clipka wrote:
> Even then, you'd have some log8(N) dependency of gate levels needed, 
> where N isn't even the amount of memory, but the number of address lines.

I'm not really following...

> 1 level:   8 address lines - up to 256 words (*)
> 2 levels: 64 address lines - up to 16 Exawords

Except ... you need that fan-in for each word you address. Now you have a 
problem of fan-out, as well, if I'm visualizing what you're saying correctly.

In theory, any logic function (including an entire CPU) can be built from 
two levels of gates. In practice, the fan-in and fan-out kills you, because 
you can't have 256 fan-outs going into each of 256 additional gates.

-- 
Darren New, San Diego CA, USA (PST)
    Eiffel - The language that lets you specify exactly
    that the code does what you think it does, even if
    it doesn't do what you wanted.

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