orthogonal instruction set

An {instruction set} where all (or most) instructions have the

same format and all register can be used interchangeably - the

choice of which register to use is orthogonal to the choice of

instruction. This contrasts with some early {Intel}

{microprocessor}s where only certain registers could be used

by certain instructions.

Examples include the {PDP-11}, {680x0}, {ARM}, {VAX}.

(1995-01-05)