Design a circuit for determining the 9's compliment of a BCD number by using 4-bit binary adder and some external logic gates?
Compliment of a BCD number
9's compliment is nothing but subtracting the provided number from 9. Therefore by using a 4 bit binary adder we can merely subtract the provided binary number by 1001(that is 9). Now we can use the 2's compliment process addition.