VIRTUAL CPU FLAG FORMING DEVICE

摘要

PURPOSE:To easily make one circuit corresond to various objective CPUs and to sharply simplify the circuit by connverting logics to be rearranged to farmwares. CONSTITUTION:A 4-input multiplexer 2 on a prescribed position coincident with a flag meaned by a vitual CPU flag E based on a 4-input multiplexer selecting signal B and an output from an n1 input multiplexer 1 is selected out of four inputs. One flag selected out of objective CPU flags D is outputted from the 4-input multiplexer 2 on the prescribed position and the result is latched in a latch circuit 3 based on latch clock signal C. All the flags D of the objective CPU are rearranged into the flags E of the virtual CPU by repeating said operation by the number n1 of flags D of the objective CPU. Consequently, the device can be allowed to correspond to various objective CPUs and the circuit can be simplified.