How computers REALLY work

Copyright Dr Alan Solomon (1986-1995)

The  computer  manufacturers  try  to fool us into thinking that their
machines work by electronics.  That's rubbish - just another of  their
jargon  words.  Computers really work by magic, and to understand them
properly, you have to understand a bit about magic.

Most people claim that they don't believe in magic, but if  you  judge
people  by  what  they  do rather than what they say, you'll see lucky
charms, worries about ladders, Friday the  13th,  astrology,  touching
wood,  fingers  crossed  -  people  clearly believe.  And the simplest
explanation for all this belief is that they are right - magic  works,
at least, some of the time.  Nobody expects magic to be 100% reliable,
and it is this that gives us the first clue that computers  work  that
way.

First,  some theory.  Magic isn't formally taught in many places these
days, so although people know THAT it works, they don't  know  HOW  it
works.  A better understanding means that you can choose better magic.

First, what is magic?  Magic is an attempt to control the objects  and
people  around  you,  without  the use of direct action.  Any fool can
break his back digging holes for a living, but by using magic, you can
sell a floppy disk that costs perhaps #1, for #595.

There  are  five type of magic.  The first is sympathetic magic;  this
is also the one that most people have  heard  of.   Sympathetic  magic
works  by  operating  on  a  simulacrum  (or model) of the thing to be
controlled.  Voodoo is the best-known form of sympathetic  magic,  but
the  UK  Treasury  also use it to manipulate the UK economy by using a
computer model.

The next kind of magic is nominal magic - working on something's  name
causes  the desired effect.  This is why in some societies, a person's
true name is kept a deadly secret.  This is  not  used  much  in  most
walks of life, but in the computer field, it is used extensively.  For
example, this is why so many products are called  Desktop  Publishers;
using nominal magic, calling it a silk purse makes it one.

The third kind is animistic magic.  A thing has a being inside it, and
by proper appeasement/bribery of the being, the thing can be  made  to
do  what  you  want.   The  fourth and fifth kinds are black and white
magic;  white is merely the reverse of black.  Astrology is  somewhere
in between the two.

Older magic is generally more powerful than newer magic, and the older
the better.  Some of the newest forms of  magic  hardly  work  at  all
(such as modems), whereas the oldest magic is extremely reliable (like
desk calculators).

Now that we have an elementary grasp of magic, we can understand  more
about  how  computers  work.  Notice that by merely assigning names to
the different kinds of magic, you  already  feel  you  understand  it.
This  is  nominal  magic  at work;  now perhaps you see how powerful a
simple bit of magic can be.

HOW COMPUTERS WORK

At the centre of the computer is the 8086 chip;  this is  very  strong
magic  indeed.  Silicon is very old, as it is the stuff that the earth
itself is made of, and Intel use a very powerful spell to put a  being
into the silicon.  Careful examination reveals that there is in fact a
miniature troll inside the chip;  trolls have a  strong  affinity  for
rock,  and  are extremely powerful.  Intel also sell other chips - the
80286 is larger, because it has a larger troll in it.  This  troll  is
also  hungrier,  so  the bytes are larger;  16 bits each compared with
the 8-bit bytes of the 8088  troll.   But  the  troll  needs  help  to
channel  its  raw  power  into useful work, so Intel sell a variety of
chips that act as a harness to the troll.  For example, the  Interrupt
Controller  (which  has a lesser troll inside it) is used to interrupt
the troll whenever he needs telling what to do.  There is also a magic
Crystal,  that  beats  time  for  the  troll, so that he can work at a
steady pace.  The Crystal works at a rate of 4.77 beats per twinkling,
although  more powerful magic Crystals have been developed that can do
8 or even 10 beats per twinkling.

The floppy disk drives are not directly controlled by the troll.   The
troll  sends  messages  to the floppy disk controller (FDC) about what
the disks should do;  the FDC has a  model  of  the  disk  drive,  and
controls  the  drive  by sympathetic magic.  The FDC also uses nominal
magic on the 8088 troll;  note the use of the word "troll" inside  the
name  of the card.  This makes it possible for the FDC troll to access
memory directly, so making disk transfers very fast.  The hard disk is
controlled in a similar way, but uses a Kobold.

The  other  major  hardware  is  the  screen.   This  was developed by
Motorola, and uses naiads.  The naiad is a kind of  water  nymph,  and
she  puts the letters on the screen to correspond to the messages that
the troll leaves for her via the 6845, which is  used  as  a  kind  of
carrier  pigeon  up to the screen.  Naiads are deft and nimble (unlike
the slower but more powerful troll), and a good naiad can replace  all
the  letters  on  the  screen in about a thousand twinklings, although
some programs make her fetch the letters one at  a  time,  and  so  it
takes her a lot longer to fill the screen.  She keeps the letters in a
box called the "Character ROM" - there are enough there to last a very
long  time,  but  when  they  are  used  up,  the  ROM will have to be
replaced, obviously.  To stave off the day on which she runs out,  the
naiad has an assistant whose job is to collect the letters that scroll
off  the  top  of  the  screen,  and  replace   them   in   the   box.
Unfortunately, not all programs scroll;  some just repaint the screen,
and the assistant naiad is unable to run around fast enough to salvage
all the letters.

