How to construct XOR function using NORs?

The last two months of Embedded Systems Programming

has a nice column on Karnaugh maps and the Quien-McClusky method -- look for Jack Crenshaw's math column.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Work out how to make other stuff. Start out with an inverter. Now, see if you can use this to make an and gate.

Now, go on to nand and ...

Now, you have the building blocks. Start playing with them, and see how you can reduce the gate count as much as possible.

EXOR(A,B)=OR(AND(A,/B),AND(/A,B)) and since AND(X,Y)=NOR(/X,/Y) and OR(X,Y)=NOT NOR(X,Y) you're done.

-------------------- These files comprise a complete course in Boolean transformations. If you study them you can do anything.

ftp://ftp.armory.com/pub/user/rstevew/TUTS/ files: boolean & boolean2 and demorgan & demorgan2 -> .txt

or:

and add an inverter to the output.

-Steve

--
-Steve Walz  rstevew@armory.com   ftp://ftp.armory.com/pub/user/rstevew
Electronics Site!! 1000's of Files and Dirs!!  With Schematics Galore!!
http://www.armory.com/~rstevew or http://www.armory.com/~rstevew/Public

On Sunday 26 September 2004 02:12 pm, Geir Klemetsen did deign to grace us with the following:

Please don't do the kiddies' homework for them.

Thanks, Rich

"Rakesh Sharma" skrev i melding news: snipped-for-privacy@posting.google.com...

This should work:

__ .------------|>=| | |1 |o-------. | .-|__| | | __ | | __ __ A----o-|>=| | '-|>=| .------|>=| |1 |o----| |1 |o-' |1 |o- X B----o-|__| | .-|__| .---|__| | | __ | | | '-|>=| | | | |1 |o-------' 0| o------------|__| created by Andy´s ASCII-Circuit v1.24.140803 Beta

Must be viewed in fixed font.

I've deliberately taken out the cross-posting.

You do realize that this sort of question is in all kinds of books. If you don't have a source to look it up, you do lack a basic library that everyone interested in electronics should have.

One could go to the public library if one's stuck for lack of books.

Likely a search of websites will turn it up.

Finally, the only real reason you would want to do this is for homework. It's much simpler to get an exclusive-or gate than wire up other gates. Michael

Why's everyone got such a downer on helping kids with homework? Sure, don't do it for them, but a prod in the right direction is reasonable.

In my day we'd have got extra marks for knowing where to look for help on the Internet!

Andyb

-- The above email address is whitelisted. If I don't have your address already, I wont see your message.

All of the propositional functions can be expressed in terms of 'nor', (or in terms of 'nand')

If 'nor' is primitive:

1. not(p) =df (p nor p) 2. (p or q) =df not(p nor q) 3. (p and q) =df not(not(p) or not(q)) 4. (p nand q) =df not(p and q) 5. (p only if q) =df (not(p) or q) 6. (p if q) =df (p or not(q)) 7. (p if and only if q) =df (p if q) and (p only if q) 8. (p xor q) =df not(p if and only if q).

1a. ~p (p nor p) 2a. (p v q) ~(p nor q) 3a. (p & q) ~(~p v ~q) 4a. (p nand q) ~(p & q) 5a. (p -> q) (~p v q) 6a. (p