Using External interrupt in MSP430G2553 for overload detection

Hi all,

Is there anyone who can guide me as how to implement External interrupt in MSP430G2553. My actual work is to detect the overload/short circuit condition in the circuit and execute some task whenever a condition is met. For overload/short circuit detection i am using Lm358 opamp and the output of the opamp will go to one of the pin of microcontroller.

Thank you..!!