalk@classiccmp.org>
> wrote:
>
> > Traffic on the list is so low I'm not seeing the issue.I'm also not
> > seeing complaints about threads being off topic.Seems like solution
> > seeking a problem.
> >
> > On Tue, Dec 20, 2022, 8:28 PM Chris via cctalk 
> > wrote:
> >
> > >  On Tuesday, December 20, 2022, 11:11:27 PM EST, Fred Cisin via cctalk
> <
> > > cctalk@classiccmp.org> wrote:
> > >
> > >
> > > I was not disagreeing with you.
> > >
> > >
> > > Ok. Wonderful. I guess we've sufficiently established that from
> > henceforth
> > > anything dang-old is totally on topic. Any detractors? :)
> > >
> > > Transcoding as in vcr to mpegs? I wasn't suggesting XP was utterly
> > > entirely useless. Video editing in a modern sense requires loads of
> > > processing h.p. to be efficient. And no transcodimg is necessary.
> > Certainly
> > > not an expert. But I should think older hardware would be very very
> slow.
> >
>

[cctalk] Re: Old Silicon Valley poster

[Warner Losh via cctalk]

On Sat, Dec 10, 2022, 5:59 PM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

> On 12/10/22 18:27, John Foust via cctalk wrote:
> >
> > Well, she went for $810 to a map dealer in London, and he had to pay
> > about another $200 for the eBay global shipping program and duties.
> >
> > I asked one of the other losing bidders about what I had here and why it
> > was popular...  he said "Dealers are collecting them and
> > trying to sell them at various price points. So far sales
> > have been pretty minimal at anything over $1000. The
> > exception is that some libraries are starting to collect
> > them with an eye on the future."
> >
> > I'll see if I can stitch a good scan before I ship it out.
> >
>
> I wonder what my Unix Wizard poster is worth? (not that I would ever
> part with it!!)
>

Last I priced mine, they were going for 100-200 USD. But there aren't many
for sale ...

Warner

>

[cctalk] Re: Inline Serial Device?

[Warner Losh via cctalk]

On Sat, Nov 12, 2022, 4:41 PM Glen Slick via cctalk 
wrote:

> On Sat, Nov 12, 2022 at 12:36 PM Chuck Guzis via cctalk
>  wrote:
> >
> > On 11/12/22 11:56, ben via cctalk wrote:
> > > On 2022-11-12 12:33 p.m., Chuck Guzis via cctalk wrote:
> >
> > > Watch out for Indians. :)
> > > Ben.
> >
> > Nonsense--they have some very fine restaurants here.
> >
> > --Chuck
>
> I went to an Endian restaurant once. I was disappointed. I wanted
> something little, but everything on the menu was big.
>

I'm never quite sure which way to read the menu there, but the food is good.

Warner

>

[cctalk] Re: Exabyte recovery

[Warner Losh via cctalk]

On Wed, Nov 9, 2022 at 7:52 PM Warner Losh  wrote:

> I have a few old exabyte tapes of possible historic value. Who can I pay
> to get them recovered that has the best chance of success?
>

These are 4GB tapes, I believe. Made in 1992 or 1994 give or take. They are
in Sun dump format. i need the bits at least, but decoding from dump format
wouldn't be bad. they are level 0 backups.

And I'm really hoping to find a good service to do due to the age... I'd
rather not do it on my own, even though it's easy enough to connect the
equipment...

Warner

[cctalk] Exabyte recovery

[Warner Losh via cctalk]

I have a few old exabyte tapes of possible historic value. Who can I pay to
get them recovered that has the best chance of success?

Warner

[cctalk] Re: Finding tar block size.

[Warner Losh via cctalk]

On Tue, Oct 11, 2022 at 4:14 PM Chris Zach via cctalk 
wrote:

> Trying to tar a directory and transfer it to my AT 7300 (SVR2 unix).
> Tar -tf works fine on the Mac OSX, but when I copy it over the Unix (not
> gnu) tar gives me a:
>
> Tar: blocksize = 20
> directory checksum error
>
> When I try to tar -tf the file. Which usually means the block size is off.
>
> Any way I can check to see what the block size is on a modern system
> (like a Mac)? tar -tvf doesn't seem to tell me.
>

All tar files are the same... except when they are different.

MacOS uses libarchive tar. This version of tar creates the most modern tar
files from the
mid 90s.

However, System V r2 pre-dates that. There's a lot of different tar
formats, that are almost
the same. I'm guessing that --format pax might work, but it might not.
--format ustar like is
the most interchangeable format, and will likely work. It's the
least-restrictive format that
will most likely work. --format v7 will almost certainly work, but has more
restrictions that
might run into, most likely its inability to use anything except numeric
IDs.

Warner

[cctalk] Re: Minicomputer front panel.

[Warner Losh via cctalk]

On Fri, Sep 23, 2022 at 2:22 PM Fred Cisin via cctalk 
wrote:

> On Fri, 23 Sep 2022, Paul Koning via cctalk wrote:
> > There might be some exceptions: a spare RF11 or RC11/RS64 platter merely
> > needs to be bolted to the spindle hub and formatted, that's a normal
> > field repair procedure.  But, say, a platter out of an RP04 pack is
> > unlikely ever to be able to serve as anything more than a wall hanging
> > or a prop.
>
> I made a patio table out of a damaged 24" diameter RAMAC platter.
>

Nice...

My old boss made the platter from the crashed RP-03 that we had at work
into a clock...

Mine is still hanging up in my computer room as a memento from the past...

