computers I used
Here I am speaking of hardware, and I am
mainly listing computers I have worked with:
- mainframe IBM in the early 1970ies,
I've also seen this computer, but the actual
programming of that day consisted in writing code for punch-cards in Algol
or Cobol, handing this to the technician who took care of the computer, and
wait for a line-print of the output.
In the late seventies a friend bought a
SIM-computer - which was in effect a motherboard with some chips and other
electronics, with a LED-screen on it, for 8 characters or numbers.
To program it, on had to write machine-code
for it. This was theoretically interesting, but not productive, and also
expensive, since it cost much more than a Texas-Instrument electronic
calculator of the day, while it could do little more.
Around 1980 the same friend, after
discarding the SIM, bought an early Apple. This came with a 14 inch
green on black screen; one could code AppleBasic for it and see the
results; and one had to store the programs one wrote on the tape of a
This was quite amazing and it also
allowed one to do things that were more difficult to do on paper, such
as - in my case - drawing and calculating truth-tables for
In 1987 a girl friend who had a father
working for Philips as a middle manager got his Osborne, that dated
from 1982 or 1983, which was one of the first computers that were
meant to be laptops - i.e. computers one could easily carry around
In fact, the Osborne when packed for
travelling looked like a hefty sewing machine in its box, and when
unpacked had a keyboard and a 4-inch screen, though one also could
connect it to a screen like the Apple used.
This machine ran CP/M, and came with
Visicalc and Wordstar. Visicalc was one of the earliest spreadsheets
and Wordstar one of the first text-editors. Both were amazing,
and made the Osborne a really productive tool.
Its memory was 64 or 128 Kb (I forgot),
minus what CP/M needed, and I think its processor ran at 0.6 Mhz, but
it was a great introduction to personal computing.
The Osborne was rapidly followed up 1987 with a Philips with all of 256 Kb of
memory and an early DOS operating system.
This was the first PC-clone I worked with, and it was more powerful and faster
than the Osborne, and also ran more powerful software, but the early graphics
was awful: Very big pixels in 4 ugly colors.
This again was rapidly replaced by several
other Philips PC-clone, ending up with
which did have 640 Kb of memory (minus what
DOS 2.1 needed) and a 20 MB harddisk.
The graphics was not as awful as on the
earlier Philips, but still not really pretty or much use, but this computer
could run Lotus, Paradox, Quattro, dBase III Plus, and any other program that
made the PC useful and productive, and also could run DesqView, which gave the
illusion of multi-tasking in DOS.
In the university I had some experience with
early Macs (rectangular boxes with rather small black and white graphics
screens) but I never got my own Mac because it was expensive.
Then the internet arrived, and I got a 486
computer, which was replaced in time by a Celeron or Pentium clone and
These were bought to run Windows95 and
Windows98, which were the first graphical systems (as opposed to text-based)
that Microsoft produced that one could productively work with, and that got
popular very rapidly with PC-users because of the internet and because of the
much more pleasant looking interface.
The main problem with Windows95 and
Windows98, regardless of the hardware these ran on, was that these crashed
often and unpredictably, and also regardless of what one did.
I used variants of Windows95 and Windows98
from 1995 to 2002, and hardly a day passed without a few crashes. This was
annoying, and could be very annoying. Thus, when trying to program some Java
in Microsoft's very own J++ around 2000, this crashed Windows98 and trashed 45
MB of data on the harddisk, which took a lot of time to recover from (and
quite a lot was permamently lost).
At present and since five years I mostly use
a Hewlett Packard computer with Windows XP, which is a combination that, for
the first time with Windows, is rather stable (it rarely crashes) and that has
been free for years from major bothers due to the hardware or the OS.
This is not a powerful machine anno 2007, but
it runs at 1400 Mhz, has 256 Mb memory, and can show films and write CDs -
which when compared to the Osborne I started serious computing with in 1987 is
an enormous difference.
And it is an interesting fact, that
illustrates both Moore's law and free market competition, that ever since the
Philips 286, the price of a new computer that I bought was lower than the
price of the previous one, whereas its capacities in terms of processor speed
and internal memory were usually at least double of the previous one.
I am no gadget-freak and never was one, nor
am I interested in hardware per se or in tinkering with it, but it is good to
have some knowledge of the hardware one uses. Here is a commented list of some
books I have found useful over the years.
What I am concerned with is knowledge and
understanding of some general principles involved in hardware, and it so
happens that I found the following relatively dinosaurian books quite useful:
- Digital Computer Basics - Prepared
by the Bureau of Naval Personnel
This is a training course for U.S. Navy
Personnel, that was printed by Dover Paperback in 1969, and that has the great
merit of explaining the basics really clearly. It is about mainframes, but
this does not matter in principle.
- Home Computers: 210
Questions & Answers - Volume 1: Hardware - Rich Didday
This text is from very really early days,
since it is from 1977, but it is quite good and clear, and also gives a taste
of what "home computing" was like around 1977: It needed a lot of careful soldering
and patience by the user.
I mention these texts because they helped me,
and because they are - still! - quite good about the basics, that indeed has
not changed in principle ever since Von Neumann designed the outlines of a
modern electronic computer.
The above two books are mainly practical
apart from explaining binary arithmetic, basic programming etc., but the next
two books give some basic knowledge of principles.
- Assembly Language from Square One -
This is from 1990, and is a good introduction
to Assembly for those who know little or nothing about it to start with.
If you want to understand the basics of what
a computer can do, you have to understand some Assembly, and this book
explains the very basics quite well.
- Computation: Finite and infinite
machies - Marvin Minsky
My edition dates from 1972, and is a very
clear introduction to the science of computing as far as mathematics and logic
are concerned: It explains what a computing machine is, mathematically
This does not give one hardware knowledge
properly speaking, but it does explain very well what the computing hardware
one uses embodies in principle.