By: Masud-ul-Hasan
2
Interrupts
•An interrupt is  the occurrence of an event that causes a temporary suspension of a program while the condition is serviced by another program.
•It is like a sub-routine. CPU cannot execute more than one instruction at a time; but it can temporarily suspend execution of one program, execute another, then return to the first program.
•Difference in interrupt and subroutine is that in an interrupt-driven system, the interruption occur asynchronously with the main program, and it is not known when the main program will be interrupted.
•Program that deals with the interrupt is called as ISR (Interrupt Service Routine).