Interrupt

Signals emitted by hardware or software when a process or an event needs immediate attention.

They alert the Processor to execute a high-priority process requiring suspension of the current working process.

Interrupts are used in computer systems to handle events that require immediate attention, such as input/output (I/O) operations with Peripherals, hardware errors, and software exceptions.

#Interrupts Priority

Interrupt priority is a mechanism that decides the order in which interrupts are serviced by the CPU when multiple interrupts occur simultaneously.

• Simultaneous: several interrupts processed in parallel.
• Nested: a high priority can interrupt a low priority interrupt
• Queued: processed in order according to their priority when the current interrupt finishes.
• Inhibited: while processing an interrupt other interrupts are ignored

#Interrupt Vector Table

Processors use an interrupt vector table to store the addresses of interrupt service routines (ISRs).

The vector table consists of 32/64-bit vector entries that store the address of the instruction where the cpu will jump when/if the interrupt is raised.

#Interrupt Demo

• Interrupt priority
  • Simultaneous
  • Nested
  • Queued
  • Inhibited
• Interrupt Vector Table