Status Register and Boolean Formula

I	T	H	S	V	N	Z	C
–	–	–	⇔	⇔	⇔	⇔	–

S

N ⊕ V, for signed tests.

V

R7 • R6 • R5 • R4 • R3 • R2 • R1 • R0

Set if two’s complement overflow resulted from the operation; cleared otherwise. Two’s complement overflow occurs if and only if Rd was $7F before the operation.

N

Set if MSB of the result is set; cleared otherwise.

Z

R7 • R6 • R5 • R4 • R3 • R2 • R1 • R0

Set if the result is $00; cleared otherwise.

R (Result) equals Rd after the operation.

Example:

 clr r22 ; clear r22
loop: inc r22 ; increment r22
 ...
 cpi r22,$4F ; Compare r22 to $4f
 brne loop ; Branch if not equal
 nop ; Continue (do nothing)

Words: 1 (2 bytes)
Cycles: 1