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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
@ 2021-09-17 20:18 Noel Chiappa
  2021-09-17 20:47 ` Clem Cole
  0 siblings, 1 reply; 17+ messages in thread
From: Noel Chiappa @ 2021-09-17 20:18 UTC (permalink / raw)
  To: tuhs; +Cc: jnc

    > From: Clem Cole

    > The KS11 MMU for the 11/20 was built by CSS ... I think Noel has done
    > more investigation than I have.

I got a very rough description of how it worked, but that was about it.

    > I'm not sure if the KS11 code is still there. I did not think so.

No, the KS11 was long gone by later Vn. Also,I think not all of the -11/20
UNIX machines had it, just some.

    > The V1 work was for a PDP-7

Actually, there is a PDP-11 version prior to V2, canonically called V1.
The PDP-7 version seems to be called 'PDP-7 UNIX' or 'V0'.


    > I'm fairly sure that the RK05,  used the RK11-D controller.

Normally, yes. I have the impression that one could finagle RK03's to work on
the RK11-D, and vice versa for RK05's on the RK11-C, but I don't recall the
details. The main difference between the RK11-C and -D (other then the
implementation) was that i) the RK11-C used one line per drive for drive
selection (the -D used binary encoding on 3 lines), and ii) it had the
'maintenance' capability and register (al omitted from the -D).

    > The difference seems to have been in drive performance.

Yes, but it wasn't major. They both did 1500RPM, so since they used
the same pack format, the rotational delay, transfer rate, etc were
identical. The one peformance difference was in seeks; the
average on the RK01 was quoted as 70 msec, and 50 msec on the
RK05.


    > Love to see the {KT11-B prints] and if you know where you found them.

They were sold on eBait along with an -11/20 that allegedly had a KT11-B. (It
didn't; it was an RK11-C.) I managed to get them scanned, and they and the
minimal manual are now in Bitsavers. I started working on a Tech Manual for
it, but gave up with it about half-way done.

    > I wonder if [our V1 source] had the KS-11 stuff in it. 

No; I had that idea a while back, looked carefully, our V1 listings
pre-date the KS11.


    > From: Roland Huisman

    > There is a KT11B paging option that makes the PDP11/20 a 18 bit
    > machine.

Well, it allows 2^18 bytes of main memory, but the address space of the
CPU is still2^16 bytes.

    > It looks a bit like the TC11 DECtape controller.

IITC, it's two backplanes high, the TC11 is one. So more like the RK11-C...
:-)

    > I have no idea how it compares to the later MMU units from the
    > software perspective.

Totally different; it's real paging (with page tables stored in masin
memory). The KT11-B provides up to 128 pages of 512 bytes each, in both Exec
and User mode. The KT11-C, -D etc are all segmentation, with all the info
stored in registers in the unit.

    > I wonder is there is some compatibility with the KT11-B [from the KS11]

I got the impression that the KS11 was more a 'base and bounds' kind
of thing.

	Noel

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 20:18 [TUHS] Unix for PDP11/20 w/o mmu or paging option Noel Chiappa
@ 2021-09-17 20:47 ` Clem Cole
  0 siblings, 0 replies; 17+ messages in thread
From: Clem Cole @ 2021-09-17 20:47 UTC (permalink / raw)
  To: Noel Chiappa; +Cc: TUHS main list

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On Fri, Sep 17, 2021 at 4:19 PM Noel Chiappa <jnc@mercury.lcs.mit.edu>
wrote:

>    I got the impression that the KS11 was more a 'base and bounds' kind of
> thing.
>
Ditto.  I was under the impression it was modeled after the KA10 scheme.  I
don't remember who told me that, probably somebody from CSS, but I have no
idea whom.  As I think you remember when you asked about it a while ago, I
sent some probes to a few of folks from the 11 group but all of them
disavowed any knowledge of it.

