z80:Opcodes:XOR

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XOR is an instruction that takes one 8-bit input and compares it with the accumulator. XOR is similar to Or, except for one thing: only 1 of the 2 test bits can be set or else it will result in a zero. The final answer is stored to the accumulator.

0 and 0 result: 0
0 and 1 result: 1
1 and 0 result: 1
1 and 1 result: 0

Syntax

   XOR op8

Acceptable inputs

   xor a
   xor b
   xor c
   xor d
   xor e
   xor h
   xor l
   xor ixh
   xor ixl
   xor iyh
   xor iyl
   xor (hl)
   xor (ix+n)
   xor (iy+n)
   xor n		;8 bit constant

Effects

C and N flags cleared. P/V is parity, and rest are modified by definition.

Uses

XORing numbers is used a lot to invert sprites and such. It is also very useful in bit-masking. See here for more information about bit-masking.

T-States

r denotes 8-bit register.

r 4
X 7
(hl) 7
(ix+X) 19
(iy+X) 19

See Also

AND,BIT,CCF,CPL,OR,RES,SCF,SET