Re: Another New Hardware Thought

["Michael J. Mahon" <mjmahon@aol.com>]

Charles Shannon Hendrix wrote:
> On 2007-05-04, Michael J. Mahon <mjmahon@aol.com> wrote:
>
>
> > I agree--though it was also quite common to be a Computer Science grad
> > 20 years ago and to know nothing about the inner workings of computers.
>
>
> Not in my school... we called those guys "IT Majors".
>
> I had to take computer architecture to graduate.
>
> I suppose I could have found a way around it, but they made it
> difficult, and I didn't want to anyway.

That's good!  My guess is that you went to an engineering school,
and that their CS program emerged from EE.

In the 1980's, many CS college grads had *no idea* what the hardware
had to do to evaluate their favorite Pascal statement.  ;-)

> > In many schools hardware was considered a necessary evil, and software
> > was a branch of mathematics!
>
>
> Well, that's how it started out years ago. There was no computer science
> degree program until years after WWII.

Of course, but I was talking about when there *were* CS grads...

> > But the real obstacles to complete understanding modern systems are
> > 1) their inconceivable complexity (yes, even their designers don't
> > *really* understand their complete workings), and 2) their vanishing
> > physicality--there's nothing there but a sliver of silicon, WITH OVER
> > 100 MILLION TRANSISTORS, SWITCHING OVER A BILLION TIMES PER SECOND!
>
>
> Yes.  No test points, and it is hard for you to make modifications to a
> system.

Which is what I meant by "probeable".  If you can't inspect the
signals on the wires, you can't get a concrete understanding of
the functioning system.

> > They could experience its behavior as a "black box", they could "take
> > off the top" and examine and probe the insides, add and remove cards,
> > and even "construct" virtual cards to plug into it (for extra credit).
>
>
> True, but there really is nothing like the real hardware.
>
> Systems that can be expanded or modified with discrete logic give you a
> physical understanding, and it is also a lot cheaper.

Exactly, but unless you are willing to use 74-series chips, there is no
such thing as discrete logic anymore (as you allude to below).

> Yes, you can create a chip mask and send it off to be built, but you
> have to be wealthy to afford that.
>
> About all you can do at the hobby level is FPGAs, and that's pretty
> expensive, and difficult.

And much more like software design than discrete hardware and circuits.

Most people would have to look closely at what an engineer is doing
on his computer to tell whether he's designing hardware or software.

> One of my goals in life is to build my own computer.
>
> I am trying to think of a way to do it in software, hopefully some that
> can save hardware designs to let you build it for real when you are
> done.

All hardware design is "done in software" these days, so you won't have
any trouble getting your wish.  ;-)

-michael

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