One of the questions I always had was since M[TF]P[IDS] instructions were
not created until the 40 and 45 class processors, how did Ken get the
information to/fr the other address space.   I >>think<< the KT has a funky
memory window (that I never really looked into in any detail), I assume
the KS must have done something similar.
ᐧ

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 19:51     ` Brantley Coile
  2021-09-17 20:07       ` Clem Cole
@ 2021-09-17 21:21       ` Phil Budne
  1 sibling, 0 replies; 17+ messages in thread
From: Phil Budne @ 2021-09-17 21:21 UTC (permalink / raw)
  To: clemc, brantley; +Cc: tuhs

I was commenting based on the Boot Procedures man page on pg 5 of the pdf at:
https://www.bell-labs.com/usr/dmr/www/pdfs/man71.pdf
on dmr's "Unix Manual, first edition" page:
https://www.bell-labs.com/usr/dmr/www/1stEdman.html

which makes no reference to the rk disk, but does talk about loading up
initial files.

The page for init (pdf p.11) mentions that the usr directory is
mounted from the rk disk.

The rf0 page (pdf p3) at
https://www.bell-labs.com/usr/dmr/www/pdfs/man41.pdf
says
  "writing is inherently very dangerous since a file system resides there"

The description of seek on the special files really slapped me in the
face for the first time!

The tty page in the man41 file ever so slightly advances my theory
that the interrupt character on the PDP-7 console (0176 or rather 0376)
could have been generated by the "ALT MODE" key on the console Teletype.

But regarding memory management, I foolishly put my foot in the gopher
hole of assumption that the earliest kernel on hand required the
mystery MMU, without verifying by reading the code, and forgetting
that "editions" refer to dates the manual was published, and that the
fragmentary fossil record that is the earliest surviving code (which
was in a constant state of evolution) doesn't align with the manuals.

Mea culpa, for adding any confusion!

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 19:51     ` Brantley Coile
@ 2021-09-17 20:07       ` Clem Cole
  2021-09-17 21:21       ` Phil Budne
  1 sibling, 0 replies; 17+ messages in thread
From: Clem Cole @ 2021-09-17 20:07 UTC (permalink / raw)
  To: Brantley Coile; +Cc: TUHS main list

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On Fri, Sep 17, 2021 at 3:51 PM Brantley Coile <brantley@coraid.com> wrote:

> swplo was past the root file system.
>
That is v5 and v6 for sure, but I'm not so sure about that the earlier
systems.     I did a quick peek earlier today and in the v1 code, it seems
to be hardcoded but I can say I sat and read it in detail.
ᐧ

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 19:43   ` Clem Cole
@ 2021-09-17 19:51     ` Brantley Coile
  2021-09-17 20:07       ` Clem Cole
  2021-09-17 21:21       ` Phil Budne
  0 siblings, 2 replies; 17+ messages in thread
From: Brantley Coile @ 2021-09-17 19:51 UTC (permalink / raw)
  To: Clem Cole; +Cc: TUHS main list

swplo was past the root file system.

> On Sep 17, 2021, at 3:43 PM, Clem Cole <clemc@ccc.com> wrote:
> 
> (the genesis of the tiny root partition?),
> I thought the original system just swapped to it, no mounted FS on it, but unless someone knows for sure, it means staring at Ken's assembler listings for V1 that Warner mentioned earlier.   
> 


^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 18:28 ` Phil Budne
@ 2021-09-17 19:43   ` Clem Cole
  2021-09-17 19:51     ` Brantley Coile
  0 siblings, 1 reply; 17+ messages in thread
From: Clem Cole @ 2021-09-17 19:43 UTC (permalink / raw)
  To: Phil Budne; +Cc: TUHS main list

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On Fri, Sep 17, 2021 at 2:51 PM Phil Budne <phil@ultimate.com> wrote:

> The earliest Unix running on the 11/20 requires not only the custom MMU,
> but also a fixed-head disk

Right, a 4Mbyte RF11/RS11 which Ken refers to as /dev/drum in this code.
That lived for a pretty long time - at least thru the Sixth edition, IIRC.



> (the genesis of the tiny root partition?),

I thought the original system just swapped to it, no mounted FS on it, but
unless someone knows for sure, it means staring at Ken's assembler listings
for V1 that Warner mentioned earlier.



