Intel 8253 - Page 529

4/17/98 6-129 Addressing Modes and Data Types
NEG Negate
Syntax: NEG Rd
Operation: Rd <-- (
Rd) + 1
Description: The destination register is negated (twos complement). The destination may be a byte
or a word.
Size: Byte, Word
Flags Updated: V, N, Z
The V flag is set if a twos complement overflow occurred: the original value = result = 8000 hex
for a word operation or 80 hex for a byte operation.
Bytes: 2
Clocks: 3
Encoding:
1 0 0 1 SZ 0 0 0
d d d d 1 0 1 1