[HECnet] A2RTR downtime

Tue Oct 19 13:28:41 PDT 2021

I'm only familiar with the source code for KLH10 to any great extent and 
a small subset of the code for SIMH (the 340).  KLH10 implements KL10 
and KS10 Tops-20 and ITS paging microcode.  I thought I remembered some 
stubs for the KI, but I wouldn't swear to it.

I believe the KA10 was de-supported as of the 6.00 series monitor. WPI 
had 6.05 running on our KA10, but it was "much modified" as we had some 
real hackers on staff (I wasn't one of them as I worked in Marlboro)

The KI had to have been de-supported by 7.04 because the October 1988 
version of the Tops-10 Monitor Calls Reference Manual has a section on 
user mode extended addressing (2.2).

The SMP code at one point did run on a KI as this is what it was 
debugged on.  I'm pretty sure I remember seeing two KI's in the same 
machine room as 2102, 2116, 2136 and 2137, but I could be wrong.  I 
don't remember their processor numbers.  Marlboro employees would go 
starry eyed talking about SMP...

It is tempting to speculate that it might not be an extremely heavy lift 
to do KI paging as it is a subset of TENEX paging (which the KL 
implements a subset of).  What I mean is that you would chuck more code 
than you'd write.  I could, of course, be completely delusional.  I 
would think that probably SIMH would be your best bet in that arena.

The only patch I'm aware of for NOV 2021 T10 DECnet is what I came up 
with.  I've reached out to some people off list to socialize this.
> ------------------------------------------------------------------------
> On 10/18/21 7:13 PM, Peter Lothberg wrote:
>
> This is kind of a bit off topic.. But...
>
> So I have a lot of T10 7.02 based code for KI10 (using tops10 KI 
> paging...). None of the PDP10 emulators do T10 KI paging..
>
> 7.03 has lots of internal changes that did not work on KI, so back 
> ported  DECnet 4 etc from 7.03 to 7.02 (remember we had KI CPU's..)
>
> Was there 7.02 that used KL10/Tops20 paging? I don't have the dist 
> tapes any longer?
>
> Or is there a PDP10 emulator that do KI Tops10 paging that would run 
> my 7.02?
>
> --P
>
> So what's the actual T20 patch for NOV 2021 DECnet?
>
> Ps, tops10 does not  "cross compile" between versions well (or at all..)
> ------------------------------------------------------------------------
>
>     *From: *"tommytimesharing" <tommytimesharing at gmail.com>
>     *To: *"hecnet" <hecnet at Update.UU.SE>
>     *Sent: *Monday, October 18, 2021 3:00:00 PM
>     *Subject: *Re: [HECnet] A2RTR downtime
>
>     I wouldn't worry about it; I don't use VENTI all that much,
>     either.  …/Except/ when I do…  Then I have to tell you that it has
>     proven to be positively invaluable and I am very grateful for that!
>
>     If this were critical, then I'd think about getting off my butt
>     and putting up Tops-10 somewhere on one of my home systems.  But
>     that would blow a lot of time; I haven't done a MONGEN since…well,
>     I honestly can't remember—it's well over four decades and I never
>     knew that part of it well to begin with.    Come to think of it, I
>     might have been doing a ONCE and not a MONGEN.
>
>     Actually, having a guest account on other HECnet systems has also
>     proved invaluable for chasing down arcane Tops-20 issues.  Thanks
>     all!!
>
>     I reached out to Lars Brinkhoff concerning my Tops-10 patch and he
>     said he would distribute wherever it made "sense" to do so.  If I
>     get any feedback, I will forward it.  Otherwise, let me know if
>     there is any way I can provide assistance.
>
>     Yes, it is a shame about the STOPCODE, but it would appear that
>     the maintainer had some different ideas in the mid-1980's when
>     this code was put in about what the usage of Tops-10 would be. 
>     This comment is illustrative, the first sentence being key:
>
>         _I doubt very much that the date itself has really gone past
>         2021_.  Probably someone smashed an AC or the routine to get
>         the time from the monitor is returning junk. However, on
>         November 9, 2021, it appears that many people will see this
>         problem so prepare your SPR for that date.
>
>     I think the problem is that Tops-10 didn't have the kind of
>     die-hard fanatics supporting it (read, MRC) that Tops-10 did, so
>     stuff like this was caught and fixed years ago.  D36COM has an
>     edit date of 2001 for this, but since it is from Gorin, it's
>     probably older.
>
>     I continue to find Y2K things to clean up, these days mostly in
>     the listings from various compilers and the remaining CUSP's that
>     MRC didn't catch.
>
>     Another thing I fix are internal time of day comparisons.  This is
>     stored as an unsigned 36 bit fixed fraction having resolution to
>     about ⅓ of a second, 35 bits bringing you to 27-Sep-2217 20:00:00
>     EST US, the full 36 taking you to 7-Aug-2576 19:59:59 EST US. 
>     Since the PDP-10 only has signed comparisons, all single
>     comparison arithmetic will break in a mere 195 years.  Fixing that
>     double word signed compares has given me some more breathing
>     room.  In 554 years, I'm sure I'll have thought of something else…
>
>         ****
>
>         ------------------------------------------------------------------------
>
>         On 10/18/21 11:19 AM, Robert Armstrong wrote:
>
>         ***
>
>             *Second* is VENTI; I had wanted to test something on it
>             and it doesn't appear to be online.
>
>         *
>
>           Sorry, I’m somewhat lazy about booting it up when the host
>         system is rebooted.  I don’t use VENTI that much.
>
>         **
>
>             Had you had any interest in trying it?
>
>           It sounds like I’m going to have to.  It’s a shame this
>         STOPCODE was a halt and not just a debug one; at least the
>         latter would have allowed the system to continue running.
>
>           This also means I have to re-discover how to do a MONGEN and
>         build.  There was a time, 30 years ago (actually, 40 years
>         ago) when I could have done it from memory but now I’ll have
>         to read the manual again
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sonic.net/pipermail/hecnet-list/attachments/20211019/f31b47da/attachment-0001.htm>