Remote job submission from PDP-11

Ethan Dicks ethan.dicks at
Wed Oct 7 10:00:41 CDT 2020

On Wed, Oct 7, 2020 at 10:20 AM Paul Koning via cctalk
<cctalk at> wrote:
> >> On Wed, Oct 7, 2020 at 5:07 AM Peter Allan via cctalk
> >> <cctalk at> wrote:
> >>> I am looking for the following software products for a PDP-11, ideally to
> >>> be run on RSX-11M.
> >>>
> >>> RJE/HASP
> >>> 2780/3780 Protocol Emulator

> > Hercules does have 2703 emulation, and bisync emulation does seem to be
> > present in SimH.  I think both support some level of TCP, so you might
> > be able to lash them up that way - but I would expect some hiccups along
> > the way.  But that would indeed still leave the software question from
> > the original post.

I found this looking for info on Hercules and 2703 emulation...

> I would think that the simulators have very little to do here, at least on the PDP11 end.  If a sync serial device is emulated as a stream of bytes, the rest is up to the software.

Yes.  The CPU simulation on the PDP-11 side has nothing special to do,
but I don't see that there is device emulation for DU11 or DV11 sync
serial cards, and the application code running on the PDP-11 side is
going to want to see those device registers.  The transport layer is
immaterial, of course.

> At least in the 2780 emulation case, where BISYNC protocol handling is in software and the serial ports just are raw byte pipes.

Yes, Bisync is just a stream of raw bytes, but ISTR the COM5025 (the
common 1970s USART for this purpose) might throw in flag bytes or
something minor that the application doesn't know about or see, but
the other end sees in the received byte stream.  It's been a few
decades since I've scoped a line, and I'd have to pull our code to see
what we fed to the COM5025 on the COMBOARD.

> Then it's a matter of finding RJ2780 software.  I know it exists for RSTS, though I've never used it.  (It uses the KG11 to accelerate CRC processing, I'm not sure if that's optional or required.)  RJ2780 was a product family available with a number of operating systems so I'd assume RSTS isn't the only OS that had it.  Finding a copy might be an interesting exercise -- that appears to be the road block Peter is talking about.
>         paul

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