Xilinx Intern interview questions

This was Internship position at Hyderabad, India. There was firstly a phone interview in which they asked me simple questions like reverse a string, pointer concepts, array concepts and to implement an operation using logic gates. I do not remember the exact questions. Sorry about that. Then I was called over on-site. There were three interviewers and an HR person, who ensured that the things were going fine. They were mostly looking for confidence on your concepts, whichever field you have quoted on your resume.However that was where I was lacking(confidence). I realized they were looking to hire hardware programmer/test. But were OK if the person didn't know the stuff, as they are going to train them anyway. They asked me: Nyquist Theorem, Finite State Machine and stuff on my resume. The third interviewer was slightly a strict person, unlike the other two who were pretty friendly. He asked me derivations of Fourier Transform, which I forgot. It took me some time to get to a step where from I couldn't get any further. He asked me another question which I didnt know, and that's when I've understood that I bombed my interview. I wouldn't know if there were further any stages of interview, cause I got a reject.

Applied through college. Got interviewed by two managers within two weeks of application. When I first entered they asked me which of the two available places that I wanted. They mainly just went over my CV and looked at my technical history and skipped over my extra curricular activities which made me think that some of their employees may not be very sociable since they didnt seem to care about that aspect. I also got a very quick tour of the building which was quite nice.