CIS 351

Truth Tables and PLA

Fall 2020
  1. The video shows how to make a circuit that detects multiples of 3. Follow a similar procedure to build a circuit that detects multiples of 5. (Fill out the truth table, then complete the circuit diagram.) PLA Pattern
  2. Picture a typical 7-line LED display (e.g., one digit of a typical digital alarm clock --- see the diagram below). You are going to design a combinatorial circuit that controls whether the top-left LED is lit (LED z_2 to be precise). LED z_2 is lit for numbers 0, 4, 5, 6, 8, and 9; and blank for all other inputs --- including invalid inputs. Description of LED digits
    1. Write the truth table for this circuit. (The circuit is for LED z_2 only. Do not include columns for other LEDs.)
    2. Draw the logic diagram for this combinatorial circuit in a "PLA-style".
    PLA Pattern
  3. Video 2 showed how to build AND and OR gates using relays. A NOR gate has the truth table shown below. Design a single relay using the pattern in the video that implements a NOR gate.
    NOR table AND relay OR relay

Updated Monday, 31 August 2020, 4:22 PM

W3c Validation