newbie building a scratch-built computer

[Roy J. Tellason]

On Wednesday 01 August 2007 18:18, Tony Duell wrote:
> > > That sort of thing tends to not have very much use in today's job
> > > market, unfortunately.
> >
> >    That's absolutely correct, because most HR drones don't actually
> > look for people who know anything about computers.  If Joe wants to
> > learn something about computers, as opposed to learning only what's
> > guaranteed to get him a job in a suitly company, then I very strongly
> > recommend that he pursue the path that he discussed above.
>
> The problem comes from the fact that there are only a finite number of
> seconds in a day :-)

Indeed.

> . If you're not careful you can end up in my position, knwoing a bit about
> things that nobody seems to want, but not having the right buzzwords on your
> resume to actually get a job. 

That sure sounds familiar...    :-)

> >    Joe...As for your not being hopeful about building a TTL-based
> > computer from scratch...The knowledge required to do it is readily
> > available.  If you REALLY want to do it, you can.  Your father's
>
> I will second that. I am living (?) proof that it's possible to
> understand this stuff. It didn't take me _that_ long either.

TTL can be fun.  I breadboarded a three-chip setup once with a 555, a 7400, 
and a 7474 that sequenced four LEDs.  Stuff like that...

> > assertion that he couldn't do it after six years of college is really
> > irrelevant here...not many college EE programs teach anything about
> > low-level computer architecture, and sadly, even fewer CS programs
> > do.  Learn about boolean algebra, learn about Karnaugh maps and other
> > minimization techniques, learn about combinatorial and sequential
>
> And learn to do it 'by hand', not just using CAD tools. The latter are
> undoubtedly very useful, but knowing how to do things by hand will let
> you know when said CAD systems have made a right mess of your design.

Over and over again I see newbies struggling with what they're trying to do 
and what the simulation is telling them should be happening,  which isn't 
necessarily all that connected to the real world.

> > logic...not only will you be able to design and build a TTL-based
> > computer, but you'll end up knowing more about *computers* (as
> > opposed to "how to install Microsoft products on PCs") than most
> > anyone churned out by today's colleges.
>
> It's a great pity the latter is all most people care about. It is,
> perhaps, a little worrying that I am classed as computer-illiterate....

>From time to time we get a mailing from the local community college,  and 
that's all they seem to cover in there--- m$ products,  to a few different 
levels.  Nothing beyond that.  It's downright scary at times.

> [I choose not to use Microsoft products, or much commercial software at
> all for that matter, for what I consider to be good reasons _for my own
> situation_. 

As do I.

> Yes I could learn how to install and use such programs, probably in a couple
> of afternoons. And I'd like to see any of the so-called PC experts
> understand a microcode source listing in the same length of time :-)]

:-)

> >    Further (also directed at Joe)...As you already very obviously
> > know, it's actually possible for one to learn something without it
> > being spoon-fed in a school.
>
> Very much so! Now, how do you convince droids of that? Both the sort that
> try to enforce bogus safety regulations ('No, we can't sell you that
> spare part, you're not trained to fit it' when actually I could _make_
> said part in an hour or so...) and those that work in HR departments 'No,
> Dr Duell, you don't have the right qualfiications for this job' meaning I
> don't have some bit of paper saying I know how to turn on a PC, even
> though I routinely design such things...)

That's why I'm doing what I'm doing just now,  a very non-technical job,  but 
at least it's helping to pay the bills....

-- 
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space,  a critter that can
be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James 
M Dakin