| 摘要 |
PURPOSE:To change the machine clock of a device to be diagnosed even in an on-line mode and to attain the diagnosis of said device, by changing the data processing cycle of the device to be diagnosed in order to secure the nor mal working inside an information processor. CONSTITUTION:In a diagnosis mode only the clock of the 2nd arithmetic unit 103 to be diagnosed is set at a low speed. While a storage device 101 and an arithmetic unit 102 are actuated by the original machine clocks. Thus a clock selection indicating circuit 106 gives indications t a clock selection circuit 107 and a data processing cycle control circuit 105 so that the unit 103 works on the 2nd machine clock set at a lower speed than the original machine clock. As a result, the circuit 107 selects the 2nd machine clock and supplies it to the unit 103 via a clock signal line 122. |
