# Any gate i can substitute to xor gate?

1. Jan 15, 2009

### chrisalviola

any gate i can substitute to xor gate?
if i dont have xor gate what gate i can use to substitute it?

2. Jan 15, 2009

### mgb_phys

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.

3. Jan 15, 2009

### rootX

define xor with a truth table.

4. Jan 15, 2009

### chrisalviola

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

5. Jan 15, 2009

### chrisalviola

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

6. Jan 15, 2009

### rootX

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...)

7. Jan 15, 2009

### chrisalviola

problem solved

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

Last edited by a moderator: May 3, 2017
8. Jan 15, 2009

### chrisalviola

tnks

9. Jan 15, 2009

### mgb_phys

Isn't it, A or B and not( A and B)