Motorola 68000

41
The 68000's Instruction Set
Destination operand addressing modes
NEGX Negate with extend
Operation: [destination] ← 0 - [destination] - [X]
Syntax: NEGX <ea>
Attributes: Size = byte, word, longword
Description: The operand addressed as the destination and the extend bit are
subtracted from zero. NEGX is the same as NEG except that the X-
bit is also subtracted from zero.
Condition codes: X N Z V C
* * * * *
The Z-bit is cleared if the result is non-zero and is unchanged
otherwise. The X-bit is set to the same value as the C-bit.
Destination operand addressing modes
NOP No operation
Operation: None
Syntax: NOP
Attributes: Unsized
Description: The no operation instruction, NOP performs no computation.
Execution continues with the instruction following the NOP
instruction. The processor's state is not modified by a NOP.