> so I agree with Noel that MINI-UNIX and LSX, while not "historically
> correct" for your hardware are a good fit, and that
> building a working system on simulated hardware would likely be the easiest
> route.
>
> Phil
>
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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 15:35 Noel Chiappa
@ 2021-09-17 18:28 ` Phil Budne
  2021-09-17 19:43   ` Clem Cole
  0 siblings, 1 reply; 17+ messages in thread
From: Phil Budne @ 2021-09-17 18:28 UTC (permalink / raw)
  To: tuhs

The earliest Unix running on the 11/20 requires not only the custom
MMU, but also a fixed-head disk (the genesis of the tiny root
partition?), so I agree with Noel that MINI-UNIX and LSX, while not
"historically correct" for your hardware are a good fit, and that
building a working system on simulated hardware would likely be the
easiest route.

Phil

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 16:14         ` Clem Cole
@ 2021-09-17 16:44           ` Roland via TUHS
  0 siblings, 0 replies; 17+ messages in thread
From: Roland via TUHS @ 2021-09-17 16:44 UTC (permalink / raw)
  To: TUHS main list

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There is a KT11B paging option that makes the PDP11/20 a 18 bit machine. It looks a bit like the TC11 DECtape controller. I've got the schematics from the internet. But I have no idea how it compares to the later MMU units from the software perspective.Love to see them and if you know where you found them. 
Al has put them online once. 
http://bitsavers.trailing-edge.com/pdf/dec/pdp11/1120/KT11-B_EngrDrws_Feb72.pdfhttp://bitsavers.trailing-edge.com/pdf/dec/pdp11/1120/KT11-B_OD_Apr71.pdf

The V1 work was for a PDP-7 and is before the first 11/20 was secured.  The point is that I think there is a hole in the the SW we have.
I just looked again at what Warren has -- it is the 11/20 assembler code that Dennis scanned.  I have forgotten that we still had that.   I wonder if it had the KS-11 stuff in it.   I'll have to peek  

I wonder is there is some compatibility with the KT11-B
Regards, Roland

rrrjj
  

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 16:13       ` Warner Losh
@ 2021-09-17 16:17         ` Clem Cole
  0 siblings, 0 replies; 17+ messages in thread
From: Clem Cole @ 2021-09-17 16:17 UTC (permalink / raw)
  To: Warner Losh; +Cc: tuhs

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On Fri, Sep 17, 2021 at 12:13 PM Warner Losh <imp@bsdimp.com> wrote:

>
> We have printouts for V0. And the kernel for V1 with bits and pieces in
> the V2 to V3 timeframe that folded into the Unix-Jun72 efforts.
>
Right.  Need to look to see if the KS11  support was in there.
ᐧ

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 16:04       ` Roland via TUHS
@ 2021-09-17 16:14         ` Clem Cole
  2021-09-17 16:44           ` Roland via TUHS
  0 siblings, 1 reply; 17+ messages in thread
From: Clem Cole @ 2021-09-17 16:14 UTC (permalink / raw)
  To: Roland, TUHS main list

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On Fri, Sep 17, 2021 at 12:04 PM Roland via TUHS <tuhs@minnie.tuhs.org>
wrote:

>
> There is a KT11B paging option that makes the PDP11/20 a 18 bit machine.
> It looks a bit like the TC11 DECtape controller. I've got the schematics
> from the internet. But I have no idea how it compares to the later MMU
> units from the software perspective.
>
Love to see them and if you know where you found them.


> The V1 work was for a PDP-7 and is before the first 11/20 was secured.
> The point is that I think there is a hole in the the SW we have.
>
I just looked again at what Warren has -- it is the 11/20 assembler code
that Dennis scanned.  I have forgotten that we still had that.   I wonder
if it had the KS-11 stuff in it.   I'll have to peek
ᐧ

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 15:32     ` Clem Cole
  2021-09-17 16:04       ` Roland via TUHS
@ 2021-09-17 16:13       ` Warner Losh
  2021-09-17 16:17         ` Clem Cole
  1 sibling, 1 reply; 17+ messages in thread
From: Warner Losh @ 2021-09-17 16:13 UTC (permalink / raw)
  To: Clem Cole; +Cc: tuhs

