I remember when U Wisconsin ECE got their PDP-11/20 and I saw DOS FORTRAN get stuck for the very first time. I told the more senior student who was responsible for getting things going, preparing documentation, etc. that the machine was in a loop, and never coming out. He laughed at me, claiming there was no way I could know that. Bzzzzzt. Wrong. Tee Hee. That machine is now in my personal collection.
(PDP-11 DOS tended to scramble file system links and get stuck like that - which inevitably required reloading the operating system disk - an RC11 that still ran just fine when I last spun it up a year or so ago). On 7/15/2015 12:35 PM, Paul Koning wrote: > >> It wasn't _just_ eye candy; it was a real help in problem debugging (when the >> machine was stopped), and you could tell a lot about what the machine was >> doing (when it was running) from the way the lights changed. > > Absolutely. When DEC introduced the Remote Diagnostic Console for the 11/70, > they started deploying those internally. That makes sense. But in the > RSTS/E development group, we put our foot down and told them “take it out and > give back our blinkenlights” because for OS development the ability to judge > what the machine is doing, or spot strange behavior, from the light patterns > is quite important. > ... > paul >
