資料來源 : WordNet®
operation code
n : the portion of a set of operation descriptions that
specifies the operation to be performed; the set of
operations in a computer [syn: {order code}]
資料來源 : Free On-Line Dictionary of Computing
operation code
(Or "op code") The part or parts of a {machine
language} instruction which determines what kind of action the
computer should take, e.g. add, jump, load, store. In any
particular {instruction set} certain fixed bit positions
within the instruction word contain the op code, others give
{parameters} such as the addresses or {registers} involved.
For example, in a 32-bit instruction the most significant
eight bits might be the op code giving 256 possible
operations.
For some instruction sets, certain values in the fixed bit
positions may select a group of operations and the exact
operation may depend on other bits within instruction word or
subsequent words.
When programming in {assembly language}, the op code is
represented by a readable name called an {instruction
mnemonic}.
(1997-02-14)