> 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.
Well, I can't deny this...
> 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?
According to the intel Web site an 8080 has about 6000 Transistors.
Now, it is possible to put up some 12 to 16 FF gates in discrete
logic (discrete non SMD transistors etc.) gates (~40 Transistors)
onto one Euro-Card board (I tid once build up 16 FFs on one board
- at the age of 16, I tried to miniaturize :). So, spreading 6000
transistors at 40 transistors per board gives some 150 boards.
And with an asumption of 20 boards per row we need some 8 rows,
or a small (half height) rack.
As usual YMMV - especialy if you may change the design. And/or
build individual boards to maximize the number of transistors
per board (and of course try to replace as many as posible by
other circuits with less components).
For the 6502, the numbers are similar. I don't have a transistor
count, but a standard SC02 design consists of roughly 3,300 Gates,
adding up to a number like again 6-7,000 Transistors (BTW, the
65sc02 as PLD needs ~2.1k Altera Logic Cells, or ~1k of xilinx
LOgic Blocks).
Gruss
H.
P.S.: I scored an unused 8008 Processor last week - among a bunch
of other late 70s/early 80s chips...
--
Der Kopf ist auch nur ein Auswuchs wie der kleine Zeh.
H.Achternbusch
Received on Wed Oct 20 1999 - 10:47:13 BST