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On Fri, Sep 17, 2021 at 9:32 AM Clem Cole <clemc@ccc.com> wrote:

> FYI:  The KS11 MMU for the 11/20 was built by CSS and was not on the
> product list as it were. To my knowledge, no hardware or prints of it
> survive.    I've been told it was much more similar to the MMU in the KA10
> than the scheme eventually done for the 11/45/55/70 and the 11/40 class
> systems - but I think Noel has done more investigation than I have.  So if
> others have more info, please chime in.
>
>  As Warner points out the oldest code base we have is Fifth Edition.
> I'm not sure if the KS11 code is still there.  I did not think so.  I
> thought it ran on 11/40 and 11/45.
>
> The V1 work was for a PDP-7 and is before the first 11/20 was secured.
> The point is that I think there is a hole in the the SW we have.
>

V0 was for the pdp-7/pdp-9. V1 was the first port to the 11/20. V2 still
supports the 11/20, but V3 and V4 move heavily to the 11/40s and 11/45s.

We have printouts for V0. And the kernel for V1 with bits and pieces in the
V2 to V3 timeframe that folded into the Unix-Jun72 efforts.

Warner


> As for RK03 vs. RK05  -- *I think I can help a little*.  RK02/RK03 used
> an RK-11C.  I'm fairly sure that the RK05,  used the RK11-D controller.
>  The '72 peripherals' handbook describes the former and the '76 the later.
> But if you believe the handbook, both supported 203 cylinders and 2.45M
> bytes/disk with 512 byte sectors.  The difference seems to have been in
> drive performance.
>
> On Fri, Sep 17, 2021 at 10:34 AM Warner Losh <imp@bsdimp.com> wrote:
>
>>
>>
>> On Fri, Sep 17, 2021 at 8:10 AM Roland via TUHS <tuhs@minnie.tuhs.org>
>> wrote:
>>
>>> Hello Unix fanatics,
>>>
>>> I have a PDP11/20 and I would love to run an early Unix version on it.
>>> I've been working on the hardware for a while and I'm getting more and more
>>> of the pieces back online again. The configuration will be two RK05 hard
>>> disks, TU56H tape, PC11 paper tape reader/puncher and a RX01 floppy drive.
>>> Unfortunately I don't have a MMU or paging option. But it seems that the
>>> earliest versions of Unix do not need the extra memory.
>>>
>>> Does anyone have RK05 disk images for these early Unix versions? That
>>> would be a great help. Otherwise it would be great to have some input about
>>> how to create a bootable Unix pack for this machine.
>>>
>>
>> V5 is the earliest Unix we have contemporary images from. We have
>> fragments from everything else earlier, including files scavenged/recovered
>> from early DECtapes and some code recovered from kernel listings from a
>> Unix course that was put together by Bell Labs...
>>
>> The Unix 1972 project that some TUHS members did. I think it's in the
>> TUHS distribution archive, but also on github. I think Warren Toomey's repo
>> is the canonical one https://github.com/DoctorWkt/unix-jun72 but
>> https://github.com/c3x04/Unix-1st-Edition-jun72 has a couple of newer
>> fixes for a docker file to contain the simh simulator. I'm unsure what
>> hardware that's supported, though.  The machine file suggests:
>>
>> rk03/rk11   177400     disk             RK
>> dc11        174000     tty?             (not supp?)
>> tc11/tu56   177340     dec tape         DTn (not showing up in simh?)
>> rf11/rs11   177460     fixed head disk  RF
>> kw11-l      177546     clock            CLK
>> pc11        177550     paper tape       PTR/PTP
>> asr-33      177560     tty?             TTI, TTO
>>
>> which has an RK03, not sure how close that is to an RK05, so some tweaks
>> may be needed.
>>
>> Warner
>>
>>
>>> A bit about the hardware restoring is on the vcfed forum:
>>>
>>> https://www.vcfed.org/forum/forum/genres/dec/78961-rk05-disk-drive-versions
>>> https://www.vcfed.org/forum/forum/genres/dec/80723-pdp11-20-restoring
>>>
>>> Booting RT11 from RK05
>>> https://youtu.be/k0tiUcRBPQA
>>> TU56H tape drive back online
>>> https://youtu.be/_ZJK3QP9gRA
>>>
>>> Thanks in advance!
>>> Roland Huisman
>>>
>>>
>>>
>>

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 14:33   ` Warner Losh
  2021-09-17 15:32     ` Clem Cole
@ 2021-09-17 16:05     ` Roland via TUHS
  1 sibling, 0 replies; 17+ messages in thread
From: Roland via TUHS @ 2021-09-17 16:05 UTC (permalink / raw)
  To: tuhs

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Hi Warner,
Thanks for your reply!

