Method for monitoring microprocessor systems and stored-program controls

摘要

In this method, a control unit (1) is directly connected to the system bus of the microprocessor system (20) or of the stored-program control. The control unit compares checkpoints inserted in the safety-relevant area in the program paths with a stored map and outputs an error signal in the case of deviations. The control-unit (1) hardware construction differs from that of the central processing unit, which also operates with a different program. The checkpoints are determined by coordinates or other numbering and must be accurately defined by the control unit (1) by means of following information: a) identification of all checkpoints which follow the current checkpoint; b) the maximum time which may elapse until the next checkpoint is reached. The control unit compares this identification with the stored permissible identification and responds in the case of deviations.