instruction set architecture

architecture (ISA) The parts of a processor's design that

need to be understood in order to write assembly language,

such as the machine language instructions and registers.

Parts of the architecture that are left to the implementation,

such as number of superscalar functional units, cache

size and cycle speed, are not part of the ISA.

The definition of SPARC, for example, carefully

distinguishes between an implementation and a specification.

(1999-01-16)