Find Port E (PE0-PE7) of U1 in the HC11D0 schematic. Assume that the low-order bits (PE0-PE3) contain the 4-bit binary number A and the high-order bits (PE4-PE7) contain the 4-bit binary number B. On a separate piece of paper, make the connections necessary to subtract A minus B using a two's-complement adder/subtractor circuit design. The result of the subtraction is to be read by Port A, bits PA4-PA7.