Answer Happy

5. Complete problem 3.12 from the text book. Space for work provided on the following page. 3.12. A numeric keypad (numpad) generates a 4-bit code as shown in Fig. 3.29. We want to design a logic circuit that converts each 4-bit code to an array of 7 LEDs (called 7-segment display) as shown in Fig. 3.29. A LED is ON it is given a logic value of '1'. A LED if OFF if it is given the logic value of '0'. • Complete the truth table for each output (a, b, c, d, e, f, g). An example is provided for "1001." 4 • Provide the most simplified expression for each output (a, b, c, d, e, f, g). Use K-maps. Note: It is safe to assume that the codes 1010 to 1111 will not be produced by the numeric keypad. 123 y 456 1 ? 7 8 9 W 0 Value x y z w abcdefg 0 0000 1 0001 2 0010 0011 0100 0101 0110 0111 1000 01234 5: 6: 7: 1001 1111011 1010 1011 56789 1100 1101 1110 1111 relationship between keys and 4-bit outputs. FIGURE 3.29. Problem 3.12: Numpad and Complete the truth table for the circuit '?'. Source: Daniel Llamocca 456959