R
Radium
Okay, however, I don't see any advantage to converting electric[.....]
3. Magnetic parts
Why would you care if it is magnetic? Non-linear magneto-optical
effects could allow very fast logic at extremely low power levels.
Eventually the signal has to become electric for processing. Why waste
time converting signals from electric to magnetic [and visa versa]?
I think you missed the point. The signals start out as keystrokes and
mouse clicks and end up as dots on a CRT. We only make them into
electronic signals because we have a very easy way to process
electronic signals. There is no reason to not convert them to light
or magnetic fields if that provides a way to process them very quickly
at low power levels.
[.....]
signals to magnetic signals. Optical, maybe or maybe not, depending on
the application. But definitely not magnetic.
You have ruled out magnetics without having explored everything it may
bring you. You need to imagine the PC you really want and not how it
is done.
What are the advantages of magnetics vs. electrics?
Think of a box with a monitor and keyboard etc plugged into it. You
can't see into the box all you know is that it does everything you
neede it to do, there are no moving parts, it draws very little power
and will have a life over 100 years.
Okay.
If this is the PC you want, why are you setting limits on whats inside
it beyond that?
It's a matter of personal preference.
A PC with the mathematically low amount of ROM would by its nature be
slow.
Why?
I'm sure you have "zipped" and "unzipped" files. The process
of unzipping is converting a lower number of bits into a larger number
that are easier to deal with in software. It takes a while to do this
process. This extra time is what you would be adding to your PC.
[....]
I don't use zip, unless I really need to. So far, I've never had to.
Winzip is a pain in the @$$.
No, it contains one. The buttons and stuff are there too and they
aren't ROM.
Is the ROM built into the keyboard?
MooseFET wrote:
Radium, perhaps this simplified example of a keyboard will help you to
think through what you are talking about.
Okay.
Let's look at the requirements. You have about 100 switches (keys) and
when each one is pressed, you want to output a specific 8 bit pattern
(the ASCII code for the key). The logic for this is pretty simple to
synthesize. You have 100 circuits, each similar to each other but
slightly different. Each one, when corresponding the switch is pressed
enables a pattern of logical highs and lows to the output bus. This
will work, but now you have 100 separate circuits. If each circuit was
one one chip, it would take 100 chips. OK, no one would do that - you
certainly would combine them. But now you have a chip with 100 inputs
and pins are expensive. So let's say we arrange the switches in a 10 by
10 matrix so that what is output when a switch is pressed is the row and
column of the matrix corresponding to that switch. So now you have 20
inputs. But with an other simple circuit you can use a 4 bit value to
indicate which of the 10 rows the pressed key belongs to. Similarly for
the column. Now we are down to 8 bits. These can be fed into a chip
that decodes these 8 inputs (again, easy to synthesize) into one of 100
lines. These in turn select one of 100 patterns of logic highs and lows
to output.
Interesting. In '90, I had a green monochrome Corona PC. Its keyboard
did not connect to the PC via pins but rather through a cord
resembling a telephone cord. The plugs on both ends resembled that
used for telephones.
This chip, the one that takes the 8 inputs (AKA address) and
outputs a particular pattern (AKA data) *is* a ROM.
What are the alternatives to ROM?
There is nothing
inherently wrong with ROM, it is just a more convenient and lower cost
way to do what you could otherwise do with discrete logic.
I am aware that there is nothing objectively wrong with ROM. However,
as a matter of personal preference, I would like other alternatives.
It's like preferring garlic over onions [or visa versa].