Warner

[cctalk] Re: VCF Swap Meet October 8, 2022 @ InfoAge

[Warner Losh via cctalk]

On Sun, Sep 11, 2022, 1:51 PM Will Cooke via cctalk 
wrote:

>
>
> > On 09/11/2022 12:47 PM CDT Jeffrey Brace via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> >
> > The following info is found here: https://vcfed.org/vcf-swap-meet/, but
> I'm
> > pasting here for your reference.
> >
>
> Interesting.  Unless I'm blind, nowhere in that email or the linked flyer
> does it state what city and state (or country) it's in.
>

There is a map to someplace in New Jersey

>

[cctalk] Re: MicroVAX CTI (DEC Professional) card

[Warner Losh via cctalk]

On Fri, Sep 9, 2022, 3:24 PM Lee Gleason via cctalk 
wrote:

>
>Took some pictures of the MicroVAX CTI card, and another odd card I
> got - an 8086 CTI smartcard. See 'em both at
>
>
> https://rsx11.blogspot.com/2022/09/microvax-and-8086-smartcards-for-dec.html


The 8086 card was likely for DOS or CP/M-86 programs... It likely predates
windows and didn't seem to have graphics parts / output (though I suppose
the latter could be over the bus...)

Warner


> --
> Lee K. Gleason N5ZMR
> Control-G Consultants
> lee.glea...@comcast.net
>
>
>

[cctalk] Re: Wang bar napkin story [WAS:RE: Re: "Revival" of a dedicated Micropolis webpage on internet]

[Warner Losh via cctalk]

On Mon, Aug 22, 2022 at 7:13 AM Paul Koning via cctalk <
cctalk@classiccmp.org> wrote:

>
>
> > On Aug 21, 2022, at 8:35 PM, W2HX via cctalk 
> wrote:
> >
> > I always thought it was interesting how 5 1/4 is 3U (rack units). I
> thought there might have been some relationship to that. But could have
> been just coincidence.
>
> For floppies, likely yes.  That fact did get used later on, in storage
> arrays where you can line up 14 or so disk drives, standing on edge, in a
> 3U 19 inch rack mounted system.
>

I thought the initial 5.25" Hard Disks had ISSUES[tm] operating on edge. I
remember the RD50 (5MB in all its glory) being touted as also operating on
edge for the desk-side cases for DEC Rainbows and Professionals (and later
MircoPDP-11s).

Warner

[cctalk] Re: "Revival" of a dedicated Micropolis webpage on internet

[Warner Losh via cctalk]

On Tue, Aug 16, 2022 at 11:33 AM Jonathan Chapman via cctalk <
cctalk@classiccmp.org> wrote:

> > I think it was Dysan that first showed up with reinforcing ring kits
>
> Probably, "Grabettes."
>
> > Then why was is it that DD media bought well after HD media was
> available, in use, and the norm still had the reinforced ring? Tradition?
>
> You might be putting it in an old drive. It was also available without, I
> had several thousand without reinforcements from Verbatim, bought in bulk
> bags.
>

It was a matter of much debate whether or not you wanted hub rings on an
RX-50 (though I believe my recollection from back in the day landed on the
not side).

Warner

[cctalk] Re: VT220 North of Boston

[Warner Losh via cctalk]

On Tue, Aug 9, 2022 at 11:30 AM Fred Cisin via cctalk 
wrote:

> >> Boston GB, Boston USA or Boston somewhere else?
>
> On Tue, 9 Aug 2022, Dave Wade G4UGM via cctalk wrote:
> > There are apparently 16 Bostons in the USA
> > https://geotargit.com/citiespercountry.php?qcountry_code=US=Boston
>
> Perhaps you could differentiate by how far it is from Springfield.
>

Or how far it is from a well known landmark, like the Simpson's Home?

Warner

[cctalk] Re: Connecting a physical terminal via LAN to Serial Port

[Warner Losh via cctalk]

On Sun, Jul 31, 2022, 1:29 PM Paul Koning via cctalk 
wrote:

> Either way, a complete system might cost 10-20 dollars.  Check our
> "Arduino Nano" or "Adafruit Trinket".  I used the latter in my LK201
> keyboard emulators.
>

Are these available? If, what's the details?

Warner

[cctalk] Re: Dec pdp 11 ultrix

[Warner Losh via cctalk]

On Sat, Jul 30, 2022 at 1:20 PM Ron Pool via cctalk 
wrote:

> > 7m was the Bell Labs unix that came after v6. I've got the disks
> > somewhere around here, are there other copies out there?
>
> There is a copy of the contents of a 7m distribution tape at:
> https://www.tuhs.org/Archive/Distributions/DEC/Jean_Huens_v7m/
>
> Along with the tape contents, there are also notes on bringing it
> Up under SIMH.
>

http://bitsavers.org/pdf/dec/pdp11/ultrix-11/Unix_V7M_Release_2.1_Software_Description_Sep81.pdf

is also helpful. It explains what hardware is supported, and includes how
to set
things up. When I played with it, I used this doc rather than the TUHS doc
because
I somehow overlooked the TUHS docs on how to set it up... In all honesty,
the TUHS
docs, had I read them, would have saved me a bit of time...

Warner

[cctalk] Re: What is an "FS/2" connector?

[Warner Losh via cctalk]

On Sat, Jul 30, 2022, 5:21 PM Chuck Guzis via cctalk 
wrote:

> On 7/30/22 15:16, Fred Cisin via cctalk wrote:
>
> >
> > But, I'm REALLY hoping that someday you will elaborate in length about
> > the MS-DOS 2.11 and 3.31 OEM configuration capabilities and limitations!
>
>
> My recollection (very hazy after about 40 years) from DOS 2.x is that as
> an OEM you supplied the IO.SYS and low-level utilities.   If you look at
> the MSDOS 2 or 6 source code (available on the web), there are scads of
> adjustments in the code for the large OEMs like Compaq.
>

That's certainly what DEC did with its Rainbow...

