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chrisalviola
Jan15-09, 10:31 PM
any gate i can substitute to xor gate?
if i dont have xor gate what gate i can use to substitute it?

mgb_phys
Jan15-09, 10:33 PM
If this is homework - what is XOR in boolean algebra ?

In practical terms you can build any logic out of either NAND or NOR, most chips only implement one of these.

rootX
Jan15-09, 10:34 PM
any gate i can substitute to xor gate?
if i dont have xor gate what gate i can use to substitute it?

define xor with a truth table.

chrisalviola
Jan15-09, 10:38 PM
If this is homework - what is XOR in boolean algebra ?

In practical terms you can build any logic out of either NAND or NOR, most chips only implement one of these.

nope not a homework
i want to make a binary adder cuircuit i dont have an xor gate only and, or & not.

chrisalviola
Jan15-09, 10:39 PM
define xor with a truth table.

0 0 -0
0 1-1
1 0-1
1 1-0

rootX
Jan15-09, 10:45 PM
0 0 -0
0 1-1
1 0-1
1 1-0

xor = not(a).b + a.not(b)

I also thought this is a homework problem. You can easily get this into and/or gates. If there are more than 2 inputs, you should be using k-maps. Once, you have in and/or gates, it is simple to convert it into nand (using Sum of products form) or nors (using products of sums or simply messing with bool algebra...)

chrisalviola
Jan15-09, 10:50 PM
problem solved

http://www.play-hookey.com/digital/xor_function.html

chrisalviola
Jan15-09, 10:51 PM
xor = not(a).b + a.not(b)

I also thought this is a homework problem. You can easily get this into and/or gates. If there are more than 2 inputs, you should be using k-maps. Once, you have in and/or gates, it is simple to convert it into nand (using Sum of products form) or nors (using products of sums or simply messing with bool algebra...)
tnks

mgb_phys
Jan15-09, 10:54 PM
Isn't it, A or B and not( A and B)