| 摘要 |
PURPOSE:To obtain stable data by storing output signals of a reference logical circuit and a logical circuit to be diagnosed at the same timing, and providing a selecting circuit which switshes a comparing circuit and a processing part. CONSTITUTION:Output signals of the reference logical circuit 2 and logical circuit 1 to be measured are inputted to receiver circuits 3 and 4; the output signal (a) of the circuit 4 is inputted to a memory circuit 6 and a selecting circuit 11 and the output signal (e) of the circuit 3 is inputted to the circuit 11. When the signal (a) is inputted, the circuit 6 is stored at the timing (f) of a clock dividing circuit 8. A selection signal S operates for mode switching to select the data input (a) and selects (g) as a trigger input. At this time, a memory circuit 5 obtains an output signal (b). The signals (b) and (c) are compared 7 with each other to output a comparison result signal (d) to the processing part9. Then when the data input (a) changes in polarity between the signals (f) and (g), the signals (b) and (c) from the circuits 5 and 6 become dissident and (d) is inputted as a dissidence signal to the processing part 9, thereby stoppingdiagnosing operation. |
