1. Write Your First Name in ASCII Code with Even Parity

ECE 223 HOMEWORK I

Deadline: 23-10-09

1. Write your first name in ASCII code with even parity 2. Convert decimal 8723 to hexadecimal, octal, BCD and ASCII codes. For ASCII, an even parity bit is to be appended at the left. 3. Formulate a weighted binary code for the decimal digits, using weights a) 6, 3, 1, 1 b) 6, 4, 2, 1 4. Perform subtraction on the given unsigned binary numbers using the 2’s complement and 1’s complement of the subtrahend. a) 10011-10001 b) 110000-10101 c) 1001-101000 5. Simplify the following Boolean expressions to a minimum number of literals and draw the logic diagrams. a) xyz’ + x’yz + xyz + x’yz’ b) (x + y’ + z’)(x’ + z’) c) ABCD + A’BD + ABC’D (to two literals) 6. For the Boolean function F= xy’z + x’y’z + w’xy + wx’y + wxy a) Obtain the true table of F and write minterms and maxterms with symbols. b) Draw the logic diagram, using the original Boolean expression. c) Use Boolean algebra and Karnaugh map to simplify the function to a minimum number of literals. d) Obtain the truth table of the function from the simplified expression and show that it is the same as the one in part (a). e) Draw the logic diagram of simplified expression using only NAND gates. f) Draw the logic diagram of simplified expression using only NOR gates 7. Implement the following expressions with three half adders D= A $ B $ C ($=XOR) E=A’BC + AB’C F=ABC’ + (A’ + B’)C

Reference Book: Mano, Ciletti, ‘Digital Design’