I was invited to a pooled campus interview. My college and another college took part in it. All the interview details were provided before hand. On the interview day, first, we were provided with a pre placement talk. There were 3 rounds: Written, Technical Interview, HR Interview.
Written round was consisted of 2 rounds. First one was Aptitude, Verbal Ability Resoning and all that stuff. Basically questions were easy. But it was like 70 questions to solve in 60 minutes. There were like 6 sections with different number of questions and each section was carrying a sectional cut-off (I guess 60-70%, not clear because nobody told us the figures). At the end of the test if you answered questions correctly with clearing all the sectional cutoffs (no neagtive marking), the screen will flash written Congratulations on it. Then there is a creative writing round. You'll be given a topic or a picture and you have to right a story about that. If you are not exceptional with words, you can also write in simple English. But don't to any spelling or grammatical mistakes. This round will be examinated manually by the TechM officers.
If you are able to pass through the written round, next is technical Round. In Technical Round, There will be 2-3 HRs sitting and students will be called one by one. I think this'll take around 45 minutes. And They'll ask about your peronal life, achievements, typical HR questions and few basic fundamental questions. If you are not from Computer Science or IT, ask them, they may ask your branch related question more. But prepare yourself to answer the simpliest programming question. Clear your concept about looping, function call, polymorphism, sorting etc.
The results'll be declared after everybody completes the Techincal eound. Now the HR round is just 5 minutes job. And if your resume is clean, you have all the documents, photograph ready and you can answer 3-4 questtions in English, you'll be selected. Generally, there'll be one interviewer and he'll call 4-5 students at once. Questions'll be like 'Why CSE/your bracnch ?' 'What is the scenario at your college ?'. Easy questions.