The SEL 840 computer 4047

what year?

Over 100 minicomputer (as in small address space) companies existed. A somewhat nice tree-poster exists with many of these firms.

.... Not likely. Mercury was really old and Minis were struggling with 16-bit, but I would need to see the context.

It was more interactive and mini like than mainframe, cards, batch CPU like.

The typical justification for buying a SEL, a Prime, a DG was that it ran a factor of 2-3 faster than DEC machines for very slighty higher prices and far less software (you were lucky to get a bare OS typically tuned for real-time (except Prime for instance), an buttembler, and a Fortran compiler, and a link editor).

SEL was really big with the DOD beltway bandits crowd.

Their last major system, the NP-1, had a secure Unix in which they challenged crackers to get root pbuttwd for a major (maybe $100 {still the 1978 RSA prize}) chocolate prize (back then 80s). I think that someone wrote a quick Trojan horse which fooled their booth person enough to compromise root. They cried Foul! but paid up. SEL was probably savvy enough to have a UUCP feed and contact info in the dark recesses of archives.

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