So, where do
you draw the line? I draw it at one piece of silicon that
can stand alone with the usual support chips (ROM, RAM, glue chips).
I define a microprocessor as either a single chip processor, or as a
small (to be defined ;-)) number of chips which are only ever used
together to make a particular processor.
Yes, I agree with that one. Slight grey area here - things like the
floating point unit in the LSI11 or the CIS in the KDF-11 - are they
part of the microprocessor chipset or are they coprocessors?
Byt that definition, anything built out of TTL, 2900
series, 3000 series,
etc is _not_ a microprocessor. Those chips have uses other than for
building that particular processor. But the F11 (PDP11/23) is - that
chipset only ever gets used to make an 11/23 (or an 11/24 for the pedants
:-)).
So is the early IBM RISC 6000 processor. I seem to remember that's 8 or 9
packages, but I would still class it as a micro.
Other people insist a microprocessor is one chip only. I've got no
So I notice. But by that definition _none_ of the micro PDPs were true
microprocessors, or at least none up until the 73. The Micro J-11
processor in the 73 was implemented as two chips on a large ceramic
carrier. Was this also the case with later J-11s?
Philip.