V5 is the earliest Unix we have contemporary images from. We have fragments from everything else earlier, including files scavenged/recovered from early DECtapes and some code recovered from kernel listings from a Unix course that was put together by Bell Labs...
What I foundon Wikipedia about Unix V5 is that is needs an MMU. " 5th Edition Targetedthe PDP-11/40 and other 11 models with 18 bit addresses." Because it uses18 bit address space it probably expects 248K of memory. My machine does nothave a paging option or mmu. So I think that means that I can't use V5 unfortunately...


The Unix 1972 project that some TUHS members did. I think it's in the TUHS distribution archive, but also on github. I think Warren Toomey's repo is the canonical one https://github.com/DoctorWkt/unix-jun72 but https://github.com/c3x04/Unix-1st-Edition-jun72 has a couple of newer fixes for a docker file to contain the simh simulator. I'm unsure what hardware that's supported, though.  The machine file suggests:
rk03/rk11   177400     disk             RK
dc11        174000     tty?             (not supp?)
tc11/tu56   177340     dec tape         DTn (not showing up in simh?)
rf11/rs11   177460     fixed head disk  RF
kw11-l      177546     clock            CLK
pc11        177550     paper tape       PTR/PTP
asr-33      177560     tty?             TTI, TTO

which has an RK03, not sure how close that is to an RK05, so some tweaks may be needed.
That RK03 isa Diablo 31. It uses the same packs and same interface as the RK05 and is 100%compatible. The RK05 was build by Digital itself and not by Diablo any more. I have the TC11/TU56, PC11, asr33 tty and KW11-L line clock as well. So that is almost the complete list of devices you showed here...


So if it is possible to generate a RK03/RK05 disk image from that simulator then I think I can put that on a real RK05 disk pack. But I'm completely new in this old Unix era... So if anyone could help to generate such an image then it would be a great help!
Regards, Roland

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 15:32     ` Clem Cole
@ 2021-09-17 16:04       ` Roland via TUHS
  2021-09-17 16:14         ` Clem Cole
  2021-09-17 16:13       ` Warner Losh
  1 sibling, 1 reply; 17+ messages in thread
From: Roland via TUHS @ 2021-09-17 16:04 UTC (permalink / raw)
  To: tuhs

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 Hi Clem,

FYI:  The KS11 MMU for the 11/20 was built by CSS and was not on the product list as it were. To my knowledge, no hardware or prints of it survive.    I've been told it was much more similar to the MMU in the KA10 than the scheme eventually done for the 11/45/55/70 and the 11/40 class systems - but I think Noel has done more investigation than I have.  So if others have more info, please chime in.
There is a KT11B paging option that makes the PDP11/20 a 18 bit machine. It looks a bit like the TC11 DECtape controller. I've got the schematics from the internet. But I have no idea how it compares to the later MMU units from the software perspective.

As Warner points out the oldest code base we have is Fifth Edition.    I'm not sure if the KS11 code is still there.  I did not think so.  I thought it ran on 11/40 and 11/45.
Yes, that is what I found too. V5 expects an 11/40 with at least 18 bits memory address space.

The V1 work was for a PDP-7 and is before the first 11/20 was secured.  The point is that I think there is a hole in the the SW we have.
Too bad, but you never know what is still hidden in some attics...

