NOTE: Supply new ROM tables in the solution to 7c and 7d. Show how the addi instruction could be added to the FSM similar to how a lui instruction could be added.

7. a) (5) Explain how the finite state machine, described in module 5 and shown again below, can be extended or changed to include support for the addi instruction without changing the behavior of any of the other supported instructions. Specify any new states required and the values of the control bits used in each new state.

b) (5) Assume that the micro-programmed system, described in module 5, is extended or changed to support the addi instruction. Use five hex digits to show each of the micro-instructions in the new micro-program that implements the addi instruction.

c) (3) The table below shows the original contents of Dispatch ROM 1:

Show any changes or new entries required for dispatch ROM 1 to support the addi instruction.

d) (3) The table below shows the original contents Dispatch ROM 2:

Show any changes or new entries required for dispatch ROM 2 to support the addi instruction.

Dispatch ROM 1 \begin{tabular}{|c|c|c|} \hline Op & Opcode name & Value \\ \hline 000000 & R-format & 0110 \\ \hline 000010 & jmp & 1001 \\ \hline 000100 & beq & 1000 \\ \hline 100011 & 1w & 0010 \\ \hline 101011 & sw & 0010 \\ \hline \end{tabular} Dispatch ROM 2 \begin{tabular}{|c|c|c|} \hline Op & Opcode name & Value \\ \hline 100011 & 1w & 0011 \\ \hline 101011 & sw & 0101 \\ \hline \end{tabular}