Interrupts in 8051 What is an Interrupt: It is a requesting mechanism for the peripherals to make the microcontroller interrupt the currently executing program and run the program to service the request. The program that is run upon the interrupt is called an ISR (interrupt service routine) Types of Interrupts in 8051 There are five different sources of interrupts A real life example - Before going to sleep, you set the timer. Then forget what the timer does, and go for sleep. When the timer finishes the counting, it alarms and interrupts you from sleep. You then wake and starts doing your routine. sources of interrupt in 8051 are: Timer-0: Timer-0 interrupts Timer-1: Timer-1 interrupts Serial Rx/Tx INT0 INT1 All interrupts in 8051 are vectored interrupts Interrupt