Warner

>

[cctalk] Re: Agenda VR3 MIPS cross-gcc

[Warner Losh via cctalk]

On Sun, Jul 24, 2022, 11:09 PM Cameron Kaiser via cctalk <
cctalk@classiccmp.org> wrote:

> There used to be a cross-compiling gcc for MIPS specifically for the
> VR4121 in
> the Agenda VR3 PDA, but it doesn't seem to be on any of the remaining
> sites.
> Anyone out there got it or, he asked hopefully, the entire SDK? Binaries
> OK,
> source better.
>

NetBSD/hpcmips supports the Vr42xx chips...

Warner

-- 
>  personal:
> http://www.cameronkaiser.com/ --
>   Cameron Kaiser * Floodgap Systems * www.floodgap.com *
> ckai...@floodgap.com
> -- You can't fool me: there ain't no Sanity Clause. -- Chico Marx
> -
>
>

[cctalk] Re: Dec pdp 11 ultrix

[Warner Losh via cctalk]

On Fri, Jul 29, 2022, 8:58 PM devin davison via cctalk <
cctalk@classiccmp.org> wrote:

> Thank you for the suggestion, but what is 7m? i have done a few seacches
> but not turned up much.
>

DEC fixed a few bugs in V7 and expanded hardware support and called it 7m.

Sounds promising, if i can find install media ill give it a try in simh.
>

https://www.tuhs.org/Archive/Distributions/DEC/Jean_Huens_v7m/

Warner

Thanks,
>
> Devin D.
>
>
>
>
> On Fri, Jul 29, 2022, 10:53 AM Chris Zach via cctalk <
> cctalk@classiccmp.org>
> wrote:
>
> > I know you can run 7m as I have a couple of RL01 packs with 7m on them.
> > You needed two drives.
> >
> > RSX11/M 4.2 would probably be the best OS for a 34.
> >
> > On 7/26/2022 11:52 PM, devin davison via cctalk wrote:
> > > Hello,
> > >
> > > Been a while since i last posted here.
> > >
> > > I have a few pdp 11/34 systems. The drives i am using are RL02 drives.
> > >
> > > Is it possible to install Ultrix on a 34? I have been testing out
> Ultrix
> > in
> > > the simh emulator. I see during the install the 34 mentioned as a
> > > recognized cpu type, but later in the install the system hangs. This
> hang
> > > does not occur if i emulate a later cpu system like the 11/83.
> > >
> > > Not sure if ultrix can be installed due to the memory limitation, if
> not,
> > > rsx will be my second choice.
> > >
> > > Hoping to have some real hardware running soon!
> > >
> > > Thanks,
> > >
> > > Devin D.
> >
>

Re: Cross-tools

[Warner Losh via cctalk]

On Tue, Jun 28, 2022 at 6:08 PM Paul Koning  wrote:

>
>
> > On Jun 28, 2022, at 5:25 PM, Warner Losh  wrote:
> >
> >
> >
> > On Tue, Jun 28, 2022 at 3:03 PM Paul Koning via cctalk <
> cctalk@classiccmp.org> wrote:
> > I'm looking for cross tools for PDP11.  I know of macro11, and have been
> feeding Olaf assorted fixes.
> >
> > I built my own LIBR (in Python, that was easy enough).
> >
> > So now I'm looking for LINK and TKB.  I found this:
> https://github.com/nzeemin/pclink11 but it says no overlay support and
> may never happen.  Are there others, and is there any overlay support?
> >
> > What about a cross-TKB?
> >
> > My hope is to be able to cross-build all of RSTS that is in assembly
> language.
> >
> > When I did the 2.11BSD restoration project, I used the apout emulator to
> run assemblers, linkers, etc.
> >
> > Are there any user-mode emulators that support RSTS/E system calls?
>
> Not that I know of, and most of the RSTS utilities are in PDP-11 assembly
> language.  So I can run things on SIMH, of course, but cross-builds are
> much faster.  Running the RSTS kernel and loader through the cross macro11
> takes only about 8 seconds of CPU time.
>

Yea, apout ran things in << 1s, so it flies by and is no where near the
long pole in the scripts I wrote to reconstruct patches...

There is a macro assembler and linker that run on V7 and later, but I don't
think that will help you all that much (though it appears to have some
vestiges of OBJ support, I've never tried to enable it).

Warner

Warner

Re: Cross-tools

[Warner Losh via cctalk]

On Tue, Jun 28, 2022 at 3:03 PM Paul Koning via cctalk <
cctalk@classiccmp.org> wrote:

> I'm looking for cross tools for PDP11.  I know of macro11, and have been
> feeding Olaf assorted fixes.
>
> I built my own LIBR (in Python, that was easy enough).
>
> So now I'm looking for LINK and TKB.  I found this:
> https://github.com/nzeemin/pclink11 but it says no overlay support and
> may never happen.  Are there others, and is there any overlay support?
>
> What about a cross-TKB?
>
> My hope is to be able to cross-build all of RSTS that is in assembly
> language.
>

When I did the 2.11BSD restoration project, I used the apout emulator to
run assemblers, linkers, etc.

Are there any user-mode emulators that support RSTS/E system calls?

Warner

Re: Viking SCSI controller RS232 adapter

[Warner Losh via cctalk]

On Tue, Jun 28, 2022, 1:21 PM Zane Healy via cctalk 
wrote:

> On Jun 28, 2022, at 12:10 PM, Daniel Seagraves via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > For the UDT at least the RS232 lines are regular RS232 and the plug I
> made for communicating with it was just an old PC serial pigtail bodged
> onto a short SCSI ribbon cable.
> >
> > I would expect CON to be CONfiguration port; No idea what FP is for.
>
> That’s good to know.  If you have the actual adapter, it will work for
> both the Unibus and QBus boards.  So what worked for use for a UDT, should
> work on a QBus board
>

You may need to hook a scope to TX lines to know the right levels...