One  of the most powerful nominal magics is in the BIOS;  the word IBM
is embedded in the best ones, a name that is synonymous with  computer
power.   Without  this  magic  word,  the  BIOS  is significantly less
powerful, and many programs will refuse  to  run.   The  AT  BIOS  has
IIBBMM  embedded;   this  is  obviously  twice as powerful, but is the
reason why the AT is not fully compatible with the PC and XT.

The keyboard is connected to the computed via a hollow  tube.   Inside
the  system  box there is an elf;  elves have very sharp ears, and the
elf's job is to listen very carefully down the tube to hear which keys
has  been  pressed.  Some programs (such as Superkey) replace this elf
with their own elf, but this can cause problems, as the  original  elf
can get angry, and the two elves fight.  While this is going on, there
is no-one listening to the keyboard, and the troll waits in  vain  for
further  requests.  Keybuk is the oldest elf-replacing program, and is
therefore the most  powerful.   The  Keybuk  elf  won't  tolerate  any
newcomers.

You've probably wondered why there are so many problems with printers.
Now that you understand how a computer works, the answer  is  obvious.
The  first problem is the cable, which is always black, as it works by
black magic.  Unless the spell on the  cable  is  exactly  right,  the
troll's  shouts cannot be heard at the printer end.  The other problem
is that the leprechaun in the printer is too far away from  the  troll
to  be  directly  affected  by  his  magic,  and so has a considerable
measure of independence.  Leprechauns are mischievous  creatures,  and
like  nothing  better  than to pay a good trick on the troll.  So they
mix up the characters that the troll shouts down the cable,  or  print
all kinds of crazy hieroglyphics.  Leprechauns also have a thing about
gold;  that's why so many of them refuse to print pound signs.

Leprechauns are just having fun;  they don't mean any harm.   But  the
demon  in  the  modem  is genuinely evil.  Modems are usually the most
distant thing that is part of your computer;  internal modems are made
the  same  way as external ones, so suffer from the same problems.  BT
have tried to do something  about  the  modem  problem  by  putting  a
blessing  on those that might behave properly.  But the white BT magic
soon wears off, and the dark side of  the  modem  demon  soon  asserts
itself.  Modems, as you will have guessed by now, work by the blackest
magic;  the only part of  the  computer  that  uses  the  wicked  art.
Modems  are  made  in special underground factories, protected against
leaks by containment pentagrams.  Only certified warlocks are  allowed
to  supervise  the  creation  process.   None  of  the  major computer
manufacturers allow the taint of the modem to besmirch  them,  and  no
reputable dealer will sell you one.

To  get  a  modem,  you  have to undergo a special ritual known as the
RS232, so complex and arcane that its innermost secrets are  known  to
only three men.  You have to learn the modem magic words, like V22bis,
and DTE.  As a final precaution you are required to know how to  cross
a  cable  (should  the  demon escape, you will need a crossed cable to
nullify him).  Only then will you be admitted to the secret  world  of
comms.

Getting  a BT-blessed modem isn't the end of it, though.  You now have
to connect the modem to the telephone, and consult  a  book  of  magic
words.   These  words  come  in  three  classes;  number, identity and
riddle-answer.  The first one is an wish  to  BT  to  connect  you  to
another  computer.   BT  is run by fairies, and sometimes the fairy at
your local exchange will grant the wish, although sometimes she won't.
The  wish  might  be  refused because the lion is busy, or because you
have asked for the wrong lion, or for many other reasons.  But if  you
are  lucky, the lion will be available, and the BT fairy will feed you
into it.  Now you must do something incredibly  dangerous;   you  must
give  your name to a demon that you haven't even met.  The demon might
simply sneer at your name, and refuse to acknowledge your existence  -
it might even change your name to something completely unintelligible.
If this happens, drop the lion immediately, as  if  the  influence  of
this nominal magic were to affect you, it could make you very ill.  If
the demon is in a good mood, though, it will let you talk to the troll
on  the  remote  computer.   The  troll  will immediately ask a riddle
before letting you in, but if you get it right within  three  guesses,
he will let you ask him questions.

But  while you are talking to the remote troll, the lion will probably
start making noises, as the BT fairies don't  feed  it  enough.   This
noise can be so bad that the remote troll can't hear you properly, and
you'll have to start all over again.

This is why data communications are so uncertain;  there are  so  many
incompatible  entities that need to co-operate to make the thing work.
The two trolls can only talk to each other by  way  of  the  two  evil
demons,  connected  by  the  good fairies at BT with a noisy lion.  We
should have stuck to tin cans and string.