| 摘要 |
PURPOSE:To effectively prevent the wrong use of software programs by providing a pattern generating circuit which gives preliminarily set pattern data to a port of a program executing device at a preliminarily set period. CONSTITUTION:The pattern generating circuit which gives preliminarily set pattern data to the port of the program executing device at a preliminarily set period is provided correspondingly to a program. In case the period on the outside of an allowable range is detected, an error counter is incremented, and the period of pattern data is checked repeatedly while deciding whether the error number reaches 3 or not; and if three or more errors are detected, it is decided that this pattern data is not pattern data obtained from the pattern generating circuit 3, and the execution of a program 2 is stopped. |
