Project Overview- The goal of this project was to create an electronic voting machine for your company, allowing the members of the board of directors to anonymously cast their ballots on decisions. The machine will then calculate whether the decision has passed for failed based on the results of the voting, and was to be created using only and, or, & inverter gates, commonly referred to as AOI logic.
A truth table is a breakdown of a logic function by listing all possible values the fiction can attain. Truth tables typically contain several rows or columns, depending on how many variables are used in the table. The formula 2^X is used to determine how many columns are to be used. In AOI logic, truth tables can be used, along with schematic diagrams, to derive un-simplified logic expressions of the data on said truth table. Logic Expressions are statements using Boolean algebra to express a condition that is either true or false. The logic expression I derived from this truth table is notPVST + PnotVnotST + PnotVSnotT + PnotVST + PVnotSnotT + PVnotST + PVSnotT + PVST.
The unsimplified circuit of the electronic voting machine was created using the logic expression that was derived from the truth table I originally created.
Using Boolean Algebra, I was able to simplify the logic equation into one that is much easier to comprehend; PV+PS+PT+VST. Using that expression, I created the following schematic for a simpler circuit.
- Pre-constructed circuit board
- Breadboard
- Wires
- 74LS08 Integrated circuit
- 74LS32 Integrated curcuit
- LED
First, I had to install the circuit board into the breadboard. Then, I installed the 2-input and gates and 2-input or gate into the board. I then proceeded to install the connections from the board to the gates in similar fashion to how I had designed it on MultiSim 12.0. Afterwards, I powered and grounded each component into the circuit board, ensuring that it would work as long as a power source was plugged into the circuit board. Finally, I installed the LED and resistor, which ensures that the bulb will not burst due to an overload of power.
The final product has finally been completed!