Warner

>

Re: IBM PC Connecting to DECNET

[Warner Losh via cctalk]

Speaking of DEPCA, does anybody (a) know what kind of mouse connects (the
docs just say DIGITAL MOUSE) and (b) know where to get one?

Warner

On Thu, Jun 2, 2022 at 9:47 PM Bill Degnan via cctalk 
wrote:

> On Thu, Jun 2, 2022 at 10:09 PM Rick Murphy via cctalk
>  wrote:
> >
> > On 6/1/2022 12:49 AM, Glen Slick via cctalk wrote:
> > > No one ever called it a "Digital Ethernet Personal Computer Bus
> > > Adapter", just a DEPCA. I never previously knew that there was any
> > > meaning behind the DEPCA name.
> >
> > Yes, that's what it meant. "DELNI" - Digital Ethernet Local Network
> > Interface. "DESTA" - Digital Ethernet Station Termination Adapter. DELQA
> > - Digital  Ethernet Local Q-Bus Adapter (this one probably means
> > something else. Working?). DEMPR - Multi Port Repeater. DEREP -
> > Repeater.  And so forth. Yeah, nobody spelled it out, but those DExxx
> > names usually meant what the device was. DEBNT, DEUNA, DEQNA. Same
> > naming convention. I'm probably missing several.
> >  -Rick
> >
>
> I ended up getting it all working.   I found the DEPCA card I needed,
> the correct scripts now run, etc.  I tore down my VAX cluster some
> time ago, I would need to set up a new one, change the scripts to
> match the services available and the names to continue with this
> project.
>
> BIll
>

Re: IBM PC Connecting to DECNET

[Warner Losh via cctalk]

On Wed, Jun 1, 2022 at 7:51 AM Paul Koning  wrote:

>
>
> > On Jun 1, 2022, at 5:53 AM, Warner Losh via cctech <
> cct...@classiccmp.org> wrote:
> >
> > ...
> > I believe the DEPCA was based on the venerable
> > SONIC chipset, but it may have been the LANCE. It wasn't NE-2000
> compatible
> > (that came later) :).
>
> LANCE seems plausible, or perhaps one of the later chips designed by DEC
> Jerusalem (SGEC etc.).  What's a SONIC?
>

SONIC was NatSemi part that a lot of workstations of the early 90s used. It
does post-date LANCE by a few years.


> The non-LANCE non-DEC Ethernets I remember are in the DEUNA (no idea
> what), QNA (Fujitsu???) and CNA (Intel 82586, *groan*).  The LANCE was
> designed well, with a fair amount of DEC input, and the subsequent
> internally produced chips were constructed along similar lines.  Once DEC
> learned  how to make them at not quite insane cost, they became a very good
> choice and were generally used in DEC products.
>

The LANCE and its children were nice chips.

There's several DEPCAs for 8-bit ISA on ebay for about $50 (and a couple
for a lot more), and as others have pointed out it is a variation of the
Am7990.

Warner

Re: IBM PC Connecting to DECNET

[Warner Losh via cctalk]

On Tue, May 31, 2022 at 10:08 PM Wayne S via cctech 
wrote:

> I think Decnet can run over a serial connection (rs-232) if you have
> Decnet software. It’s not medium dependent. I got it to work years ago from
> vax-to-vax. I’m not aware of any pc decnet software although I haven’t
> looked much into it. Should work over ethernet too. Do you have any Decnet
> pc software?
>

The first PC version of DECnet was over serial. There's copies of it in
bitsavers.org. The second version had ethernet support. There's copies of
the IBM PC version of that software on bitkeepers, but not the DEC Rainbow
version, alas. Then again, the Ethernet card for the DEC Rainbow is quite
rare these days (I've not seen one in 15 years of looking), as is the
software that describes how it was put together.

http://bitsavers.trailing-edge.com/bits/DEC/decnet/

is the archive. If you want ETHERNET, you should use the V2.0 or newer
code. V1.1 was serial only. I believe the DEPCA was based on the venerable
SONIC chipset, but it may have been the LANCE. It wasn't NE-2000 compatible
(that came later) :). The Rainbow design supposed was quite similar, but
I've only been able to find old review articles about it, nothing concrete.

Warner


> Sent from my iPhone
>
> > On May 31, 2022, at 20:57, Bill Degnan via cctech 
> wrote:
> >
> > Here is a link to a set of screen shot of the autoexec.bat and
> > config.sys for an IBM PC I came across today and the boot screen when
> > these are attempted without the networking hardware attached..
> >
> > https://www.vintagecomputer.net/IBM/5150/5150_DEC/
> >
> > Specific to IBMPC to DECNET networking...anyone worked in this
> > environment?  Not me.  I don't have the D drive that fails or the
> > network, but I am curious what I would need to make this work.  Maybe
> > I can put something together.  Anyone using a Digital Ethernet
> > Personal Computer Bus Adapter today?
> >
> > The A drive had a jumper between 4-pin connectors 10 and 13 but it was
> > not functional and I replaced the drive entirely.  Not sure if I
> > needed a 720K drive attached externally or something in order for the
> > 5 1/4" drive jumpered this way to work.  I have a pic of this there
> > too.
> >
> > Weird.
> >
> > Thanks in advance.
> >
> > BIll
>

Re: Slashed letter O, unslashed letter zero

[Warner Losh via cctalk]

On Tue, Apr 26, 2022 at 11:25 AM Shoppa, Tim via cctalk <
cctalk@classiccmp.org> wrote:

> This website has a history of slashing the letter O (and also ticked,
> center-dotted, etc.) oriented around computing:
> https://circuitousroot.com/artifice/letters/characters/slashed-o/index.html


Now I understand...

For me, who started coding in the late 70s, it was always the number 0 that
was slashed, dotted, or otherwise made to look 'odd', never the letter o.

