I most certainly don't mean to offend, in fact not being offensive
in any way to anyone is one of my life long goals - and one I'm
continually improving at;). I had an instructor in tech school that
taught me that we all abstract reality up to the point were happy
with our understanding of things. Think about it. Most people - even
technical folks like us - we really don't understand what's going on
at all levels of, say, a hard drive. I'm smart enough to know that
every byte on a hard drive might consume more that 8 bits, and that
the term bits don't really apply at all to what's going on in the
"magnetic domain". It's all analog down there. Above that layer of
abstraction there are many different encoding schemes used for
redundancy and reliability, partial response most likely answer
might be an example. Below the analog level, at the atomic level and
the subatomic level all sorts of complex things are occurring that
probably only a few scores of people understand, like how magnetic
domains might interact with gravity waves at the quantum level. I
don't have time in my day for everything I need to learn now - much
less time to study and understand drives at this level, thus I've
abstracted them - in my little week mind - down to the point that I
don't even think about the lower levels, I just think about how I
need to use them to accomplish my goals, now - today. Yes, I still
set and think about these lower level of abstraction sometimes, but
I'd be more likely to set and think about why we can't get cheep
SCSI drives with multiple head actuators with multiple heads per
actuator. My boss doesn't need to even worry about any of the above
to do his work, so he as abstracted the whole process to a point
about 6 or 7 levels above me, namely
"Create Unique Clustered Index GoshDarn on LidMasterSales
(DTE,CUSTNO,PROD#,DEX_ID)
Now that's about as abstract as it get! But it sure works for him,
thus I see nothing "bad" about abstracting something complex (notice
I didn't say complicated) to the point of usefulness - and it just
strict me how long this post is getting. Sorry for the wasted
bandwidth folks, it must be the Canadian Club again.
Logic analyzer eh? Must be nice! BTW Tony, I'm just starting on
this IEEE-488 trek and wonder if you could recommend some good
reading material to start out on. My goal is basic understanding and
the scope is instrument and test control. Thanks.
Roger Goswick
-----Original Message-----
From: CLASSICCMP-owner(a)u.washington.edu
[mailto:CLASSICCMP-owner@u.washington.edu]On Behalf Of Tony Duell
Sent: Thursday, July 29, 1999 5:36 PM
To: Discussion re-collecting of classic computers
Subject: Re: Tek 4041
4041 to use a serial port as the standard programming
I/O port.
And
of course I never meant anything ill about process
control or the
IEEE-488 bus(HP-IB - GBIBP whatever), but I have noticed that a
lot
of folks do seem to look down upon machines that they
have (in
their
minds anyway) abstracted down to nothing more that
simple black
boxes. Learn everything their is to know about a Commodore C-64 or
even a Motorola D5 board and you have acquired more knowledge than
most windows programmers about what really is going on, think?
I don't follow this at all. To me, GPIB is just another 8 bit
parallel
interfave that I can send bytes over. It's got 8 data lines, 3
handshake
lines, 5 control lines. That's it.
I don't 'abstact' anything down to a black box. I think in terms of
the
signals on the logic analyser screen, the registers in the GPIB
controller chip, the state diagrams in the IEEE-488 standard.
You're right - I do (as do others here) like to understand what's
going
on inside my machines. But I don't see how GPIB prevents me from
doing this
-tony