Avbrottvektortabell

Avbrottvektortabell, often abbreviated as interrupt vector table (IVT), is a crucial data structure in computer systems, particularly in operating systems and embedded systems. It serves as a lookup table that stores the memory addresses of interrupt service routines (ISRs). When an interrupt occurs, such as a hardware device requesting attention or a software exception being triggered, the processor uses the interrupt vector number to find the corresponding entry in the IVT. This entry then points to the specific ISR that will handle the interrupt.

The structure of an IVT can vary between different processor architectures. Typically, it is an array of pointers, where each pointer corresponds to a unique interrupt vector. The size of the IVT is determined by the number of distinct interrupt sources the system supports. For instance, a system with 256 possible interrupts would have an IVT capable of storing 256 addresses.

The IVT plays a vital role in efficient interrupt handling. Instead of the processor having to poll each device to check for interrupts, the interrupt mechanism allows devices to signal the processor directly. The IVT then enables a rapid transition to the appropriate handler code, minimizing the overhead associated with interrupt processing and ensuring timely responses to events. Without an IVT, managing multiple interrupt sources would be significantly more complex and less performant.