[destination] ← 0 - [destination]
NEG <ea>Size byte, word, longword
Subtract the destination operand from 0 and store the result in the destination location. The difference between NOT and NEG instructions is that NOT performs a bit-by-bit logical complementation, while a NEG performs a two's complement arithmetic subtraction. All bits of the condition code register are modified by a NEG operation. For example, if D3.B = 111001112, the logical operation NEG.B D3 results in D3 = 000110012 (XNZVC=10001) and NOT.B D3= 000110002 (XNZVC=-0000).
| X | N | Z | V | C |
|---|---|---|---|---|
| * | * | * | * | * |
Note that the X-bit is set to the value of the C-bit.
| Dn | An | (An) | (An)+ | ‑(An) | (d,An) | (d,An,Xi) | ABS.W | ABS.L | (d,PC) | (d,PC,Xn) | imm |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
From MOTOROLA M68000 FAMILY Programmer's reference manual. Copyright 1992 by Motorola Inc./NXP. Adapted with permission.