24 May
2014
24 May
'14
11:12 a.m.
The username field in the archive is of the form used on CDC Cyber computers running NOS
or KRONOS.
University of Illinois was big on CDC machines.
I bet it is some kind of archive format used on CDC machines to create tapes that could be
interchanged with other types of systems, e.g. IBM.
I wish I could remember more detail from my Cyber operator days, as I do vaguely remember
that there was a utility that we ran to create takes in a format that the big IBM
systems on the business side of the company (Tektronix) could read.
Please excuse top posting, my phone won't let me post any other way.
Rick Bensene
-----Original Message-----
From: Chuck Guzis [cclist at sydex.com]
Received: Friday, 23 May 2014, 1:00PM
To: General at bensene.com [General at bensene.com]; Discussion at bensene.com:On-Topic
and Off-Topic Posts [cctalk at classiccmp.org]
Subject: Re: Question about SIMH .TAP files
On 05/23/2014 11:22 AM, Paul Koning wrote:
The 4th word looks like the sort of usernames that
University of
Illinois inflicted on its students (derived from student ID numbers).
Good catch--the tape's from UIUC.
--Chuck
24 May
24 May
11:39 a.m.
On 05/24/2014 11:12 AM, Rick Bensene wrote:
The username field in the archive is of the form used
on CDC Cyber
computers running NOS or KRONOS.
University of Illinois was big on CDC machines.
I bet it is some kind of archive format used on CDC machines to
create tapes that could be interchanged with other types of systems,
e.g. IBM.
I wish I could remember more detail from my Cyber operator days, as I
do vaguely remember that there was a utility that we ran to create
takes in a format that the big IBM systems on the business side of
the company (Tektronix) could read.
WRT the tapes I have, they're long after my time (SCOPE 3.1,6/3.3 era).
KRONOS was still KRONOS and there was talk about renaming SCOPE 3.4
NOS/BE. There was a serious division within the company over which was
better.
There was a SCOPE interchange utility that I vaguely remember. Almost
unmaintained and obscure as heck. Often, it was easier to throw
together some FORTRAN do do the job. I remember doing so when
processing a DECSystem 10 binary tape (5 characters per 36 bit word).
This was pre-6RM. 7600 SCOPE 2 introduced the idea of a common record
management utility, IIRC.
My memories of 6000 tape drivers are mostly from the hated 1LT "long
tape" driver on systems that made extensive use of ECS. It was
entertaining to watch retries, at least.
--Chuck
27 May
27 May
12:10 p.m.
From: Chuck Guzis
Sent: Saturday, May 24, 2014 11:39 AM
On 05/24/2014 11:12 AM, Rick Bensene wrote:
> I wish I could remember more detail from my Cyber
operator days, as I
> do vaguely remember that there was a utility that we ran to create
> takes in a format that the big IBM systems on the business side of
> the company (Tektronix) could read.
There was a SCOPE interchange utility that I vaguely
remember. Almost
unmaintained and obscure as heck. Often, it was easier to throw
together some FORTRAN do do the job. I remember doing so when
processing a DECSystem 10 binary tape (5 characters per 36 bit word).
If it was a binary tape, it was 36 bit words, period. ASCII text is stored as
5 x 7-bit bytes per word.
Or did you mean "5 *8-bit frames* per 36 bit word", for a total of 40 bits?
That was the general standard, called "core-dump format" on PDP-10 operating
systems. Even ASCII text, represented as stated above, ended up in core-dump
format on tape.
Rich
Rich Alderson
Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134
mailto:RichA at LivingComputerMuseum.org
http://www.LivingComputerMuseum.org/
3:14 p.m.
On 05/27/2014 12:10 PM, Rich Alderson wrote:
If it was a binary tape, it was 36 bit words, period.
ASCII text is stored as
5 x 7-bit bytes per word.
Or did you mean "5 *8-bit frames* per 36 bit word", for a total of 40 bits?
That was the general standard, called "core-dump format" on PDP-10 operating
systems. Even ASCII text, represented as stated above, ended up in core-dump
format on tape.
No, nothing at all to do with tape format, unless you count 2 36-bit
words mapping into 9 tape frames. This is the format in which a DEC CE
friend delivered "Adventure" to me. Converting to 6 bit CDC display
code was interesting, particularly since I didn't have any idea of how
the DECSystem 10 stored things. I am relatively certain that the CDC
conversion utility didn't have the vocabulary to unravel it.
Fortunately, it turned out that all I had to do was read two 36 bit
words' worth and translate them into a single 60 bit word, making
provision of the peculiar CDC end-of-line convention.
The game itself posed a few conversion challenges, but it turned into
one of the bigger resource hogs at the time.
--Chuck
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