| 摘要 |
A person who would like to cancel read-protection of ROM data inputs an "address," an "information length," and an "input information part." The input information part should be a part of a data file stored in the ROM. The input address corresponds to the starting address of the information part in the ROM. The input information length is the length of the input information part. A ROM-data read-control circuit reads a stored information part with the input information length from an area or areas in the ROM with the input starting address. Next, the ROM-data read-control circuit compares the stored information part with the input information part. The ROM-data read-control circuit cancels the read-protection when the input information part coincides with the stored information part.
|
