orthogonal instruction set
<architecture> An {instruction set} where all (or most)
instructions have the same format and all {registers} and
{addressing modes} can be used interchangeably - the choices
of {op code}, register, and addressing mode are mutually
independent (loosely speaking, the choices are
"{orthogonal}"). This contrasts with some early {Intel}
{microprocessors} where only certain registers could be used
by certain instructions.
Examples include the {PDP-11}, {680x0}, {ARM}, {VAX}.
(2002-06-26)