Write a vdhl code for A $8-$bit Adder to add $28-$bit binary numbers $($A$7,$A$6,$A$5,$A$4,$A$3,$A$2,$A$1,$A$0$ and B$7,$ B$6,$ B$5,$ B$4,$ B$3,$ B$2,$ B$1,$ B$0$ with $A0$ and $BO$ being least significant bits$)$ and a $1-$bit Carry$-$in $($Cin$),$ and results in a $4-$bit Sum $(S7,S6,S5,S4,S3,S2,S1,S0)$ and $1-$bit Carry$-$out $($Cout$)$ with the $1-$bit Full Adder component you built. And draw the circuits.