Analog Devices interview questions

I applied on its official website and got the HR's email to set a technical interview on phone. The technical interview was organized by two engineers about electrical engineering in that group. It's about a optical sensor demonstration project group. They maybe the engineer of that group. They asked me to describe my experience on my resume and asked me some questions depend on that. Why did you choose DIP microprocessor? Did you use fixed point calculation to develop your project? Which is not expected by me. I didn't pass may because of that question.