Patent ID: 6807595
Filing Date: 2004-10-19
Classification: G06F,Y02D

Abstract:
A system for use in a mobile communications device, said system comprising:a microprocessor having components for responding to interrupt requests by interrupting current processing and performing an interrupt service routine associated with the interrupt request; peripheral processing units having components for generating interrupt requests for sending to the microprocessor; and . an interrupt controller having components for receiving interrupt requests directed to the microprocessor from the peripheral processing units and for prioritizing the interrupt requests on behalf of the microprocessor, wherein said interrupt controller includes: an interrupt source interface unit for receiving interrupt requests directed to the microprocessor from the peripheral processing units; an interrupt prioritization unit for identifying an interrupt request of highest priority from among the interrupt requests received; and a microprocessor notification unit for notifying the microprocessor of the interrupt request of highest priority, wherein said microprocessor notification unit includes: an interrupt staging unit for storing a value representative of the interrupt request of highest priority; and an interrupt transmission unit for transmitting a notification signal the microprocessor indicating that a new interrupt request is stored in the interrupt storage means, and wherein the microprocessor includes: an interrupt notification signal reception unit; interrupt access unit for reading the value representative of the new interrupt request stored within the interrupt staging unit; a context storage unit for saving a current context of the microprocessor; an interrupt stack controller for determining whether a current interrupt service routine is being executed, and, if so, for storing the interrupt request associated therewith in an interrupt stack: and an interrupt service routine execution unit for executing an interrupt service routine associated with the new interrupt request value read from the interrupt staging unit, wherein the interrupt service routine execution unit also detects completion of the interrupt service routine, determines whether the interrupt staging unit contains another value representative of an interrupt request and, if so, executes an interrupt service routine associated with the interrupt request value read from the interrupt staging unit and, if not, retrieves an interrupt request, if any, stored at the top of the interrupt stack and the context saved in the context storage unit and resumes execution based upon that context..