Majority Vote Project
The majority vote project was our first major project of the year. The following report will outline how the project was completed from start to finish. The purpose of this activity was to build a voting machine with four possible voters: President, Vice President, Secretary, and Treasurer. In order for the vote to count, the majority of the voters (3 or more) had to vote. In the event of a tie, the President's vote will count as two to break the tie.
-Step one-
The project began by creating a truth table. Inputs P, V, S, and T were added into the truth table with the corresponding binary count. From there, output D was added to show when the a majority decision was made.
Using the truth table, a logic expression was created from the minterms and a quick sketch of the circuit was created.
Using the truth table, a logic expression was created from the minterms and a quick sketch of the circuit was created.
-step two-
Following the initial steps taken in my engineering notebook, I built the circuit in MultiSim. Once the circuit was built, I simulated the voting circuit to make sure it was operating properly.
As I checked each input situation, I checked off the output (seen in the image above). This led me to single out a problem with inputs 1100. From there, I just had to troubleshoot that portion of the circuit to find the error.
As I checked each input situation, I checked off the output (seen in the image above). This led me to single out a problem with inputs 1100. From there, I just had to troubleshoot that portion of the circuit to find the error.
-step three-
Although the previous circuit worked properly, it was very inefficient in regards to the amount of gates used. For this reason, the logic expression was simplified using Boolean Algebra.
When the circuit was completely simplified (or so I thought), I made another schematic sketch.
When the circuit was completely simplified (or so I thought), I made another schematic sketch.
-step four-
Again, the circuit was built and tested in MultiSim. This circuit worked perfectly the first time. Most likely because there were so many less gates to work with.
-step five-
After completing all of the prerequisite work in my notebook and testing the work in MultiSim, I was ready to breadboard the circuit to make sure it would work in practice, and not just theoretically.
Here you can see the breadboard is wired and operating properly.
Here you can see the breadboard is wired and operating properly.
-errors-
Upon further inspection of my circuit, I realized that I did not completely simplify the logic expression.
I could have used six gates total, which would have only needed two chips to complete the entire circuit.
The final logic expression should have read....
D = VST + P(S+V+T)
Either way, this circuit is drastically smaller than the other; however, for future projects, I will spend more time ensuring that simplification is complete before I begin building the circuit.
I could have used six gates total, which would have only needed two chips to complete the entire circuit.
The final logic expression should have read....
D = VST + P(S+V+T)
Either way, this circuit is drastically smaller than the other; however, for future projects, I will spend more time ensuring that simplification is complete before I begin building the circuit.