The attributes of a digital computer as seen by a
machine (assembly) language programmer. ISA
includes the processor and input/output
instruction sets, their formats, operation codes,
and addressing modes; memory management and
partitioning if accessible to the machine language
programmer; the speed of accessible clocks;
interrupt structure; and the manner of use and
format of all registers and memory locations that
may be directly manipulated or tested by a machine language program. This definition
excludes the time or speed of any operation,
internal computer partitioning, electrical and
physical organization, circuits and components
of the computer, manufacturing technology,
memory organization, memory cycle time, and
memory bus widths.