Help:Explain multiplexers...

Not sure where Multiplexers are used in CS (that is, software). Multiplexers are a hardware component.

Simple example: You have 4 wires running to a multiplexer, labelled A - D, then you have 2 wires on another part of the chip labelled 1 and 2.

Basically, you take the value of 1 and 2(that is, if they are asserted or not) in binary (00, 01, 10, 11), then use that to determine what is output form the chip (A=00, B=01, C=10, D=11)

That''s what a multiplexer does.

It''s kind of like telephone operator/switching station. It has a number of data inputs, and then you can select (with the adressing pins) which one of the inputs that "passes through" the chip to the output pins...
I don''t really know any applications... When I studied digital electronics we just built silly excercises... not looking at the Real World^(tm) how the stuff is used...
A friend of mine used multiplexers when he had to make complex logic functions of the sort f(a,b,c) (three boolean inputs, one output). He connected the data inputs of the chip to either ground or VCC and the inputs/variables to the adress pins, letting him set what each of 2³ input states would yield as output (hmmm... hope you understand that...)
Yay! I''m graduating now
... And then there those who have hundreds of days left (sounds better in Swedish )
/Ksero

Thanks dudes.

I called a friend and he also gave me the "telephone switchboard" (KSero) version.

I am still amazed how the author''s of a book such as " *Foundations* of CS" can succed in making *every-little-thing* seem strange and complicated. When in fact..it (most of the time) is rather simple.

I''d take a "hackerish" text-file over any "course litterature" anyday.

/Ekas78

Hey KSero btw, What school were you at?

/Ekas

I live in Västerås, studying at the ABB Industrigymnasium... It''s a science/engineering education (like the Swedish "naturteknisk"). We study a lot of mechanics and electricity (I''m sick of it ... It was interesting at first, reaching a peak with analog & digital electronics. When we started getting into three-phase, motors and transformers... it was just too much...)
We have almost all the courses that the scientific program has, except stuff like biology and history... It''s a great school... A bit hard to become admitted (is that correct?), but almost all the students have a strong motivation to study... It''s a small school, 150 students total, which means that you develop a closer relationship with cyour teachers... They''re available most of the time if you''ve got questions or ponderings... I sound like an advertising catalogue, don''t I? Oh well... It''s been 3 fantastic years...

About course literature vs. hackerish text files. I agree, if the book is sufficiently advanced you need to have a certain basic knowledge to be able to read it. Professors can really help here by holding seminars/presenting the material in a perspicuous way.

BTW, a really great program for building circuits with logic gates, chips (they support a *lot* of different chips - among them several multiplexers) and electrical components is Electronics Workbench (the newer versions are called multisim)

/Ksero

Electronic workbench is good for making real schemes, but if u want just want to create model like - !x!y + xy + ... It is quite annoying to put wires all together

I used something like Crocodile for it, but I forgot name If someone knows some simple programm & could post a link...

Lekha

KSero Btw, Congrats!. Free beer for everybody? I''m at the university of Vaxjo..so do you mind if i bring a couple of 100 "de-partied"(Need more partying) friends? :-)