摘要 |
PURPOSE:To prevent the contents of a stack from being varied, by constituting the titled system so that the stack can be checked by a step unit of a program. CONSTITUTION:By utilizing an interruption outputted to a CPU 4 from an interruption generating device 21, when a program is executed by a single step, it is allowed to branch to a subroutine for executing a stack check, whenever the execution ends one step. In such a way, by executing the program by a single step mode, an interruption is generated, whenever the execution of one step is ended and the stack check is executed, and a place of the program in which the stack has been broken down can be detected by a step unit. |