| 摘要 |
PURPOSE:To facilitate the check of an asynchronous signal processing function of a data processing unit by inputting an asynchronous signal from a signal generating circuit oscillated by a start from the host device. CONSTITUTION:A main microprocessor unit (MPU) 5 designates a mode register 3a to the test mode and an output signal of a pseudo signal register 2a is selected as an asynchronous signal. Moreover, the MPU 5 issues an input/output command to the input/output control section 8a, a main control section 12 controls the data input/output section 13 to apply the input/output operation with the input/output device 9a. Moreover, the MPU 5 turns on/off a prescribed bit of the pseudo signal register 2a at an optional timing in such a state. Thus, the MPU 5 turns on/off the bit of the pseudo signal register 2a independently of the operation of the input/output control section 8a to generate the asynchro nous signal in the optional timing. Thus, the operation of the input/output con trol section 8a in every timing of the asynchronous signal to check the device surely. |
