DrG PDP=11's . a friend was working for a company who 's boos kept typing LP instead of LP: He would create files named "LP." instead of printing to the line printer. I went in with a disk editor and changed a bit in the directory that wasn't normally accessible. It may have been "File may not be deleted or extended" or some such thing. So there was a zero block file called LP, so no more problems for him to fix.
Me and two friends were the main speakers at a local DECUS meeting. We each took as aspect of file systems and talked about it
Since where I worked had source files for RSTS-11, we had fun making modifications. I orchestrated a design of a better terminal handler especially for CRT terminals and another friend coded it.
Hacking in high school got me a job there. I could crash a system in about 30 seconds.
I used an 11/20, 11/50 and later I self-maintained 11/2, 11/23 and 11/23+ systems running RT-11. DEC had a nice fixed price repair deal. You send a card and you get another back immediately for a fixed repair cost. There were only two of us that could do those repairs though,
The 11/45 had a really nasty problem. It would drop a bit in the Processor Status Word when it switched modes (user and Kernal). I found that issue, From there DEC service was able to fix it.
The 16B (IIRC), maybe?
I learnt PICs with it and the 16C57.
Coincidentally, a few days ago whilst digging for a spare IC, I happened to come across some of the old EPROM PICs we used to use for development work.
The earliest ones are 25 years old, from the date code.
I never had to do anything "serious" with them. It was much more about "these are cool, how do they work".
I took this pic a few minutes ago.
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It is a binary clock that ran off of the 60Hz voltage "tick" after it was stepped down with a transformer (pretty accurate actually). I was tickled pink when it worked and still have the code print out somewhere.
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If I am not mistaken, that is a 1993 date code. That means that the circuit has been on a breadboard for ~25+ years - a personal best!!