but we are unable to help you on this
point.
Normally, you should be able to
print the READ.ME file by typing
“COPY READ.ME LPT1” and then ENTER. If you can no longer do this and
you can no longer read the file using
the TYPE command, it suggests that
the file has been corrupted.
If you wish to run a program written in C on your computer, you must
have a C compiler, such as Turbo-C
or Turbo-C++ by Borland in order to
run it. All programs, no matter what
language they are written in, require
an interpreter (such as is used in the
Basic package on your machine) or a
compiler. Programs written in C do not
run using interpreters so a compiler is
the only way. In effect, a compiler converts high level language to machine
language which can be “understood”
by the microprocessor.
Needs circuit for a BWD
scope
I am writing to you in the hope you
or one of my fellow readers can help
me. I have a BWD 539D oscilloscope
which is out of order and need a circuit diagram. I need to know where I
can get in touch with the distributors,
or if any reader could help with a
copy or the original service manual
for which I would be happy to pay.
(Bob Riding, 65 Pacific Bay, Fingal
Bay, NSW 2315).
Notes & Errata
Remote Control Extender for VCR’s;
April 1994: the panel mount DC socket
for the plugpack should be an insulating type to prevent the negative pin
shorting to the case. This is shown
in the photograph on page 21 of the
article in the April issue.
Induction Balance Metal Locator; May
1994: The parts list should indicate 5
rather than 4 0.1µF MKT capacitors.
The extra capacitor is shown on the
overlay but not on the circuit. It is
used as a bypass to ground for the
+7V supply near VR1. The .001µF ca
pacitor shown on the overlay next to
VR1 should be .01µF.
Champ Audio Amplifier; February
1994: the text on page 47 regarding the
“blurt” test should read “You do this
by winding the trimpot anticlockwise
and then putting your finger on the
input”.
SC
The Emperor’s New
Clothes: from page 29
understanding. Many idiosyncratic
system behaviours that plague us are
actually cracks in the thin veneer of
standards compliance infrastructure
through which the designers actual
implementation shows through. It’s
a bit like catching a glimpse of the
puppeteer pulling the strings behind
the ‘Punch & Judy’ show.
Second, people take short cuts. Ever
noticed how some of your old software
suddenly stopped working when you
compressed your hard drive with Dos
6.2? All those programmers were too
clever by half and decided to bypass
the service routines provided and run
their own show. The tendency to take
short cuts is partly due to the unseemly
haste with which products have to be
brought to a fad driven market and
partly due to a basic flaw in human
nature.
It goes something like this. A committee (a group hell bent on detailing
the creation out the door, there isn’t
much motivation for anyone to tidy
up the blueprint.
So what do you do if you see a “dinner retrieval kit complete with burger
cam”? Ask yourself the question, “Do
I really need this?” If yes, then comes,
“Have I seen one of these actual
ly
working in the real world?” If no, then
“What background do my associates
and I have with this technology”.
If you actually purchase the thing,
unwrap it very carefully. That way you
can always put stuff back just like it
was when you can’t get it to perform.
Now return it and make out like you
never really had time to try it anyway.
Act casual, disinterested even. Popular
culture dictates the more aloof and
distant you are, the more in control you
must be. If they get stroppy, remind
them about current consumer legislation regarding the onus to source goods
of merchand
isable (read: it should
work) quality.
The Emperor’s new clothes are indeed magnificent. Not only are they
grand but they are mix and match.
“The tendency to take short cuts is partly due
to the unseemly haste with which products
have to be brought to a fad driven market and
partly due to a basic flaw in human nature.”
a camel when the specification calls
for a horse) decides on a procedure
or protocol, an agreed way of doing
things. Before they have even finished
their deliberations, usually, the wider
community of participants has figured
out a better way of doing things.
If the new way is really spiffy, everyone just ignores what the committee
says and the improved approach becomes the de facto standard. But often
the new approach is more human ego
than efficacy. It’s a little bit better or
just a bit quicker, conformity sacrificed
on the altar of that perverse human
need to “do it my way”.
Lastly, there is the problem of documentation. This relates again to the
factors mentioned previously, human
nature and haste. Most design teams
start out with a blueprint of what they
want. They build it and it doesn’t
work. So they spend ages tinkering
with the entrails until it does work.
Then in the frantic scramble to get
“This goes with that,” all inter-connectable, compatible and groovy
because of the underlying open architecture of structure and function.
Everyone agrees that it must be so.
The collective will of all those people
makes it the case. I rest my case.
I scanned in a little pic for this article but the scanner software won’t
load it today. It loaded fine yesterday.
But then I’ve done a tape backup in
the interim.
I really do use my scanner and
tape backup so I’ll have to pursue the
issue. Of course, the suppliers can’t
help so I’m on my own again. Mind
you, I’m lucky this time, I think I
know what’s actually going on with
this one. I should have it sorted in
SC
no time.
*Kris McLean is the principal of
McLean Automation, a firm special
ising in data transfer technology.
June 1994 93