Upon activation of an interrupt, the microcontroller goes through the following steps 1. It finishes the instruction it is executing and saves the address of the next instruction (PC) on the stack 2. It also saves the current status of all the interrupts internally (i.e: not on the stack) 3. It jumps to a fixed location in memory, called the interrupt vector table, that holds the address of the ISR this is available in mazithi's book's,look at the highlighted case,if not in the stack where it ll be saved
For the 8051, the so-called "vector" table holds code to be executed - not the address of the ISR (as for many other architectures).
To make a jump from the so-called "vector" location, you have to code a Jump instruction...