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Bitc – Samsung S3F80JB User Manual

Page 147

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S3F80JB

INSTRUCTION SET

6-19

BITC

Bit Complement

BITC

dst.b

Operation: dst(b)

← NOT dst(b)

This instruction complements the specified bit within the destination without affecting any other
bits in the destination.

Flags: C:

Unaffected.

Z: Set if the result is "0"; cleared otherwise.

S: Cleared to "0".

V: Undefined.

D: Unaffected.

H: Unaffected.

Format:

Bytes Cycles Opcode

(Hex)

Addr Mode

dst

opc

dst | b | 0

2 4 57

rb

NOTE: In the second byte of the instruction format, the destination address is four bits, the bit address 'b'

is three bits, and the LSB address value is one bit in length.

Example:

Given: R1 = 07H

BITC R1.1

R1 = 05H

If working register R1 contains the value 07H (00000111B), the statement "BITC R1.1"
complements bit one of the destination and leaves the value 05H (00000101B) in register R1.
Because the result of the complement is not "0", the zero flag (Z) in the FLAGS register (0D5H) is
cleared.