When an interrupt occurs, the microcontroller will use the vector table to determine which ISR to execute. For example, if the timer 0 overflow interrupt occurs, the microcontroller will jump to the address stored in the vector table at index 0, which is 0x1000. The ISR for timer 0 overflow is located at that address, and it will be executed.
These make up the bulk of the table. Every MCU has different peripherals, so these vectors will point to handlers for: External button presses. UART/SPI/I2C: Data communication events. ADC: When an analog-to-digital conversion is finished. Why is the Vector Table Important? what is vector table in microcontroller
While the exact layout depends on the architecture (ARM Cortex-M, AVR, PIC, etc.), most vector tables follow a similar hierarchy: 1. The Reset Vector When an interrupt occurs, the microcontroller will use
You can't avoid it. Every microcontroller has one. However, if you don't define the vectors properly: These make up the bulk of the table
Think of it as a When something important happens (like a button press, a timer expiring, or a division-by-zero error), the CPU doesn't search for the solution. Instead, it immediately looks up the correct "phone number" (the function's address) in this fixed table and jumps there to execute the code.
Imagine you have a microcontroller with a button connected to an external interrupt pin.