>I know its off-topic but i figured that since most of the poeple on this
>list work or have worked on the really big stuff you'd know better than
>most others.
>
>Say someone were to home-build a CPU from scratch using only individual
>components, no ICs only modern descrete(?) components. How big would the
>CPU be? For comparison lets say it would be an 8080 clone. Any guesses?
Well, others have guessed at the 8080 Clone, but I'll step in and point
out that if minimal part count is an important feature, then you can
get by with a *lot* less. Especially if you go to a bit-serial
architecture. (Something that's still mentioned in many computer
architecture textbooks, even if it isn't used much anymore!)
How big? I'll venture a guess that a 12-bit serial CPU
could be done on one largish (i.e. a square foot) PC board, using
TO-92's, resistors, capacitors, and diodes. This isn't too far
out of line with many bit-serial designs from the late 1960's
(for example, many bit-serial desktop calculators used a PC board
- or two or three - about this size.)
Total cost? Maybe $1500 in large scale production, including testing
costs.
Of course, you now hook up memory to this CPU. Doing that with
discretes would be a chore!
--
Tim Shoppa Email: shoppa_at_trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
Received on Wed Oct 20 1999 - 09:14:58 BST