An instruction set is a list of all the instructions, with all their variations, that a processor can execute.
- Arithmetic such as add and subtract
- Logic instructions such as and, or, and not
- Data instructions such as move, input, output, load, and store
- Control flow instructions such as goto, if ... goto, call, and return.
An instruction set, or instruction set architecture (ISA), is the part of the computer architecture related to programming—including the native data types, instructions, registers, addressing modes, memory architecture, interrupt and exception handling—and external I/O. An ISA includes a specification of the set of opcodes (machine language), the native commands implemented by a particular central processing unit design.
Instruction set architecture is distinguished from microarchitecture, which is the detailed description of the system that is enough for completely describing the operation of all parts of the computing system, as well as how they are inter-connected and inter-operate to implement the ISA.
Computers with different microarchitectures can share a common instruction set. For example, the Intel Pentium and the AMD Athlon implement nearly identical versions of the x86 instruction set, but they are very different in internal designs.
Related pages[change | change source]
- digital signal processor
- graphics processing unit
- central processing unit
- Computer architecture
Other websites[change | change source]
- Mark Smotherman's Historical Computer Designs Page
- Microprocessor Instruction Set Cards
- A Set of Standard Microprocessor Programming Cards by Jonathan Bowen
- Randy Hyde's discussion on ISA