[Simh] EXT :Re: PDP-10 simulation: DEUNA support help needed

[Cory Smelosky]

On Wed, 29 Apr 2015, Rich Alderson wrote:

>
> I suppose you're thinking of the Data Disc terminals, which connected to the
> system through a giant disk (a Librascope, if I have my facts straight).  The
> system wrote on the disk, the terminal displayed that content, keyboard wrote
> on the disk, system acted on the input.
>

Yeah, that's what I was thinking of - thanks.

> These were the terminals which gave the Space Cadet keyboard on the MIT LispMs
> their bucky bits[1] and TeX many of its interesting characters in the low ASCII
> range ("ASCII control characters").

Neat.

>
>> Huh.  Was the VAX one similar?
>
> Further deponent sayeth not.[2]
>

Ahh.

>
> You would still have to assemble a file system by hand.  WAITS originated
> before DEC's Level D disk code, and the systems programmers defined their own
> file system.  PPNs are SIXBIT, so [1,2] is octal 21,,22 in the MFD entry (yes,
> they're right justified in the halfwords).  The last version of the file
> system, which lived on 3 RP07 disks, allocated things in blocks of 9 sectors,
> giving 1K of data + 200 words of "retrieval data" per block (repeated through
> every block of a file).
>

Interesting!

Similar to TOPS-10's FS with multi-unit structures or with some sort of 
striping/parity?

> The issue is that only 3 systems ran WAITS: SU-AI at SAIL, a KL-10 system
> attached to the S-1 project at Lawrence Livermore Labs, and a Foonly F2 at
> CCRMA (the Center for Computer Research in Music and Acoustics, at Stanford).
> Because of the way the system grew, there was never a need for a utility that
> would build a file system from scratch on an initialized disk (like CHECKD in
> TOPS-20 or the ONCE code in Tops-10, or even NSALV in ITS), so no one ever
> wrote one.  The closest thing to it was a program written to move from a
> damaged file system to a new set of RP07s, which relied on working copies of
> several programs on the undamaged disks.
>

I take it from your understanding of the FS you have a utility to do just 
that written? ;)

> Getting a file system working was about 6 months of last year.
>

Thankfully the CIS one seems to be simpler.  It's a bit odd, but seems 
mostly TOPS-10.

> 2065.  It's in an orange corporate cabinet, and started life running TOPS-20.
> We use it for Tops-10 (v7.04) because we have another platform for TOPS-20, one
> on which it has all the memory it really needs.
>

Ah, right.  I recall reading a message you wrote about -20 being starved 
for memory on a 2065.

>
> Hmm.  I have to dig my personal tapes out of a storage locker.
>

Hope you have better luck reading them than I have with trying to make a 
CIS tape. ;)

>
> I assume that's what you listed in a later message.
>

Yeah.  If you need anything specific from it, let me know - I extracted it 
and then recompressed as a UNIX tarball...albeit losing the versioning in 
the process.

>
> Me, too.  TENEX requires either a KA-10 based system with a BBN pager attached,
> or a KI-10 based system (and DEC would sell you a license for their modified
> version).  If I ever have time, I might try getting TENEX to run on our 1070.
>

Does that mean you have bootable TENEX installation media, or would you 
need to construct manually and cross-assemble before rebuilding itself?

>
> Originals, of course.  The Toad-1 System was introduced in 1995.  Cisco was
> founded in 1984, with a business plan that called for building the Toad--all
> the networking stuff was intended by the founders as a cash cow to fund the
> development.
>

Ahh, right.

Interesting.

>> Also: for the LCM SC-40s: The SCSI controller chip can do either HVD or
>> SE, from what I've been told and from my own invstigations...it can be
>> changed by swapping a small daughterboard which doesn't seem to be more
>> than some resistor packs and some line drivers.  Could more easily use
>> say, SCSI2SD on those, that way.
>
> Thanks, Cory!  I'll file that away.
>

Thanks to a commentor on my video the chips are:
75ALS170 Triple Differential Bus Transceiver
75ALS171 Triple Differential Bus Transceiver

so it should be relatively trivial to make your own SE adapters...or take 
some HVD drives from my source...I surely don't need 400!

If you're all too busy there, I could always image the drives if needed. 
I have an operational SCSI imaging box and a quick-and-dirty utility to read 
the volume label and determine if it has an SSL definition (the utility 
doesn't do that - I manually mount in a TOPS-10 install)

>                                                                Rich
>
> [1] Interesting story about the name, recounted in John Markoff's book _What
>    the Dormouse Said_.
>

Thanks!

> [2] I honestly don't know.
>

Seems nobody does :(

-- 
Cory Smelosky
http://gewt.net Personal stuff
http://gimme-sympathy.org Projects