cowan@udel-relay.arpa (03/01/84)
From: Ken Cowan <cowan@udel-relay.arpa> I'm sorry for the misunderstanding. The only MicroVAX x that I had heard about was the product. Since I generally follow products, nothing about chip sets has crossed my desk (even if the chip set is a single chip). It has been rumoured (in my circles) that there is a MicroVAX II and a MicroVAX III in engineering. Again, these are products. Are these products the commerical arena for the new chips you have heard about? Ken
phil@unisoft.UUCP (03/06/84)
WE ARE TALKING ABOUT SEVERAL DIFFERENT THINGS HERE FOLKS!
(1) DEC has a multi-chip ``microprocessor'' implementation of the VAX.
It is slow. It emulates some things in software, and DOES NOT have
a ``full'' instruction set. This (I think, I DON'T know) is what has
already been announced and referred to as the microVAX.
(2) DEC talked about at the ISSCC, a 11/780 type VAX implemented in
a chip set. This machine has the full, 100%, it's all there, VAX
instruction set. It has a FPA chip (not yet done). It runs as fast
as a 780 +-. Multiply slower, divide is faster, etc...
Dick Sites, of DEC, a figure in the project, gave a talk at Berkeley
about this. Project was started 4.5 years ago. Apparently, from what
I heard in the talk, was that the ``MicroVAX'', in (1) above, uses
the ``execution unit'' of the 780 set, and a lot of software, to
provide a much-slower VAX. This was done as not all the chips are
becoming ready at the same time. Availibilty of this ``780 chipset''
is unknown. Dick stated that as of ISSCC, all of the chip sets for
the 780 have come thru fabrication. He actually held up the ``very
first'' wafer full of one of the chips in the set. It apparently
came out just before ISSCC. Thus, by ISSCC time, all of the 5 chips
that make up the 780 chip set have come thru fabrication.
Dick gave some amusing tales about how the complexity of everything
broke most of the CAD tools at DEC and had to be rewritten.
NO AVAILABILITY or other useful info was talked about.
(3) Therefore, this ``780 chip set'' and the 68020 seem to ready to
battle it out 4Q 84 or 1Q 85. Note that the preliminary manual on
the 16MHz 68020 show it to be much faster than a 780. This could
be real interesting.