Exam 2 will cover course material up through the sequential Verilog lecture. The exercises on the exam will be similar to what you have seem on homework, so looking over you homeworks again is one of the most efficient ways you can prepare for the exam.

The topics covered since the last exam:

As I said in lecture, exam 2 will very much focus on more recent topics, but you will struggle if you have completely forgotten, say, how to turn a basic combinational function into gates.