Warner

Re: DEC RX50 mysterious 81st cylinder

[Warner Losh via cctalk]

On Sat, Apr 23, 2022, 10:11 PM Bjoren Davis via cctalk <
cctalk@classiccmp.org> wrote:

> Hello Retroovers,
>
> Here's something interesting that Oleksii in Ukraine discovered.
>
> While playing with a Fluxengine, he found that some RX50s have data,
> stored in FM format, in a single sector the 81st track of the diskette.
>
> For fun I went through my collection of original DEC distribution
> diskettes for the DEC Professional, read the single sector and compared
> them.
>
> Here is what I found:
>
> Common data (locations with variations marked with __):
> 00:   46 4d 54 20 4d 46 4d 20 4e 4f 2f 46 43 20 31 2a   |FMT MFM NO/FC 1*|
> 10:   31 30 2a 35 31 32 20 38 30 54 20 2d 44 45 43 20   |10*512 80T -DEC |
> 20:   52 58 35 30 00 20 20 20 32 32 32 36 34 2d 32 33   |RX50. 22264-23|
> 30:   20 20 __ __ 84 __ __ __ 20 46 01 f5 30 30 __ 30   | __.___ F..00_0|
> 40:   __ __ __ 20 20 20 20 20 20 20 20 20 20 20 20 20 |___ |
> 50:   20 20 20 20 82 f1 c8 54 9a fd ce 57 9b 7d 0e b7   | ...T...W.}..|
> 60:   6b 05 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |k.  |
> 70:   20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 ||
>
> Variations:
>   offset
> 32 3335 36 373e40 41 42
> file   ---
> BL-AI19C-BH04 0210 34 193031 35 30
> BL-CF74C-BH03 2600 01 363030 39 30
> BL-CF74C-BH03 2600 03 453030 39 30
> BL-CL73B-BH11 1000 53 443030 37 31
> BL-HC42A-BH04 0919 59 543031 33 30
> BL-HD04A-BH01 2117 26 093031 34 30
> BL-HD04B-BH01 0711 34 013030 f3 31
> BL-HD04B-BH06 1802 24 013030 31 30
> BL-HD05A-BH01 2202 33 403032 30 31
> BL-HD05B-BH02 1119 59 513030 30 31
> BL-HD05B-BH02 1120 00 553030 30 31
> BL-HD06A-BH01 0313 31 103030 34 30
> BL-HD06B-BH06 1805 08 583030 35 31
> BL-HD06B-BH06 1805 07 543030 35 31
> BL-HD07B-BH06 1801 42 233031 38 30
> BL-HD07B-BH06 1801 43 283031 38 30
> BL-HD07B-BH01 0712 22 223030 f3 31
> BL-HD08B-BH01 0713 51 383030 f3 30
> BL-HD08B-BH01 1912 45 323031 38 30
> BL-HD08B-BH01 0713 52 423030 f3 30
> BL-HD09B-BH01 0713 05 383030 f3 31
> BL-HD09B-BH01 1705 34 483031 39 30
> BL-HD09B-BH01 0713 04 333030 f3 31
> BL-HD10B-BH06 1809 43 453030 35 30
> BL-HD10B-BH06 1805 45 163031 39 30
> BL-HD10B-BH01 2019 22 063030 30 31
> BL-HD11B-BH01 1706 05 363030 31 31
> BL-HD11B-BH01 1706 06 413030 31 31
> BL-JB90B-BH06 1714 45 003031 31 30
> BL-JB90B-BH06 1812 29 423032 30 30
> BL-JB90B-BH06 1714 46 033031 31 30
> BL-JB91B-BH06 1812 43 593030 39 30
> BL-JB91B-BH01 1312 01 213030 30 30
> BL-JB92B-BH01 1516 03 313030 36 30
> BL-KS73A-BH06 0409 36 403030 30 30
> BL-N596F-BH01 0310 09 003031 31 30
> BL-N596G-BH07 0318 02 083439 36 31
> BL-N605G-BH02 1301 12 583032 30 31
> BL-N631H-BH12 1615 41 363031 33 30
> BL-N631I-BH01 1910 28 323030 35 30
> BL-N633G-BH12 1103 48 403030 32 30
> BL-N633H-BH03 0514 21 503030 33 30
> BL-N634G-BH07 0317 00 263030 31 30
> BL-N638F-BH12 0519 13 383031 32 31
> BL-N639H-BH03 2602 32 503030 39 30
> BL-N640G-BH03 2600 59 573030 31 30
> BL-N640G-BH03 2604 41 363030 34 30
> BL-V444B-BH12 1302 51 003031 34 30
> BL-Y472B-BH03 2008 21 383031 32 31
> BL-Y982D-BH03 0520 02 573031 39 30
> BL-Y982D-BH07 0315 48 313030 37 31
> BL-Z934D-BH04 1004 16 133030 33 30
> ---
>  MIN01 0200 00 003030 30 30
>  MAX12 2620 59 593439 f3 31
>NVALS08 1214 22 210204 0b 02
>   OR17 3f3f 7f 7f343b ff 31
>  AND00 0000 00 003030 30 30
>
>
> Key
> MIN   is the minimum value seen
> MAX   is the maximum value seen
> NVALS is the count of unique values seen
> ORvalues have a 1 for every bit that is ever 1
> AND   values have a 1 for every bit that is always 1
>
> 
>
> Some interesting things to note:
>
>   * only some diskettes have 81st cylinder data.  They tend to be the
> later releases (1985 and later).  (My table simply omits those
> diskettes I have without 81st cylinder data).
>   * different copies of the same diskette (e.g., BL-HD11B-BH) have
> slightly different values, so it doesn't appear that these value
> encode some 

Re: PCI floppy controller

[Warner Losh via cctalk]

I'd gotten the impression that there was some angst in its community of
users
over something. I can't find now where I'd gotten that impression, though.
Mine
works great, and I've had no issues with it. They've been helpful when I've
reported
trouble I had using it, but it was pilot error on my part and they helped
me understand
what the reports and output of the tools were actually telling me.

