26 Feb
2020
26 Feb
'20
11:49 p.m.
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.
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.
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.
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.
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.
On 2/26/20 4:01 PM, Ray Jewhurst wrote:
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.
Ray
On Wed, Feb 26, 2020, 3:44 PM Robert Armstrong <bob at jfcl.com
<mailto:bob at jfcl.com>> wrote:
Thomas DeBellis [tommytimesharing at gmail.com
<mailto:tommytimesharing at gmail.com>] wrote:
Otherwise, personally, I think it would be a cool
idea for SIMH
to have
full support for DTE's ...
? 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.
? 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.
? It runs TOPS10 fairly well, though.
Bob