Interrupt Handler - General Sequence Followed When Interrupts Occur By An External Device

General Sequence Followed When Interrupts Occur By An External Device

  1. Interrupt request(IRQ) signal is sent by the device to the processor.
  2. If the interrupt line is enabled the following sequence of events occur in the system, else the interrupt is ignored. The processor completes its present instruction (if any) and pays attention to the IRQ.
  3. It stores the address of the next location and content of status register to the stack
  4. It informs the device that its request has been granted and in response the device de-activates its IRQ.
  5. Using some suitable technique the processor loads its program counter(PC) with address of the ISR.
  6. With return statement occurring at the end of the ISR all stored content is loaded back into the respective registers and the processor resumes its suspended program*.
  • In preemptive scheduled operating systems the processor's control is given to process scheduler instead of the interrupted process.

Read more about this topic:  Interrupt Handler

Famous quotes containing the words general, sequence, interrupts, occur, external and/or device:

    A general is just as good or just as bad as the troops under his command make him.
    Douglas MacArthur (1880–1964)

    Reminiscences, even extensive ones, do not always amount to an autobiography.... For autobiography has to do with time, with sequence and what makes up the continuous flow of life. Here, I am talking of a space, of moments and discontinuities. For even if months and years appear here, it is in the form they have in the moment of recollection. This strange form—it may be called fleeting or eternal—is in neither case the stuff that life is made of.
    Walter Benjamin (1892–1940)

    An entertainment is something which distracts us or diverts us from the routine of daily life. It makes us for the time being forget our cares and worries; it interrupts our conscious thoughts and habits, rests our nerves and minds, though it may incidentally exhaust our bodies. Art, on the other hand, though it may divert us from the normal routine of our existence, causes us in some way or other to become conscious of that existence.
    Sir Herbert Read (1893–1968)

    The greatest events occur without intention playing any part in them; chance makes good mistakes and undoes the most carefully planned undertaking. The world’s greatest events are not produced, they happen.
    —G.C. (Georg Christoph)

    The soul, he said, is composed
    Of the external world.
    Wallace Stevens (1879–1955)

    It is my hope to be able to prove that television is the greatest step forward we have yet made in the preservation of humanity. It will make of this Earth the paradise we have all envisioned, but have never seen.
    —Joseph O’Donnell. Clifford Sanforth. Professor James Houghland, Murder by Television, just before he demonstrates his new television device (1935)