A CPU has the same register set and memory access as the Very Simple CPU, but a different

instruction set.

a$)$ Complete the ISA by specifying the four new instructions, their instruction codes, and their

overall functions. You can choose any functions you wish, but you must include at least one

instruction that gets an operand from memory and at least one instruction that does not. $(10/50)$

b$)$ Show the state diagram and RTL code for the CPU. $(20/50)$

c$)$ Design the register section, ALU, and control unit for the CPU. Include the hardware to generate

all control signals. Feel free to start with the hardware for the Very Simple CPU and modify it

for the new CPU. $(\frac{15}{50})$

d$)$ Trace the fetch, decode, and execute cycles for each instruction to verify the CPU implements the

ISA correctly. Your solution should follow the format of Table $6\mathrm{.}4.(5/50)$