Corrections to trivia

From: Allison J Parent <allisonp_at_world.std.com>
Date: Tue Oct 6 06:52:51 1998

< allisonp_at_world.std.com (Allison J Parent) wrote:
< > The F8 (NOT the 3870) had bits and piices of the CPU scattered between
< > minimum of two chips.
<
< No, it didn't. The entire F8 CPU was on a single chip. If you added a
< chip that contained only ROM and I/O, you had a functional system.

Not quite. the F8 cpu (3850) was an incomplete system without the
385x (3851,6,7 PSU). It was very difficult to simulate the PSU in ttl
as well. The two ran in lock step just like the parts of the F14 CADC
or the LSI-11 with it's MICROMS. The 3870 was the single chip version
of the F8. In some respect the F8 was like many early parts in that the
CORE CPU was there but glue was needed to make it all work.
(8080/8224/8228 for example).

I know this from doing comparative design-ins while at NEC during the
late 70s.


Allison
Received on Tue Oct 06 1998 - 06:52:51 BST