Got this from a friend of mine:
I've never heard of an HP2250 either, but according to the 1983 HP
catalog, the HP2250A is a "Measurement and Control Processor." It's
designed to work with the HP1000 and HP9800 computers via an HP-IB
interface, and accommodates a series of plug-in cards for measurement
functions (like multiplexers, A/D converters, counters, relay cards,
etc.). It has "a built-in LSI microprocessor and MCL/50 firmware, a
software command set comprised of over 100 applications oriented
mnemonic commands that can be used in many combinations to optimize
measurement and control operations." Apparently, you program it using
the host computer, then set it loose on its own to gather data and
control devices. Interesting...
Joe