Warner

On Sat, Apr 23, 2022 at 12:04 AM Tom Hunter  wrote:

> I am curious about your comment about "kryoflux going south".
> I did not hear about any problems. Could you please elaborate?
> I got mine about 2 or 3 years ago and it did everything I needed at the
> time, but haven't used it since.
>
> Thanks
> Tom
>
>
> On Sat, Apr 23, 2022 at 9:19 AM Warner Losh via cctalk <
> cctalk@classiccmp.org> wrote:
>
>> On Fri, Apr 22, 2022 at 7:07 PM Bill Gunshannon via cctalk <
>> cctalk@classiccmp.org> wrote:
>>
>> >
>> > As another person with a desire to be able to read/write/create
>> > disks of different sizes and formats I have found this interesting.
>> >
>> > So the question, then
>> >
>> > How hard would it be to make a floppy disk interface using an Arduino
>> > or even RasberryPi?  If you could do that the choices of interface
>> > to a PC opens up quite a bit.  It would never be like having a floppy
>> > hanging off the PC, but then none of the formats I am interested in
>> > are grounded in the PC anyway and utilities would need to be written
>> > to access them.
>> >
>> > comments?
>> >
>>
>> Isn't that what Greaseweasel  and similar do? I have a kyroflux that I use
>> to read floppies on my macbook. It can write as well and understands a ton
>> of formats. Greaseweasel is more available and supported (I got my
>> kyroflux
>> before things went south, so wouldn't recommend others get one these
>> days).
>>
>> Warner
>>
>

Re: PCI floppy controller

[Warner Losh via cctalk]

On Fri, Apr 22, 2022 at 7:07 PM Bill Gunshannon via cctalk <
cctalk@classiccmp.org> wrote:

>
> As another person with a desire to be able to read/write/create
> disks of different sizes and formats I have found this interesting.
>
> So the question, then
>
> How hard would it be to make a floppy disk interface using an Arduino
> or even RasberryPi?  If you could do that the choices of interface
> to a PC opens up quite a bit.  It would never be like having a floppy
> hanging off the PC, but then none of the formats I am interested in
> are grounded in the PC anyway and utilities would need to be written
> to access them.
>
> comments?
>

Isn't that what Greaseweasel  and similar do? I have a kyroflux that I use
to read floppies on my macbook. It can write as well and understands a ton
of formats. Greaseweasel is more available and supported (I got my kyroflux
before things went south, so wouldn't recommend others get one these
days).

Warner

Re: PCI floppy controller

[Warner Losh via cctalk]

On Fri, Apr 22, 2022, 12:25 PM Grant Taylor via cctalk <
cctalk@classiccmp.org> wrote:

> On 4/22/22 11:46 AM, Warner Losh via cctalk wrote:
> > By the time there were PCI Adaptec cards, there was no longer a floppy
> > controller on them that I ever saw. As others have pointed out,
> > though, it would need special drivers and/or BIOS support because
> > PCI devices mixed poorly with ISA DMA that the floppy was built on.
>
> I'd swear that I've used a PCI Adaptec card with a floppy controller.
> 2942 comes to mind.
>

I thought the 2942 had 2 SCSI channels, I thought. Google can't find a
definitive answer but all the 2940 cards on eBay didn't have obviously
unstuck parts for a floppy. The aha 1540 did...

Warner

-- 
> Grant. . . .
> unix || die
>

Re: PCI floppy controller

[Warner Losh via cctalk]

On Thu, Apr 21, 2022 at 7:54 PM Grant Taylor via cctalk <
cctalk@classiccmp.org> wrote:

> On 4/21/22 5:47 PM, Charles Dickman via cctalk wrote:
> > Were there ever any floppy controllers for the (parallel) PCI bus?
>
> Didn't some of the Adaptec SCSI cards have a floppy controller on them?
>
> Could that be made to work?
>

The AHA 15x2 cards had a floppy controller. It was a nothing special
floppy controller that you'd otherwise find bundled on a multi-function
card. These cards were ISA. The details of which controller varied over
time, IIRC, but I had one of these since I didn't have a multi-function
card in my 486 DX2-66 that I started my PC journey with (it took me
a while to give up on the Rainbow).

The AHA 1742 cards had a floppy controller on them as well. Same
deal: but this was a EISA card.

I'm told the AHA1642 was similar, but I've not seen a microchannel
version of the card.

By the time there were PCI Adaptec cards, there was no longer a
floppy controller on them that I ever saw. As others have pointed
out, though, it would need special drivers and/or BIOS support because
PCI devices mixed poorly with ISA DMA that the floppy was built on.

Warner

Re: Retro networking / WAN communities

[Warner Losh via cctalk]

On Mon, Apr 11, 2022, 4:39 PM Grant Taylor via cctalk 
wrote:

> On 4/11/22 1:59 PM, Lars Brinkhoff via cctalk wrote:
> > For your consideration:
> >
> > - Arpanet (NCP)
>
> Is that "NCP" the same NCP that's in ancient BSDs?  Or is it a term
> collision?
>

NCP was the forerunner of TCP/IP. Net Unix had it as its supported protocol
and that was old enough that BSD had at least one implementation.

Warner

> - Tymnet
>
> I think of Tymnet as a service and not as much as a protocol.  Though
> maybe it implies a protocol and I'm unaware of it.
>
> > - Chaosnet
>
> Ya.  Isn't Chaosnet mostly used in LISP machines?  --  This seems fairly
> far afield for my interest.
>
> > - PUP
>
> Maybe.  It also seems fairly afar afield for what I can get my hands on
> and / or emulate.
>
> > - UUCP
>
> There.  Ding that.
>
> I'm even pontificating a custom UUCP configuration that is specific to
> my user.  As in /not/ a system wide version.
>
>
>
> --
> Grant. . . .
> unix || die
>

Re: Data recovery (was: Re: SETI@home (ca. 2000) servers heading to salvage)

[Warner Losh via cctalk]

That's what a sanitize operation does. It forgets the key and reformats the
metadata with a new key.

