30 Jul
2007
30 Jul
'07
9:24 p.m.
On 7/30/07, woodelf <bfranchuk at jetnet.ab.ca> wrote:
Ethan Dicks wrote:
The F20 is a TTL implementation-from-specs of the PDP-8/i as a series
of chapters and homework in "The Art of Digital Design", Prosser and
Winkel, Prentice-Hall, 1987. I got my copy from Abe Books a few years
ago and have been reading it as bed-time material this month.
The F20 uses 74181 ALUs and 74183 adders as the center of a TTL PDP-8.
The F30 (later chapters) is a re-implementation of the same
instruction set using a microprogrammed design and an AMD2910.
Given how hard it is to find an IM6120 in the wild these days, a TTL
PDP-8 sounds attractive to me; as long it can address more than 4KW
(which I don't think the stock F20 or F30 does, so there's more
homework to do).
-ethan
I've been re-reading a book on processor
design I picked up a few
years ago, based on a recommendation on this list. I am blanking on
the title, but it describes a 74183/74181-based F20 and a 2910-based
microprogrammed F30 PDP-8/i-compatible CPU. I've been mulling over
what it would take to build one of those (besides lots of time ;-)
What is a F20?