As for RK03 vs. RK05  -- I think I can help a little.  RK02/RK03 used an RK-11C.  I'm fairly sure that the RK05,  used the RK11-D controller.   The '72 peripherals' handbook describes the former and the '76 the later.  But if you believe the handbook, both supported 203 cylinders and 2.45M bytes/disk with 512 byte sectors.  The difference seems to have been in drive performance.
Yes the RK03 was the Diablo 31 with a DEC label on it. 100% compatible with RK11D and RK05. You can swap the packs between these drives as well... So I'm hoping for a disk image for such a drive... 😊

Regards, Roland
  

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* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
@ 2021-09-17 15:35 Noel Chiappa
  2021-09-17 18:28 ` Phil Budne
  0 siblings, 1 reply; 17+ messages in thread
From: Noel Chiappa @ 2021-09-17 15:35 UTC (permalink / raw)
  To: tuhs; +Cc: jnc

    > From: Roland Huisman

    > I have a PDP11/20 and I would love to run an early Unix version on
    > it. ... But it seems that the earliest versions of Unix do not need the
    > extra memory.  Does anyone have RK05 disk images for these early Unix
    > versions?

Although the _kernel_ source for V1 is available:

  https://minnie.tuhs.org//cgi-bin/utree.pl?file=V1

most of the rest is missing; only 'init' and 'sh' are available. So one would
have to write almost _everything_ else. Some commands are available in PDP-11
assembler in later versions, and might be movable without _too_ much work -
but one would have to start with the assembler itself, which is luckily in
assembler.


If I were trying to run 'UNIX' on an -11/20, I think the only reasonable
choice would be MINI-UNIX:

  https://gunkies.org/wiki/MINI-UNIX

It's basically V6 UNIX with all use of the PDP-11 memory management
removed. The advantage of going MINI-UNIX is that almost all V6 source
(applications, drivers, etc) will run on it 'as is'.

It does need ~56KB of main memory. If you don't have that much on the -11/20,
LSX (links in the above) would be an option; it's very similar to MINI-UNIX,
but is trimmed down some, to allow its use on systems with less main memory.

I'm not sure if MINI-UNIX has been run on the -11/20, but it _should_ run
there; it runs on the -11/05, and the only differences between the /20 and the
/05 are that the /20 does not have the RTT instruction (and I just checked,
and MINI-UNIX doesn't use RTT), and SWAB doesn't clear the V condition code
bit. (There are other minor differences, such as OP Rn, (Rn)+ are different on
the -11/20, but that shouldn't be an issue.)

Step 1 would be to get MINI-UNIX running on an -11/20 under a simulator; links
in the above to get you there.

	Noel

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 14:33   ` Warner Losh
@ 2021-09-17 15:32     ` Clem Cole
  2021-09-17 16:04       ` Roland via TUHS
  2021-09-17 16:13       ` Warner Losh
  2021-09-17 16:05     ` Roland via TUHS
  1 sibling, 2 replies; 17+ messages in thread
From: Clem Cole @ 2021-09-17 15:32 UTC (permalink / raw)
  To: Warner Losh; +Cc: tuhs

[-- Attachment #1: Type: text/plain, Size: 3516 bytes --]

FYI:  The KS11 MMU for the 11/20 was built by CSS and was not on the
product list as it were. To my knowledge, no hardware or prints of it
survive.    I've been told it was much more similar to the MMU in the KA10
than the scheme eventually done for the 11/45/55/70 and the 11/40 class
systems - but I think Noel has done more investigation than I have.  So if
others have more info, please chime in.

 As Warner points out the oldest code base we have is Fifth Edition.    I'm
not sure if the KS11 code is still there.  I did not think so.  I thought
it ran on 11/40 and 11/45.

The V1 work was for a PDP-7 and is before the first 11/20 was secured.  The
point is that I think there is a hole in the the SW we have.

As for RK03 vs. RK05  -- *I think I can help a little*.  RK02/RK03 used an
RK-11C.  I'm fairly sure that the RK05,  used the RK11-D controller.   The
'72 peripherals' handbook describes the former and the '76 the later.  But
if you believe the handbook, both supported 203 cylinders and 2.45M
bytes/disk with 512 byte sectors.  The difference seems to have been in
drive performance.