Also, with SSDs, any erase block that's erased is going to not have any
data that's recoverable.
First, the erase voltage is huge, moving the cell to a negative
voltage (the only abode that's
negative is all 1's). Next, the microprocessor in the NAND dies are going
to 'pre-program' the
abodes to a uniform negative voltage that's easier to program when you
start putting data on
the ages. Finally, most (nearly all) NAND dies have randomization circuitry
that randomizes the
data after you send it to the drive (or whitens it) that you'll need the
psuedorandom seed to read
it back coherently.

The problem, though, comes with erase blocks that have broken and no longer
erase. These
retired blocks can contain data still, but given the
randomization/whitening and/or some
global encryption key, the data can be difficult or impossible to
meaningfully recover, even
when other pathologies don't degrade the block more (not least is aging: if
the block was
retired a long time ago, the NAND cells, being tiny capacitors, will bleed
the charge off to
the erased state +/-).

As with most forms of data destruction, putting a metal spike through the
NAND dies
themselves would likely suffice :) But it is a tad destructive

Warner

On Mon, Apr 4, 2022 at 8:34 AM Chris Zach via cctalk 
wrote:

> Good data Paul! SSD's are a different beast, if you're going to put data
> on them that you do not want recovered I would recommend encrypting the
> drive before using it, then when done delete/destroy the key. That
> should turn your drive into a useless (but format-able) chunk of silicon.
>
> C
>
> On 4/4/2022 8:28 AM, Paul Koning via cctalk wrote:
> > SSDs are a different story entirely because there you don't write over
> the actual data; instead a write updates internal metadata saying where the
> most recent version of block number xyz lives.  So, given that you tend to
> have a fair amount (10 or 20 percent if not more) of "spare space" in the
> SSD, previous data are likely to be hanging around.  I suspect if you write
> long enough you could traverse all that, but how to do that depends on the
> internals of the firmware.  That's likely to be confidential and may not
> even be reliably known.
> >
> > There are SSD SEDs.  If designed correctly those would give you
> cryptographically strong security and "instant erase".  Not all disk
> designers know how to do these designs correctly.  If I needed an SED (of
> any kind) I'd insist on a detailed disclosure of its keying and key
> management.  Prying that out of manyfacturers is hard.  I've done it, but
> it may be that my employer's name and unit volume was a factor.
>

Re: Looking for computer and individual to read old floppy disks

[Warner Losh via cctalk]

On Fri, Mar 11, 2022, 8:34 PM Fred Cisin  wrote:

>  I got more details from the guy with the disks.  They are apparently
>  "360K" PC floppies with XYWRITE files, and he wants to load the file
>  contents into a "modern"? word processor.  So hopefully, somebody can
>  help him, with a simple COPY *.*, and I think that he now understands
>  that he might also need to get back a copy of XYWRITE to turn the
>  file content into something usable.
>
> >>> It was mentioned that he would pay someone to do this.  Why not just
> >>> tell him to buy a $20 USB Floppy from Amazon and copy them himself?
>
> > On Fri, Mar 11, 2022 at 7:25 PM Fred Cisin via cctalk <
> cctalk@classiccmp.org>
> > wrote:
> >> 5.25" USB floppies seem to be scarce now!
> >> I didn't do any serious searching, but neither Amazon nor eBay showed
> any
> >> obvious (on first page) hits.
> >> Some of the early USB drives, even if 3.5", MIGHT separate controller
> and
> >> drive enough to be modifiable, . . .
> >> I would GUESS that the "modern" ones are too "integrated".
>
> On Fri, 11 Mar 2022, Warner Losh wrote:
> > There are no 5.25" USB floppies. Well, not 100% true (there are values
> > in the identifier strings that tell you it's a 1.2MB floppy vs a 1.44MB
> > floppy), but as a practical matter, you can't find them. I've looked and
> > gave up... That's how I wound up with my kyroflux + TEAC drive (though a
> > greaseweasel is a better choice these days)...
> >
> > If these are the old 360k diskettes, then you'd be out of luck the USB
> > route.. But an imager would be on the order of $30 for the greaseweasel,
> > or similar, and another $40 for a working 5.25" drive and a few hours of
> > your time to set it up and figure it all out... So anybody copying the
> > disks for < ~$100 or $150 would be cost effective for this person...
>
> If somebody DID make a 1.2M USB floppy, it would seem likely that they
> OUGHT TO include the 360K option within it, . . .
>

It ought to... but that's not defined in the standard...

But, if 1.2M USB drives exist, or ever existed, they're R@RE
> I HOPE that the USB 1.4M drives handle 720K, . . .
>

That's what I hoped when I bought it, but no joy. Even trying nonstandard
format values was no help. It would only read 1.44MB.

