20 Oct
1999
20 Oct
'99
3:46 a.m.
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.
With gating and interconnect it will grow.! Also that would be a CPU chip
replacement... memory, IO and control pannel would be needed.
I think the key is yes it can be done. Yes with moden discretes and
technology you can compress it. However the devil is heat and a SMD
transisor at 10mW per is going to get hot with 40 per board! Why 10mW?
You have to drive wires and other gates and these are not MOS devices like
on the chip (you can but you still used real resistors) so things like
fanout/fanin are considerations.
While there are small serial computers a look at them shows some things
that need to be reflected upon. They were serial archetectures and
minimized the used of things like registers as they were hardware
intensive. The Minuteman Missle computer I"d played with many eons ago
was such an example. Flipflops were very scarce in that machine.
Allison