http://www.mikroe.com/chapters/view/10/chapter-9-instruction-set/

XORWF Exclusive OR W with f​

Syntax: [​

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label ] XORWF f,d
Operands: 0  f  127
d  [0,1]
Operation: (W) .XOR. (f) destination)
Status Affected: Z
Description: Exclusive OR the contents of the W
register with register ‘f’. If ‘d’ is ‘0’, the
result is stored in the W register. If ‘d’​

is ‘1’, the result is


What does status affected, z, mean?

 

It means that the zero flag in the status register will be affected by using this operation... if the result of the operation its zero, the status flag is set.

 

It also means that the other bits in STATUS (C and DC) are not affected which sometimes comes in handy in writing shorter code. You can do an instruction which affects C, then XOR, then test the C bit which is still valid.