BITS Pilani has its own online admission test called BITSHD. The form is available around last week of April and closing date is after a month i.e. last week of May. The test has two sections, first is general (basic 12th stuff and apti) and 2 is stream oriented.
BITS do not accept GATE score card. Even it has its own financial assistantship (Monthly Stipend or Fee Waiver 40% or Both) that you can avail easily. You just need to crack a basic technical interview and nature of your assistantship depends on the performance.
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This answer ll clear your doubts about the nature of the exam.