(Solved): Design an 8-bit serial adder/subtractor. The augend/minuend is a[7:0] and the addend/subtrahend is ...

Design an 8-bit serial adder/subtractor. The augend/minuend is $$a[7:0]$$ and the addend/subtrahend is $$b[7:0]$$. There is a load input to load the operands into the parallelin, serial-out shift registers, and a mode input to indicate an add operation (mode $$=0$$ ) or a subtract operation $$(\mathrm{mode}=1)$$. Then implement the adder/subtractor as a structural module. Obtain the test bench and apply input vectors for addition and subtraction. Obtain the outputs and the waveforms.