| 摘要 |
<p>PURPOSE:To reduce the loss with respect to time by storing the state of a device in a non-volatile storage means before the processing of the device is stopped when a supply voltage falls and discriminating the state of the device in accordance with stored contents when power is restored. CONSTITUTION:A computer system as an information processor consists of a CPU 11, a memory 12 for data processing, a keyboard 16, etc., and is provided with a reset circuit 13, a non-volatile RAM 14, a clock 19, etc. If the supply voltage falls because of power failure (an interrupt signal is supplied from the reset circuit 13), the CPU 11 reads the current time from the clock 19 and stored it in the RAM 14 as the state of the processor. The CPU 11 stores the time of voltage restoration similarly. Both times are compared with each other to calculate a power failure time, and this time is compared with a preliminarily stored reference time to discriminate conditions of the processor. If the power failure time is short, a self-diagnostic system is not executed to start the system.</p> |
