Patent attributes
A microcontroller includes a memory, direct memory access (DMA) controllers and a microprocessor. The microprocessor maintains one or more memory protection (MP) configurations to control access to protected memory areas of the microcontroller. In response to a secure service call of an unsecure user-application, the microprocessor executes a state machine which disables interrupt requests, determining whether DMA controller configurations and MP configurations satisfy secure-service criteria. When the secure-service criteria are satisfied, at least one secure operation associated with the secure service call is performed, and memory areas accessed during the execution of the at least one secure operation are cleaned. The interrupt requests are re-enabled and a response to the secure service call is generated.