$1\mathrm{.}43-$bit Binary Adder $(25$ points$)$

In this exercise, you will use the Full Adder subcircuit you just created in the section $1\mathrm{.}3$ to create

a $3-$bit adder. Each adder will have $3$ inputs, two inputs to add and the remaining one for carry$-$in

from the previous bit. It will produce two outputs, one for Sum and the other for Carry$-$out.

$1.$ Design a $3-$bit adder logic circuit on a piece of paper

$2.$ Double$-$click $$main$$ circuit in the explorer pane to go back to the main canvas

$3.$ Create a new label then enter $3-$bit Binary Adder$$ at the bottom of the canvas

$4.$ Click $$Full$\_$Adder$$ subcircuit from the explorer panel and drag it to the canvas.

a$.$ Repeat it to create $3$ full adders.

$5.$ Add $7$ inputs: $2$ for each adder and one carry$-$in input $($always set to $0)$

$6.$ Add $4$ outputs: $1$ for each adder Sum output and one carry$-$out output for the last bit.

$7.$ Properly arrange inputs, outputs, and full adders and make sure they are facing in right

direction.

a$.$ NOTE: you can change the $$Facing$$

property of pins, gates, subcircuits

including your own to North, South, East, or West.

$8.$ Simulate the full adder with the Poke tool.

a$.$ Setting x to $101$ and y to $001$ should result in $110($Sum$)$

$9.$ Save the project.