| 摘要 |
PURPOSE:To detect an operation due to the illegal remodeling of a program, and to inhibit following operations. CONSTITUTION:A gate circuit is provided on an address/data bus connecting a CPU to an operating system program(OS) ROW and an application program (application) ROM, the gate circuit is opened only by processings (steps S21-S25) according to an initialization software program, and a program processing according to the contents of the OSROM and the application ROM is activated (steps S28 and S34). Then, at the time of abnormality detection (step S35), the gate circuit is closed (step S33). |
