| 摘要 |
PURPOSE: To provide a device in which a circuit performing read-out of a ROM is separated from the other circuit to determine which circuit has caused defect, or defective read-out of a ROM caused by drop of power source voltage is prevented, when defect is caused in operation of a device. CONSTITUTION: The device is controlled so that when voltage of a low level is applied to an input pad PD11 and the voltage reaches a power-on detection level after applying a power source as usual, a start pulse is inputted to a ROM read-out control circuit RRC through a pulse generating circuit PG11 and a NOR circuit NR11, and read-out of a ROM is performed. However, when voltage PRDIS of high level is inputted to the input pad PD11, a start pulse is not outputted from the NOR circuit NR11, read-out of a ROM is not started automatically after applying a power source. Thereby, automatic start of read- out of a ROM is stopped at the time of occurrence of defect, and it can be determined whether a defect part exists in a read-out part of the ROM or in the other part depending on whether defect is caused or not.
|
