Or, Xor, & And command tutorial

**-LeetGamer-** · 06-17-2010, 12:29 AM

Tutorial by TheEliteOne aka -LeetGamer-
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Commands: Or, Xor, And

First you need to know what Binary is. Binary is another form of counting, like normal numbers (Decimal), and hex numbers (Hexadecimal). But Binary only can use 0 and 1. This is needed to learn these commands, now here is a decimal (Normal number) to Binary converter:

Code:

http://acc6.its.brooklyn.cuny.edu/~gurwitz/core5/nav2tool.html

First what the command does is converts the hex value into Binary. So if we had 8 and 2 in hex here will be are binary values:

1000 (This is 8)
10 (This is 2)

Now we need them to be equal, so we add zeros:

1000 (This is 8)
0010 (This is 2)

Now they are equal size. These two binary numbers are what I will be using for all three commands. When I say each set, I mean that the first set is 1 and 0, the second is 0 and 0, the third is 0 and 1, and the last is 0 and 0. Basically each diget in the Binary number.

Or:
Or

1000
0010

In each set, the result is 1 if the top diget is one OR the bottom diget is one OR both digets are one, if none of those are true the result is zero.

1000
0010
------
1010 (This is are result, in decimal it is 10 and in hex it is A)

So 8 || 2 = 10 and in hex: 0x8 || 0x2 = 0xA. The symbol for Or is two of these: ||

Xor:
Exclusive Or

1000
0010

In each set, the result is 1 if the two digets are different, and the result is 0 if they are the same.

1000
0010
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1010 (This is are result, same as last time, but do not think that Or and Xor do the same thing!)

So 8 ^^ 2 = 10 and in hex: 0x8 ^^ 0x2 = 0xA. The symbol for Xor is two of these: ^^

And:
And

1000
0010

In each set, the result is 1 if the first AND the second diget are 1, if that is not true the result is 0.

1000
0010
------
0000 (This is are answer, in dec and hex it is zero)

So 8 && 2 = 0 and in hex: 0x8 && 0x2 = 0x0. The symbol for And is two of these: &&

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Ori, Xori, & Andi are the same thing, but they take a immediate value that you give and a register, and not two register contents.

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