MICROPROCESSOR

PROBLEM TO BE SOLVED: To solve the problem that a maximum operation frequency to be regulated by instruction decoding and instruction execution, etc., is restricted when using the same microprocessor according to application. SOLUTION: The microprocessor invalidates a part of an instruction or an instruction set in order to vary the maximum operation frequency according to application, for example. As one example, the microprocessor includes an instruction fetching part for reading and fetching an instruction from a memory, an instruction decoding part for performing decoding processing with respect to the instruction fetched by the instruction fetching part, and an instruction execution part for executing the processing with respect to the decoded instruction. The instruction decoding part adopts an external setting value as an input to exclude a part of the instructions from decoding targets or reduce the speed through the use of the external setting value. COPYRIGHT: (C)2011,JPO&INPIT