Warner


> The harder part is converting XYWRITE files into something more mordern...
>
> In his further detail private message, He seemd to understand that he
> might have to get a replacement copy of XYWRITE (he said that he gave his
> to Goodwill a few months ago), and do a load and SAVE-AS for each file.
>
>
> Yes, it was always fun trying to explain to people that COPYing the
> Wordstar file was NOT the cause of the "corruption of the last letter of
> each word".  Fortunately, THAT one was trivial to deal with.  I don't know
> anything about the file structure of XYWRITE.
>
>
> [This reply was delayed by a power failure]
> --
> Grumpy Ol' Fred ci...@xenosoft.com
>

Re: Looking for computer and individual to read old floppy disks

[Warner Losh via cctalk]

On Fri, Mar 11, 2022, 8:04 PM Chuck Guzis via cctalk 
wrote:

> On 3/11/22 18:32, Warner Losh via cctalk wrote:
>
> > There are no 5.25" USB floppies. Well, not 100% true (there are
> > values in the identifier strings that tell you it's a 1.2MB floppy vs
> > a 1.44MB floppy), but as a practical matter, you can't find them.
> > I've looked and gave up... That's how I wound up with my kyroflux +
> > TEAC drive (though a greaseweasel is a better choice these days)...
> >
>
> Not completely true--in the old USB 1.0 days, there were a very few
> USB-to-floppy bridges that could talk 5.25' 250Kbit/sec-speak.  SMC had
> one such and I suspect that multi-chip implementations were also available
>

Yea, that's why I said almost. The standard interface just allows an LBA
and only certain fixed formats are defined that are very high level. This
isn't conducive to different formats, data rates, etc. Unless there are
nonstandard endpoints, all you can read is the 1.2MB diskettes... I spent a
lot of time making this work with the 1.44mb 3.5" drive on FreeBSD. It
can't even read 720k diskettes, at least the drive I had...

But given that few new people understand anything that's not Windows, it
> would be a futile effort, I suspect.
>

True. It's likely easier to use an imager and TEAC if they are 360k
diskettes... or pay someone :)

Warner

All the best,
> Chuck
>

Re: Looking for computer and individual to read old floppy disks

[Warner Losh via cctalk]

On Fri, Mar 11, 2022 at 7:25 PM Fred Cisin via cctalk 
wrote:

> >> I got more details from the guy with the disks.  They are apparently
> >> "360K" PC floppies with XYWRITE files, and he wants to load the file
> >> contents into a "modern"? word processor.  So hopefully, somebody can
> help
> >> him, with a simple COPY *.*, and I think that he now understands that
> he
> >> might also need to get back a copy of XYWRITE to turn the file content
> into
> >> something usable.
>
> On Fri, 11 Mar 2022, Bill Gunshannon via cctalk wrote:
> > It was mentioned that he would pay someone to do this.  Why not just
> > tell him to buy a $20 USB Floppy from Amazon and copy them himself?
>
> 5.25" USB floppies seem to be scarce now!
> I didn't do any serious searching, but neither Amazon nor eBay showed any
> obvious (on first page) hits.
>
> Some of the early USB drives, even if 3.5", MIGHT separate controller and
> drive enough to be modifiable, . . .
> I would GUESS that the "modern" ones are too "integrated".
>

There are no 5.25" USB floppies. Well, not 100% true (there are values in
the
identifier strings that tell you it's a 1.2MB floppy vs a 1.44MB floppy),
but as
a practical matter, you can't find them. I've looked and gave up... That's
how
I wound up with my kyroflux + TEAC drive (though a greaseweasel is a
better choice these days)...

If these are the old 360k diskettes, then you'd be out of luck the USB
route..
But an imager would be on the order of $30 for the greaseweasel, or
similar, and
another $40 for a working 5.25" drive and a few hours of your time to set
it up and
figure it all out... So anybody copying the disks for < ~$100 or $150 would
be cost
effective for this person...

The harder part is converting XYWRITE files into something more mordern...

Warner

Re: Information about an unknown IC

[Warner Losh via cctalk]

On Thu, Feb 24, 2022, 12:47 PM Clemar Folly via cctalk <
cctalk@classiccmp.org> wrote:

> This chip is from a cartridge for the Atari 2600. The board is not mine.
> I'm trying to help identify the IC.
>
> It's the PCB of the AtariAge post.
>
> I had already looked in the Texas data book and found nothing.
>

Then it is almost certainly a custom ROM of some flavor

Warner


Thanks.
>
> On Thu, Feb 24, 2022 at 3:44 PM jim stephens via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > The thread with the photograph had an Ebay source for the part.
> >
> > https://www.ebay.com/itm/151010204380
> >
> > doesn't help with function, or with the solder blob jumper purpose (or
> > booboo) but can get the part for some amount if they ship to Brazil.
> >
> >
> > On 2/24/2022 10:24 AM, Bill Degnan via cctalk wrote:
> > > I have a pretty complete set of TI books, there are no chips that begin
> > > with TB-n.  There are many chips that start with T, but none that
> > match
> > > your chip ID
> > >
> > > On Thu, Feb 24, 2022 at 1:21 PM Paul Koning via cctalk <
> > > cctalk@classiccmp.org> wrote:
> > >
> > >>
> > >>> On Feb 24, 2022, at 1:16 PM, Brent Hilpert via cctalk <
> > >> cctalk@classiccmp.org> wrote:
> > >>> On 2022-Feb-24, at 8:29 AM, Clemar Folly via cctalk wrote:
> >  I'm looking for information about Texas Instruments TB-759933 IC.
> > 
> >  Does anyone have the datasheet or any other information about this
> IC?
> > >>>
> > >>> A search shows this question was posted over here, with a picture:
> > >>>
> > >>
> >
> https://atariage.com/forums/topic/331769-unknown-cart-ic-please-i-need-some-help/
> > >>
> > >> Wow, that's a sorry looking board.  It looks like it was assembled by
> > >> someone using a soldering gun and acid-core solder.  But most plumbers
> > >> would do better work than that.
> > >>
> > >>  paul
> > >>
> > >>
> > >>
> >
> >
>

Re: DEC VT52 CRT anode connection

[Warner Losh via cctalk]

On Wed, Feb 23, 2022, 10:05 PM Chuck Guzis via cctalk 
wrote:

> On 2/23/22 18:17, Doug Jackson via cctalk wrote:
> > Hmm - Depends on where that pesky ground connection is put :-)  (Duck)
>
> Well, if you stand on your head whilst soldering it in, it's all good! :)
>

True, but also helps if it doesn't get hot enough to need a heat sync :).

Warner

>