On Fri, Sep 17, 2021 at 10:34 AM Warner Losh <imp@bsdimp.com> wrote:

>
>
> On Fri, Sep 17, 2021 at 8:10 AM Roland via TUHS <tuhs@minnie.tuhs.org>
> wrote:
>
>> Hello Unix fanatics,
>>
>> I have a PDP11/20 and I would love to run an early Unix version on it.
>> I've been working on the hardware for a while and I'm getting more and more
>> of the pieces back online again. The configuration will be two RK05 hard
>> disks, TU56H tape, PC11 paper tape reader/puncher and a RX01 floppy drive.
>> Unfortunately I don't have a MMU or paging option. But it seems that the
>> earliest versions of Unix do not need the extra memory.
>>
>> Does anyone have RK05 disk images for these early Unix versions? That
>> would be a great help. Otherwise it would be great to have some input about
>> how to create a bootable Unix pack for this machine.
>>
>
> V5 is the earliest Unix we have contemporary images from. We have
> fragments from everything else earlier, including files scavenged/recovered
> from early DECtapes and some code recovered from kernel listings from a
> Unix course that was put together by Bell Labs...
>
> The Unix 1972 project that some TUHS members did. I think it's in the TUHS
> distribution archive, but also on github. I think Warren Toomey's repo is
> the canonical one https://github.com/DoctorWkt/unix-jun72 but
> https://github.com/c3x04/Unix-1st-Edition-jun72 has a couple of newer
> fixes for a docker file to contain the simh simulator. I'm unsure what
> hardware that's supported, though.  The machine file suggests:
>
> rk03/rk11   177400     disk             RK
> dc11        174000     tty?             (not supp?)
> tc11/tu56   177340     dec tape         DTn (not showing up in simh?)
> rf11/rs11   177460     fixed head disk  RF
> kw11-l      177546     clock            CLK
> pc11        177550     paper tape       PTR/PTP
> asr-33      177560     tty?             TTI, TTO
>
> which has an RK03, not sure how close that is to an RK05, so some tweaks
> may be needed.
>
> Warner
>
>
>> A bit about the hardware restoring is on the vcfed forum:
>>
>> https://www.vcfed.org/forum/forum/genres/dec/78961-rk05-disk-drive-versions
>> https://www.vcfed.org/forum/forum/genres/dec/80723-pdp11-20-restoring
>>
>> Booting RT11 from RK05
>> https://youtu.be/k0tiUcRBPQA
>> TU56H tape drive back online
>> https://youtu.be/_ZJK3QP9gRA
>>
>> Thanks in advance!
>> Roland Huisman
>>
>>
>>
>

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^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option
  2021-09-17 14:09 ` Roland via TUHS
@ 2021-09-17 14:33   ` Warner Losh
  2021-09-17 15:32     ` Clem Cole
  2021-09-17 16:05     ` Roland via TUHS
  0 siblings, 2 replies; 17+ messages in thread
From: Warner Losh @ 2021-09-17 14:33 UTC (permalink / raw)
  To: Roland; +Cc: tuhs

[-- Attachment #1: Type: text/plain, Size: 2255 bytes --]

On Fri, Sep 17, 2021 at 8:10 AM Roland via TUHS <tuhs@minnie.tuhs.org>
wrote:

> Hello Unix fanatics,
>
> I have a PDP11/20 and I would love to run an early Unix version on it.
> I've been working on the hardware for a while and I'm getting more and more
> of the pieces back online again. The configuration will be two RK05 hard
> disks, TU56H tape, PC11 paper tape reader/puncher and a RX01 floppy drive.
> Unfortunately I don't have a MMU or paging option. But it seems that the
> earliest versions of Unix do not need the extra memory.
>
> Does anyone have RK05 disk images for these early Unix versions? That
> would be a great help. Otherwise it would be great to have some input about
> how to create a bootable Unix pack for this machine.
>

V5 is the earliest Unix we have contemporary images from. We have fragments
from everything else earlier, including files scavenged/recovered from
early DECtapes and some code recovered from kernel listings from a Unix
course that was put together by Bell Labs...

