General Sequence Followed When Interrupts Occur By An External Device
- Interrupt request(IRQ) signal is sent by the device to the processor.
- 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.
- It stores the address of the next location and content of status register to the stack
- It informs the device that its request has been granted and in response the device de-activates its IRQ.
- Using some suitable technique the processor loads its program counter(PC) with address of the ISR.
- 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:
“In former times and in less complex societies, children could find their way into the adult world by watching workers and perhaps giving them a hand; by lingering at the general store long enough to chat with, and overhear conversations of, adults...; by sharing and participating in the tasks of family and community that were necessary to survival. They were in, and of, the adult world while yet sensing themselves apart as children.”
—Dorothy H. Cohen (20th century)
“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 formit may be called fleeting or eternalis in neither case the stuff that life is made of.”
—Walter Benjamin (18921940)
“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 (18931968)
“The frantic search of five-year-olds for friends can thus be seen to forecast the beginnings of a basic shift in the parent-child relationship, a shift which will occur gradually over many long years, and in which a child needs not only the support of child allies engaged in the same struggle but also the understanding of his parents.”
—Dorothy H. Cohen (20th century)
“A state that denies its citizens their basic rights becomes a danger to its neighbors as well: internal arbitrary rule will be reflected in arbitrary external relations. The suppression of public opinion, the abolition of public competition for power and its public exercise opens the way for the state power to arm itself in any way it sees fit.... A state that does not hesitate to lie to its own people will not hesitate to lie to other states.”
—Václav Havel (b. 1936)
“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 ODonnell. Clifford Sanforth. Professor James Houghland, Murder by Television, just before he demonstrates his new television device (1935)