Motorola 68000 - Page 44

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The 68000's Instruction Set
Application: NOPs can be used to introduce a delay in code. Some programmers
use them to provide space for patches  two or more NOPs can
later be replaced by branch or jump instructions to fix a bug. This
use of the NOP is seriously frowned upon, as errors should be
corrected by re-assembling the code rather than by patching it.
Condition codes: X N Z V C
- - - - -
NOT Logical complement
Operation: [destination] ← [destination]
Syntax: NOT <ea>
Attributes: Size = byte, word, longword
Description: Calculate the logical complement of the destination and store the
result in the destination. The difference between NOT and NEG is
that NOT performs a bit-by-bit logical complementation, while a
NEG performs a twos complement arithmetic subtraction. More-
over, NEG updates all bits of the CCR, while NOT clears the V- and
C-bits, updates the N- and Z-bits, and doesn't affect the X-bit.
Condition codes: X N Z V C
- * * 0 0
Source operand addressing modes
OR OR logical
Operation: [destination] ← [source] + [destination]
Syntax: OR <ea>,Dn
OR Dn,<ea>
Attributes: Size = byte, word, longword