| 摘要 |
PURPOSE:To enable an user to execute the clock margin test of a self-device simply by starting a testing means at the initialization of the self-device. CONSTITUTION:Registers 4, 7 are connected to an initializing signal generating circuit 6 and constituted so as not to be initialized by an initializing signal generated from an initializing signal generating circuit 5. The oscillation frequency of an oscillator 1 is set up to a reference clock signal frequency of an information processor, the oscillation frequency of an oscillator 2 is set up to a proper value higher than that of the oscillator 1 and near the operating limit of the information processor, and when the registers 4, 7 are initialized by an initializing signal outputted from the circuit 6, a signal from the oscillator 1 is selected by a selecting circuit and outputted to a clock signal line 20. Since the starting of the clock margin test is included in a diagnosis program, the test can be easily operated without specific knowledge. |
