[Info-vax] What are the earliest DEC operating systems you worked with ?

[Ian Hammond]

On Thursday, March 4, 2021 at 10:36:02 PM UTC+11, Elliott Roper wrote:
> On 3 Mar 2021 at 18:24:22 GMT, "Simon Clubley"
> <clubley at remove_me.eisner.decus.org-Earth.UFP> wrote: 
> 
> > What are the earliest DEC operating systems you worked with ? 
> > 
> > For me, I started with a PDP-11 running RSTS/E V9.{something early}, 
> > then onto VAX/VMS V5.{something} and then onto Alpha VMS V6.{something}. 
> > 
> > I have not touched any Itanium systems. 
> > 
> > Simon.
> PDP-8 TSS-8 
> PDP-11 DOS then everything since except Ultrix. 
> TOPS-10 as a user, about 1975 
> VMS not sure which version, sometime in the early 80's on a 750 
> 
> -- 
> To de-mung my e-mail address:- fsnospam$elliott$$ 
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The PDP-11/20 I worked on might have the been the first to be delivered
to Australia; it was ordered well in advance of the system's release. The 
sales brochures in fact described a different instruction set (the heavily 
bit-encoded architecture).

The PDP-11/20 had 8kw core memory (I think it was 8kw, but it might 
have been 12 or 16), an ASR-33 teletype with paper tape punch and reader
and DECtapes. PTS, the papertape system, was the first I used. Most of my 
time was spent using the switch panel to debug and write binary code. 
The great thing about core memory was that it retained its contents even 
when the system was switched off. I wrote a nano-operating system and
patched IOX (the I/O package) and PTS BASIC so that we could use the 
DECtapes. The PTS system reserved the top 14 words of memory for
a (self-modifying) paper tape bootstrap loader. Some how I managed to 
squeeze a DECtape bootstrap into that space.

We then  purchased two operating systems at the same time: RT-11 
V1.0 and DOSbatch. I booted RT-11 and never got around to looking at 
the other system (because it needed a SYSGEN, I think). I used every
version of RT-11, up until V5.5.

One of the delivered system DECtapes must have been previously used
internally because I found source code past the last file on the tape.

We later doubled the memory bank. At the time I couldn't conceive how 
I could possibly use that seemingly vast new area of additional memory.

My first VAX was a 730 (which we thought of as "almost a VAX"). We 
used it largely as transparent file server and a product development 
machine.