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When a non-vectored interrupt occurs,does the processor ever look up the vector table ?

Talking of 8085 , is it different ?

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An interrupt address table (otherwise known as "interrupt vector table") allows for the interrupt service routine's location to be changed by software. This only requires the interrupting device to send the ID of the interrupt, which is then used as the offset in the interrupt address table to determine where to relocate the program counter/instruction pointer. This only applies to a vectored interrupt.

Conversely, in a non-vectored interrupt, the peripheral itself provides the address of the interrupt service routine directly to the processor. This requires more time for an interrupt to be serviced, since the address must be retrieved from the interrupting device every time the interrupt is triggered.

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so does it need to look the vector table ? – steve Apr 19 '12 at 9:50
@steve no, the device itself supplies the address of the subroutine. In a vectored interrupt, the processor already knows the address (since it's in the table). – Breakthrough Apr 19 '12 at 9:53

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