ESS Technology interview questions

Remote video call. The interviewer did not introduce himself, the company, or describe the position. He simply said "hello" and dived right into technical questions. I was told the interview would be about C programming skills, but I was asked multiple hardware questions. Other questions were vague and hard to understand. The interviewer did not give me a chance to ask my own questions at the end. The interview felt very unprofessional to me.