1. Why is there a decoder in a register file? Give one or more examples of its role.

2. What does a tristate control accomplish, with respect to a data bus?

3. Write the truth table for a 2 to 4 decoder.

4. Create a circuit implementation of the truth table you gave for the previous problem.

5. Write a Verilog module using the implementation you provided in the previous question.

6. Does it make sense to use a decoder both for registers begin read and for registers being written? Why or why not?

7. If each of the registers in the register file had an enable, en- abling it for write, as well as the clock input, would we still use a decoder for registers being written? Why or why not?

8. What difference to the register file circuit would be made, if the previously mentioned enable on the register were used?

9. Explain the role of the program counter in a computer.

10. Why is it important to be able to load the register in the program counter?

11. Explain the role of the multiplexers in the program counter.