The Unix 1972 project that some TUHS members did. I think it's in the TUHS
distribution archive, but also on github. I think Warren Toomey's repo is
the canonical one https://github.com/DoctorWkt/unix-jun72 but
https://github.com/c3x04/Unix-1st-Edition-jun72 has a couple of newer fixes
for a docker file to contain the simh simulator. I'm unsure what hardware
that's supported, though.  The machine file suggests:

rk03/rk11   177400     disk             RK
dc11        174000     tty?             (not supp?)
tc11/tu56   177340     dec tape         DTn (not showing up in simh?)
rf11/rs11   177460     fixed head disk  RF
kw11-l      177546     clock            CLK
pc11        177550     paper tape       PTR/PTP
asr-33      177560     tty?             TTI, TTO

which has an RK03, not sure how close that is to an RK05, so some tweaks
may be needed.

Warner


> A bit about the hardware restoring is on the vcfed forum:
> https://www.vcfed.org/forum/forum/genres/dec/78961-rk05-disk-drive-versions
> https://www.vcfed.org/forum/forum/genres/dec/80723-pdp11-20-restoring
>
> Booting RT11 from RK05
> https://youtu.be/k0tiUcRBPQA
> TU56H tape drive back online
> https://youtu.be/_ZJK3QP9gRA
>
> Thanks in advance!
> Roland Huisman
>
>
>

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^ permalink raw reply	[flat|nested] 17+ messages in thread

* [TUHS] Unix for PDP11/20 w/o mmu or paging option
       [not found] <2007825471.713023.1631887763341.ref@mail.yahoo.com>
@ 2021-09-17 14:09 ` Roland via TUHS
  2021-09-17 14:33   ` Warner Losh
  0 siblings, 1 reply; 17+ messages in thread
From: Roland via TUHS @ 2021-09-17 14:09 UTC (permalink / raw)
  To: tuhs

[-- Attachment #1: Type: text/plain, Size: 1000 bytes --]

Hello Unix fanatics,
I have a PDP11/20 and I would love to run an early Unix version on it. I've been working on the hardware for a while and I'm getting more and more of the pieces back online again. The configuration will be two RK05 hard disks, TU56H tape, PC11 paper tape reader/puncher and a RX01 floppy drive. Unfortunately I don't have a MMU or paging option. But it seems that the earliest versions of Unix do not need the extra memory.
Does anyone have RK05 disk images for these early Unix versions? That would be a great help. Otherwise it would be great to have some input about how to create a bootable Unix pack for this machine.

A bit about the hardware restoring is on the vcfed forum:https://www.vcfed.org/forum/forum/genres/dec/78961-rk05-disk-drive-versionshttps://www.vcfed.org/forum/forum/genres/dec/80723-pdp11-20-restoring
Booting RT11 from RK05https://youtu.be/k0tiUcRBPQATU56H tape drive back onlinehttps://youtu.be/_ZJK3QP9gRA
Thanks in advance!Roland Huisman

 

[-- Attachment #2: Type: text/html, Size: 2311 bytes --]

^ permalink raw reply	[flat|nested] 17+ messages in thread

end of thread, other threads:[~2021-09-17 21:22 UTC | newest]

Thread overview: 17+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-09-17 20:18 [TUHS] Unix for PDP11/20 w/o mmu or paging option Noel Chiappa
2021-09-17 20:47 ` Clem Cole
  -- strict thread matches above, loose matches on Subject: below --
2021-09-17 15:35 Noel Chiappa
2021-09-17 18:28 ` Phil Budne
2021-09-17 19:43   ` Clem Cole
2021-09-17 19:51     ` Brantley Coile
2021-09-17 20:07       ` Clem Cole
2021-09-17 21:21       ` Phil Budne
     [not found] <2007825471.713023.1631887763341.ref@mail.yahoo.com>
2021-09-17 14:09 ` Roland via TUHS
2021-09-17 14:33   ` Warner Losh
2021-09-17 15:32     ` Clem Cole
2021-09-17 16:04       ` Roland via TUHS
2021-09-17 16:14         ` Clem Cole
2021-09-17 16:44           ` Roland via TUHS
2021-09-17 16:13       ` Warner Losh
2021-09-17 16:17         ` Clem Cole
2021-09-17 16:05     ` Roland via TUHS

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