[Simh] Graphics Terminals and Graphic System Phototypesetters

[Paul Koning]

> On Dec 10, 2015, at 10:50 AM, Quentin North <quentin at quentin.org.uk> wrote:
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> 
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>>> On Dec 9, 2015, at 10:33 PM, Will Senn <will.senn at gmail.com> wrote:
>>> ...
>>> Is is possible to simulate a graphics terminal in SimH for the PDP-11/40/45/70. So far, I have been able to get a text console working (I think it's a Teletype ASR-33) and serial consoles (DCI). I have seen some video of real PDP's playing lunar lander and such on graphics terminals, and if this is possible in a simulated environment, I would like to try it out.
>> 
> 
> A common graphics standard for serial terminals was Tektronix and an emulation of a tektronix terminal is available in xterm ...

That's a common one, yes.  But there were plenty of other formats as well, each proprietary to a specific vendor.  Tek was just more successful in making their particular codes into an industry standard.  

There's another angle I didn't mention, not as likely for most of us: you might have a terminal that uses a standard interface but an unexpected communication protocol.  An example would be the Harris 2200 display advertising layout terminal, which uses (I am *not* kidding) bisync in half duplex multipoint mode, over an async serial line (such as a DL11-E) with modem control.  So you could almost do that with SIMH (give or take the modem control) but you'd end up having to implement both the data comm protocol as well as the graphics primitives at the other end of that serial data stream.

	paul