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<p>Not much, regretfully. Tops-20 was first brought up on a KI
processor as a port from BBN TENEX which used a considerably more
sophisticated page box. I don't believe it was ever productized
and these sources are believed lost.</p>
<p>By and large, a KI used some different hardware than a KL (the
RH20 comes to mind) although they could and did share a great deal
of equipment.</p>
<p>You would likely have never seen a DTE on a KS processor; there
was no need and no PDP-11 processor. The KS addressed the Unibus
directly. A DTE was found on PDP-11's (I think 11/34's and
11/40's) to connect them to KL-10's. One side was unibus based
and the other connected to the KL (I don't recall whether it was
massbus based). You could have theoretically used a DTE to
connect a KS to a KL, but I don't believe this was ever done.<br>
</p>
<p>One assumes that SIMH could emulate the unibus side of the DTE
interface for the PDP-11, perhaps encapsulating the packets and
sending them to a KLH10 based DTE via IP datagrams. You could
bring up a nice bit of software, IBM HASP multileaving comes to
mind and perhaps an AN20.</p>
<p>Although he really loved it, MRC had a lot of comments about the
KL. It is a difficult beast to emulate; the page box is far more
complex than the KI (although by no means as complex as the BBN
page box). There are meters and a bunch of other things. The
KL-B class extended addressing complicates things too.<br>
</p>
<div class="moz-cite-prefix">On 2/26/20 4:01 PM, Ray Jewhurst wrote:<br>
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<div>KL simulation for Simh is on its way by Rich Cornwall and
at last check it's only a few months out. He already has a KI
simulator but I am not sure what that will do as far as
TOPS20.</div>
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<div dir="auto">Ray<br>
<br>
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<div dir="ltr" class="gmail_attr">On Wed, Feb 26, 2020, 3:44
PM Robert Armstrong <<a href="mailto:bob@jfcl.com"
moz-do-not-send="true">bob@jfcl.com</a>> wrote:<br>
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<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">>
Thomas DeBellis [<a
href="mailto:tommytimesharing@gmail.com" target="_blank"
rel="noreferrer" moz-do-not-send="true">tommytimesharing@gmail.com</a>]
wrote:<br>
>Otherwise, personally, I think it would be a cool idea
for SIMH to have <br>
>full support for DTE's ...<br>
<br>
That's the problem - the KS never had DTEs, not even
close, and simh only emulates a KS10. The only way out is
to emulate a KL, and that's a big job. KLH10 already does
that pretty well, and I don't think simh will ever acquire
KL emulation.<br>
<br>
The other issue with the KS was that it was limited to
two sections (512KW) of memory, and that's pretty much a
show stopper for all later versions of TOPS20.<br>
<br>
It runs TOPS10 fairly well, though.<br>
<br>
Bob<br>
<br>
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