This problem concerns the design of a multiplier for unsigned binary numbers that multiplies a 4-bit number by a 16-bit number to give a 20-bit product. To speed up the multiplication, a 4-by-4 array multiplier is used so that we can multiply by 4 bits in one clock time instead of by only 1 bit at each clock time. The hardware includes a 24-bit accumulator register that can be shifted right 4 bits at a time using a control signal Sh4. The array multiplier multiplies 4 bits by 4 bits to give an 8-bit product. This product is added to the accumulator using an Ad control signal. When an St signal occurs, the 16-bit multiplier is loaded into the lower part of the A register. A done signal should be turned on when the multiplication is complete. Since both the array multiplier and adder are combinational circuits, the 4-bit multiply and the 8-bit add can both be completed in the same clock cycle. Do NOT include the array multiplier logic in your code; just use the overloaded €œ*€ operator. If D and E are 4-bit unsigned numbers, D * E will compute an 8-bit product.
(a) Draw a state graph for the controller (10 states)
(b) Write Verilog code for the multiplier. Use two always blocks (a combinational always block and a clocked always block).

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Ld Ad Sh4 A (24 bits) St 16 8- 8- Control Mult. 8-bit adder Done 4x4 array multiplier Mcand A[3:0]