Events that can trigger interrupts and where do they go?

8051 can be configure so that any of the following events will cause an interrupt : -

1.  Timer 0 Overflow
2.  Timer 1 Overflow
3.  Reception/Transmission of Serial Character
4.  External Event 0
5.  External Event 1

 In other words, we can configure the 8051 so that when Timer 0 Overflows or when a character is sent/received, the appropriate interrupt handler routines are called. Obviously, there need to be able to distinguish between various interrupts and executing different code depending on what interrupt was triggered. This is accomplished by jumping to a fixed address when a given interrupt occurs.

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