Computer Science – 4.1 Central Processing Unit (CPU) Architecture | e-Consult
4.1 Central Processing Unit (CPU) Architecture (1 questions)
The Interrupt Descriptor Table (IDT) is a data structure used by the CPU to manage and handle hardware interrupts. It's a table containing interrupt descriptors, one for each possible interrupt vector.
Interrupt Vectors: Each hardware device is assigned a unique interrupt vector. This vector is an index into the IDT. When an interrupt occurs, the CPU uses the interrupt vector to locate the corresponding interrupt descriptor in the IDT.
Interrupt Descriptor: The interrupt descriptor contains information about the interrupt handler, including:
- The memory address of the interrupt handler routine (ISR).
- The privilege level required to execute the ISR.
- Information about the flags that should be set when the interrupt is triggered.
When an interrupt occurs, the CPU uses the interrupt vector to fetch the interrupt descriptor from the IDT. It then loads the address of the ISR from the descriptor and transfers control to the ISR, initiating the interrupt handling process. The IDT is crucial for directing the CPU to the correct handler for each type of interrupt.