Asynchronous Interrupts – Examples
Hardware interrupts are generally asynchronous, meaning they can occur at any time and rarely do they occur at the same spot in a program. An interrupt is an asynchronous procedure call the CPU generates in response to an external hardware signal.
Last updated: March 19, 2014
Hardware interrupts are the real interrupts generated by the external world as discussed above. Far call allows us to jump anywhere in the whole megabyte of memory. To return from the target we place both the segment and offset on the stack.
There are many external devices that need the processor’s attention like the
c) Floppy disk
d) Sound card
All of them need real time interrupts at some point in their operation. When the printer is busy printing we cannot send it more data. As soon as it gets free from the previous job it interrupts the processor to inform that it is free now. There are many other examples where the processor needs to be informed of an external event. If the processor actively monitors all devices instead of being automatically interrupted then it there won’t be any time to do meaningful work.