"A Turist's Guide to ITS"

A nice in-person adventure from @oscarv - you can download and run the Incompatible Timesharing System and do all the same things, from chess to C to job control and networking. And emacs, of course. And the DDT debugger.

“The local spelling “TURIST” is an artifact of six-character filename limitations, which is traceable to six SIXBIT encoded characters …”

I’m just going to quote a bit - a big bit - about the simulated hardware in play here, being the Interlude:

Interlude: the simulated hardware (KA10 version)

By now, it will help to have an overview of the tons of hardware you are sitting on. You can see the configuration in the file its/build/pdp10-ka/run. I’m just describing what is in there.

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The KA10 PDP-10 (the main system running ITS) and the connected PDP-11/20

A PDP-10 KA10, with:

• four RP03 drives, 41MB each and 1024K words of memory
• deCoriolis clock (pd)
• a 340 pixel display (dpy) and a Stanford keyboard used with it (stk)
• ? (dk)
• Datapoint Kludge, for virtual Datapoint terminals (dpk device, port 10002)
• Morton Box terminals (mty)
• IMP (Interface Message Processor): the interface to the internet (imp)
• paper tape reader (ptr) to boot the KA10 into DSKDMP, using dskdmp.rim tape
• magtape (mta) and DECtape units (dt)

The Knight TV system – homebrew user terminals controlled by the PDP-11/20. Developed in-house at MIT. See https://github.com/PDP-10/its/wiki/Knight-TV-and-keyboard and http://pdp-6.net/knight-tv/knight-tv.html

MIT-AI had a thing called the Knight TV terminal system, which was one of the first (maybe the first) bit-mapped display systems; it had a PDP-11/05 (the TV11) with a bunch of bit-mapped memory buffers on it, attached to the KA10 through a thing called the Rubin 10-11 interface, which was a memory window. There were N terminal display buffers, and a video switch, and a whole bunch of CRT/keyboard sets scattered around the 8th/9th/etc floors of 545 Tech Square, attached to the video switch. The first N people got to use a buffer, otherwise you had to wait for one to free up.

  • Knight TV terminals (tk device, normally simulated as telnet port 10000)
  • Rubin PDP-10 to PDP-11 interface (ten11)

The KA10 is also linked (implemented as separate simulators) to:
• a PDP-6 (auxcpu device) which comes with its own 340 display; and a front panel you need to operate;
• a GT 40 (basically a PDP-11/05 with pixel display, which could be used a terminal).

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The PDP6 and the GT40 (a PDP-11/05 with graphics display)

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