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Re: micro processor vs controller


>dust.  MuP21 already works, and it sounds like i21 and F21 will also
>soon work, and there's no reason to think that .25 micron could not
>yield chips that ran at over 2GHz.  Perhaps I'm being really naive, but

When running something at that high a frequency, stray capacitance and
inductance can become a monumentally major problem.  Furthermore, the CPU
itself will get warm (possibly quite hot) just from microwave radiation
alone.  That CPU had better be shielded well, lest someone get an RF burn
from the chip...

The die would also have to be much larger than it would be now (to combat
stray capacitance); but you can't make it too large, lest you introduce
stray inductance in the wiring.  Furthermore, the skin effect requires a
thicker metalization layer as clock speeds increase...

In short, a 2GHz F21 would be possible (make no mistake); but it sure would
take quite some time to develop, and it most definately WOULD be a lot more
expensive than the current F21 price (whatever it will be).

Then, of course, there's the issue of interfacing the chip with the outside
world; I don't foresee a 500MHz bus just to keep a data cache filled; at
500MHz, a data bus makes a wonderfully good transmitter for UHF radiation.
Again, the PC boards must be shielded to prevent accidental RF burns, and
safety interlocks should be in place.  And at anything over 500MHz you had
BETTER have an on-chip data/instruction cache (preferably Harvard
architecture)!!

>I don't know what you're talking about; there is no way an MuP21 would
>get hot enough to cook your toast.  I have a feeling a F21 wouldn't,

I think that's what he meant... ;)

>I usually agree with you, but this time I really must take Bill's side. 
>I think a Pentium PC running MS Windows is an excellent idea for cooking
>toast.  Cooking toast is about all a Pentium PC running MS Windows is

Pentium ][ is much better at cooking toast than Pentium or Pentium Pro.  The
Pentium ][ also cooks T-bone steaks, and can replace your incadescent lights
with a longer lifetime.

>solder some sockets into the board.  That's when I noticed that, like an
>idiot, I had designed the board with the chips too close together and I
>couldn't physically fit the sockets into the board next to each other
>where they needed to go because they were too big.  Don't laugh.  These

Hey!  You never told me about this in your private e-mails!!  :)
=============================================================================
"Tongue Tied and Twisted, Just an Earthbound Misfit..." - Pink Floyd

Long live the AMIGA!!        HAM Radio: KC5TJA/2, Tech +, 145.450MHz Repeater
http://www.borg.com/~falvosa                                Utica, NY  [FN23]

     Project Leader: Dolphin Operating System (mailing list: ddg@qzx.com)

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