My RK05's are acting up again. They first acted like this when I was
bringing them up after a 30 year nap. The symptom then was that one of the
Maindecs for disk testing would complain that it couldn't write because a
CE disk was in the drive! (Which brings up the quesiton: Why would it
think that? Is there a wire on the disk interface bus that is pulled down
when a either a CE disk (how??) or else the disk alignment suitcase is
Anyway, now that I can run RKUTIL I have a new problem that just happened
this weekend. I can no longer select option 4 (read/write test). It
simply reprints the prompt, no error message at all! I assume this is the
CE present problem rearing it's ugly head again. RKTUTIL worked fine up
until this weekend.
Anyway, I'd like to look at the RKUTIL source but can't find it anywhere.
Does anyone have a pointer to this?
Also, if anyone knows what triggers the CE present condition I'd like to
know about that too.
i recently got a MAI Basic Four 210 from the Netherlands. The CPU now
powers up, have not yet tried the 14" Piram harddisk.
I would like to know if the CPU is working. It seems to be based on a
microdata 1600 but equiped with dram and cmos ROMs.
The machine has switches were it can be set to boot standard/alternate
>from disk, tape or from a serial terminal. Since
the tape drive has a capstan roller transformed to liquid and i have not
yet tested the disk i would like to know how to
boot from a terminal.
I have not yet read the microcode proms nor have i checked if they are
soldered or on sockets.
Does someone out there have access to the cpu manuals that are stated in
the service manual ?
1300 CPU Technical Manual, Document No. SM 1200
M1300 Series CPU Organisation and Description Reference Manual
Pictures from the machine are here:
and the manuals are on bitsavers in pdf/mai, the service manual also
contains the cpu schematics, the ones for the tape
controller and the disk controller are included in the tape / disk
What do you think are the chances to get the disk up and running. (since
i have no tapes of other software)
All seems to be stored dry, no rust, nor a lot of dirt in the machine.
Seemd to be powered on the last time more than 15 years ago.
On Tue, May 27, 2014 at 10:00 AM, <cctalk-request at classiccmp.org> wrote:
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> Message: 7
> Date: Tue, 27 May 2014 00:05:43 -0700
> From: Josh Dersch <derschjo at gmail.com>
> To: General Discussion: On-Topic and Off-Topic Posts
> <cctalk at classiccmp.org>
> Subject: Re: Catch and Halt Fire - Drama set in early days of personal
> Message-ID: <53843947.3090006 at gmail.com>
> Content-Type: text/plain; charset=UTF-8; format=flowed
> On 5/26/2014 11:03 PM, Eric Smith wrote:
> > On Mon, May 26, 2014 at 4:12 PM, Josh Dersch <derschjo at gmail.com> wrote:
> >> Yes, it's insane to think that someone could be intelligent *and* female
> >> *and* have fashion sense at the same time.
> >> God forbid, especially in this industry.
> > I'm reasonably certain that Sellam was talking about how things
> > were back in the early 1980s, not how they should have been, or how they
> > might be now, or how we might want the early 1980s portrayed in 21st
> > century television programs.
> I've no doubt that women were in the minority in the computer biz in the
> 1980s (as they remain today). I do take umbrage with Sellam's
> supposition that there were no women at all with technical knowledge (or
> if there were, they were all apparently ugly) -- this is demonstrably
> untrue and it seems an odd point to bring up as a criticism of the show
> (I mean, it has so many other flaws that he didn't even see, since he
> admits to only watching 3 minutes of it...). Were there are lot of
> women in the industry? No. Does the show have a woman in it? Yep. Is
> this particularly unrealistic? Nah.
> (Really, I'd like to give the show a chance; I feel like I'm
> experiencing what every doctor or lawyer goes through when watching a
> medical or legal drama on TV or in the theater...)
> At any rate, just me spouting off my mouth when I ought best have said
> nothing at all :).
> - Josh
> > As with most generalizations, perhaps Sellam's wasn't 100% accurate, but
> > was damn close. Unfortunately.
Yes, I remember the early 1980s and working in a small shop that did
primarily what we would now call embedded systems with 6800
microprocessors, but also some larger business systems based on
minicomputers. We had a very attractive young woman who did programming on
the business stuff, and we insensitive males referred to her (out of her
earshot) as "software". She dressed well, she was sweet and friendly (and
obviously, tolerant!) and she could code.
Back further, in the 1970s there was a young woman in my FORTRAN class I
dated briefly. She was also on the high school swim team, and I started
attending meets. :-)
Yes, things were more gender-imbalanced than they are today, but making any
gender-based assumptions (appearance, fashion sense, etc.) about the women
who *were* involved in the industry is not particularly useful, meaningful
or accurate. As I remember things....
Ian S. King, MSIS, MSCS
The Information School
University of Washington
Madness takes its toll - please have exact change.
I've been reading the SIMH TAP file specification and there's something
that's not clear to me. Perhaps someone can volunteer their knowledge.
I've got a tape where about half the records (blocks) are an odd number
of bytes long. The SIMH document says that a block is padded to an even
number of bytes in this case. However, it doesn't say if the record
length (32-bit) word is adjusted to reflect this--or if the byte count
is rounded up to the nearest even byte.
It seems to me that the former would be the way to go, but I'm not sure.
If the latter course is taken, the information that the block is an
odd number of bytes long is gone.
Does anyone know for certain?
> Interesting Minis with displays...
There are a lot listed in the Communications of the ACM journals.
Taking a random May 1967.....NCR 315 family, SDS (Sigma 7,5), Burroughs 500,
Univac 1108...at least to get an idea of what systems look like so you can
hunt down the terminal/vector/display types.
Don't forget plotters and terminal printers. What percent used these as the
primary display? Or is that not what you want?
From: Pontus Pihlgren <pontus at Update.UU.SE>
> There was quite a bit actually. The LINC, LINC-8, PDP-1 and
> PDP-12 all had vector displays. There was also an add-on for the
> original PDP-8 and PDP-6, display 340 or something like that.
No, they were point displays, no capability to draw a vector.
The LINC, LINC-8 and PDP-12 at least had character generators
that would draw a 2 x 6 grid of dots from a 12-bit word. Two
of those grids would draw a 4x6 dot matrix character on the
screen. So, a character could be drawn with a small number
From: Martin Goldberg<wgungfu at gmail.com>
Hey guys, we're on the next phase of our paper we're presenting at a
conference soon and are hoping to collect a listing of 1960s era mainframes
and minis that had CRT displays available for them. We're obviously already
aware of the various DEC models released in the 60s that had them, but
we're looking for other brands now.
Don't forget the LINC, a major feature was the character
It could also display limited graphics (due to CPU speed) and
waveforms. The early LINCs were made with DEC parts, but
were assembled by grad students at a summer session.
We had a PDP-5 which had a very similar system on it that
made by DEC, or at least it seemed to be factory-made.
I have started putting together some overview videos documenting my classic
HP3000. Purpose is to just give people a flavor of what classic
mini-computing was like in the 1970s/1980s. My first video on the HP7974
tape drive is posted at Youtube: http://youtu.be/mDnNZuDNJfg
Production values are *low* - just me riffing on the item, shot with my
cell phone camera, and edited with iMovie. I just want to get some done
while I have time. Take a look, suggestions appreciated.