$($a$)$ Identify the main architectural features of FPGA devices that make

these devices versatile when compared with PLD $($PLA$,$ PAL, etc.$)$

devices used to implement digital logic circuits.

$(7$ marks$)$

$($b$)$ Design and implement a digital circuit that converts $4-$bit sign$-$

magnitude represented integers $($ranging from $-7$ to $+7)$ to $4-$bit $2\text{'}$s

complement representation. The circuit has four inputs $($a$3,$ a$2,$ a$1,$

aO$)$ and four outputs $(Z_3,Z_2,Z_1,Z_0).$

Show your complete work including the truth table. K$-$map based

simplification and your overall circuit design must employ minimum

number of $2-$input gates.