[Simh] Of DEC and cards

[Timothe Litt]

In the TOPS-10 world, ANF-10 RJE stations could have card readers and
printers.  The TOPS-10/20 DN200 also.

But most "RJE" station software on the DEC side made the foreign
mainframe look like a batch queue, and you would submit a file to that
queue.  The software (typically DEC 2780/3780 emulation for
{TOPS-10,TOPS-20, VMS, ...}) would send the file to the mainframe from
an imaginary card reader; results similarly to an imaginary printer
(ending up in a .log or other file).  I suppose "virtual" would be the
modern word for "imaginary", but it comes to the same thing :-)

On the KL based systems, the software was a combination of PDP-11 front
end code (a dedicated DN20) and code running on the KL.  The KS used a
KDP, though there was also a "DN22" remote station.

I don't know exactly what UNIX did - wasn't in that world much then. 
But I wouldn't be surprised if the strategy was similar - user prepares
a file, software does the code conversions to/from EBCDIC, and the usual
lies told (er, device emulation performed) in both directions...  That
would certainly have led to the emulation work you recall - especially
given the fluid definitions of character sets at the time.  I don't
recall the same efforts to offload development to UNIX as to the DEC
proprietary systems - IIRC, compilers for legacy languages (COBOL, RPG,
PL/I) came to UNIX rather later, and with less rich/performant
implementations. 

In my experience, physical card equipment, as previously noted, was
either a legacy/migration requirement, or simply a bureaucratic legacy
"requirement".  The DEC value proposition was that cards were expensive,
awkward, slow, and painful to create, modify/debug with.  Interactive TS
solved those problems; the emulations were a medium of exchange between
the legacy/enterprise systems and the more productive DEC systems. 

Readers: quite common.  Punches, much less so.

On 13-Feb-20 13:37, Clem Cole wrote:
> One last reply here, but CCing COFF where this thread really belongs...
>
> On Thu, Feb 13, 2020 at 12:34 PM Timothe Litt <litt at ieee.org
> <mailto:litt at ieee.org>> wrote:
>
>     OTOH, and probably more consistent with your experience, card
>     equipment was
>
>     almost unheard of when the DEC HW ran Unix...
>
> You're probably right about that Tim, but DEC world was mostly
> TOPS/TENEX/ITS and UNIX.  But you would think that since a huge usage
> of UNIX systems were as RJE for IBM gear at AT&T.  In fact, that was
> one of the 'justifications' if PWB.  I'm thinking of the machine rooms
> I saw in MH, WH and IH, much less DEC, Tektronix or my
> universitytime.  It's funny, I do remember a lot of work to emulate
> card images and arguments between the proper character set
> conversions, but  I just don't remember seeing actual card readers or
> punches on the PDP-11s, only on the IBM, Univac and CDC systems. 
>
> As other people have pointed out, I'm sure they must have been around,
> but my world did not have them.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.trailing-edge.com/pipermail/simh/attachments/20200213/0a040d26/attachment-0001.html>