[pdp7-unix] Testing ttt

Phil Budne phil at ultimate.com
Thu Oct 24 06:13:42 AEST 2019

It looks to me like the start of ttt1.s checks the argument list
(perhaps the program name) for the letters "dt" to decide whether
or not to use the display:

   lac 017777
   tad d1
   dac 9f+t
   lac 9f+t i
   sad qdt
   jmp loop


qdt: <dt>

So try linking or renaming the binary.

Figuring how the programs work, and whether or not they've been
entered correctly is probably than writing display simulation code!

I had it easy for the PDP-1 Type 30, PDP-6 Type 340 and VT11 for PDP-1
& PDP-6 spacewar, and PDP-11 lunar lander display programs: the code
had either come to me via digital media, or had been tested on other
simulators first!

But I've also suffered thru finding typos in PDP-1 ddt & macro, the
UNIX-7 kernel and many of the utilities (including as, sh, roff, ed,
and db).

This is HARD WORK (tho having multiple type-ins of the code is usually
a big help, it's not a quarantee that multiple people won't interpret
the same smudges the same way).  You'll get greater sympathy from me
if you say "Can someone help me figure out...." as opposed to saying
or implying "it must be broken" (as you did earlier with the cas

This is a work in progress, and you're trying to put icing on a cake
that hasn't finished baking.  I can't even tell you if the display
code paths in the system (including the capture system call) are correct!


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