Early minicomputers were part of the electronics business itself.
Witness the Fairchild Sentry ATE gear using the FST-1 minicomputer at
around the time that Fairchild was rolling out its TTL and Macrologic
lines. 24-bit more-or-less general-purpose. I believe I wrote about
what I'd deduced about the thing before Al uploaded some valuable
information on it.
AFAIK, there's still a manufacturer in Israel still using one of the
bed-of-nails Sentry test setups.
--Chuck