| 摘要 |
PURPOSE:To prevent a system from stopping operating unnecessarily even if a power failure occurs during write operation, by avoiding error occurrence at the time of reading. CONSTITUTION:Power-failure detection circuit 1 detects a power failure, if occurring to an AC power supply while write data are being written from a memory to a write method, and data control circuit 2 mades write data after the power failure into a specific pattern and the write them to the write method. After the write data made into the specific pattern are transferred to the end part of a sector, stop circuit 5 stops the write operation forcibly. As a result, when the write data are read out after the power supply recovers, data for one sector, even if incorrect, are not regarded as an error because of no absence of data during the write operation. |
