It comprises (WT) of very few questions (10 in CSA,7 in SERC) with a time duration of 30mins. The questions are from basic maths and the core subjects.In CSA, questions come from combinatorics, Probability(poissons distribution) and basic questions from core subjects like Operating systems(theoritical question about pipelining),Compilers(finding all possible strings from a given grammer). Some questions are given about filling the blanks with appropriate code in C to implement a particular logic.SERC written test have mostly mathematics(Engineering mathematics also) with just two questions on coding(fill in the blank) a question on limits and co-ordinate geometry.The questions may be of mcq type, fill in the blanks type and short answer type.One has to attempt all questions to stand a chance for interview. The level of complexity is similar to 1 mark questions in GATE exam.In Interview,Very basic questions and application capability would be tested during the interview. Learn the concepts thoroughly and solve as many problems as possible to learn application of them.

 Hope this helps!!!