On 12/16/2015 7:57 AM, Paul Koning wrote:
On Dec 15, 2015, at 10:10 PM, Chuck Guzis <[email protected]> wrote:
On 12/15/2015 01:48 PM, Dave Wade wrote:
What I meant was are they still on 9-track, or some kind of
tape-in-a-file disk? IBM tapes are usually written to AWS format
files not the formats (.TAP ?) used by SIMH... Some source to extract
some versions of these from AWS files (and windows executables) are
in this ZIP file:-
Came right off a 1600 cpi tape, identified as a CMS dumpfile.
What really strikes me as odd, is that ANSI/IBM tape labels were pretty much
the standard rule of thumb then; why the heck did IBM invent something new and
obscure?
IBM standard labels are older than ANSI. Then again, IBM (in OS/360 at least) had something they
called "ANSI label" that were not actually ANSI at all. They used "8 bit
ASCII" which was a bizarre code created from standard 7 bit ASCII by moving one or two of the
bits (bit 6 to bit 7? I don't remember).
On the Microdata 1621 system we had it was 4 assembler instructions in
a loop to convert a string from Ascii to Ebcdic using that weird ascii code.
I use a table now when I code in C to convert from that ASCII to what we
call ascii. I call it high bit on ascii, but it isn't precisely that.
I have an entire OS that uses that, and I ran across it back in the 70's
on a few other minis, but the ANSI version supplanted it early on.
FWIW referring to the Jay West 1600's from University of Missouri, Rolla
thanks
Jim
paul
