Patent ID: 6839834

Claim:
A method for processing an interrupt signal using a microprocessor comprising a central processing unit (CPU), an interrupt controller providing an interrupt request to the CPU when the interrupt signal is received by the microprocessor, registers having a context stored therein corresponding to a program being executed by the CPU, and a stack for storing the context while an interrupt is being executed, the method comprising: detecting a receipt of the interrupt request signal by the CPU from the interrupt controller; storing the context from the registers to the stack; verifying that the same interrupt request is still provided to the CPU from the interrupt controller after storing the context to the stack; sending an interrupt acknowledge signal and reading and executing a first instruction of an interrupt subroutine using the CPU if the same interrupt request is still provided to the CPU; and restoring the stored context from the stack to the registers and returning the CPU to an initial state if the same interrupt request is not still provided to the CPU.