Homework Week 3

Noah Smith

1. Repeat the simulation of Half Adder and Full Adder in Section 1. Show the code, code explanations, and simulation results in your report. (10 points)

Here is the code for the full and half adder respectively. I chose to use dataflow handling to simulate both the adder and the test bench. This could be done with a for loop too.

The simulation for the half and full adder are below. ( full adder on top, half on bottom)

2. Design the testbench for the comparator in Section 2. Show the code, code explanations, and simulation results in your report. (10 points)

In this section, I designed the testbench for the two bit comparator using a for loop to iterate from 0-4 on the inputs. You can see in the simulation that the comparator works, and is centered around the MSB.

3. Design the testbench for the 4-bit comparator in Section 3. Show the code, code explanations, and simulation results in your report. (10 points)

The same process as the 2 bit comparator was used to design a testbench for the N bit comparator. The logic needed to be altered slightly to accommodate the customizable size, but using behavioral modeling and a for look this wasn’t hard. I chose to make x and y count up and down at the same time with a slight offset, so that all values of the comparator were explored. This can be seen clearly in the simulation.

4. Implement a 2-bit comparator on the Basys 3 board. Use sw as inputs and led as outputs. Show the code, code explanations, and an embedded Youtube video demonstration in your report. (10 points)

Using the same code from above, the 2 bit comparator was relatively easy to implement on the board. 3 LED’s were used to show greater than, equal too, or less than, with two switches acting as the inputs. Refer to the code above and video demonstration below.

5. In Section 4, design the testbench for the decoder and verify the logic in simulation (use the Dataflow modeling method). Show the code, code explanations, and simulation results in your report. (10 points)

The test bench design for this decoder was simple enough, using another for loop. Code and simulations are below.

6. In Section 5, for the 8x3 priority encoder, find Q2 and Q1, build the module and verify the logic using simulations. Show the code, code explanations, and simulation results in your report. (10 points)

Designing a test bench for the 8x3 encoder was relatively simple with a for loop. As you can see in the code below, each iteration it moves the 1 down a bit by using 2ⁱ and since this is an 8 bit encoder it goes all the way to 2⁸. The simulation worked as planned and demonstrates the 1 moving up the 8 bits and properly encoding into 3 bits.

7. Derive the logic expression of a 4-1 multiplexer. Show the process on a paper, insert it as an image into your report. (10 points)

8. In Section 6, implement a 4-1 multiplexer on your Basys 3 board. Show the code, code explanations, and an embedded Youtube video demonstration in your report. (10 points)

In this demonstration the 0 and 1 switches are used as S0 and S1 respectively. I used a test input of 10101010, or only even bits as 1. You can see in the video when counting up, it only passes a 1 if the S0 and S1 inputs are set to pass even bits, or on an even number.

9. Design/verify an even parity generator and checker in simulation respectively. Implement an even parity checker on your Basys 3 board - use sw as inputs, use leds as output indicators. Show the code, code explanations, and an embedded Youtube video demonstration in your report. (10 points)

Below are the code, simulation, and demonstration of an even parity checker. Test bench was designed with a for loop once again, and for the demonstration, I used switches 0-3 for inputs, and the Led as an output.

10. Implement the design in Section 8 and Section 9 on your Basys 3 board. Show embedded Youtube video demonstration on your report. Show the code, code explanations, and an embedded Youtube video demonstration in your report. (10 points)

Section 8 was revamping our previous home alarm system to use the 7 segment display. Once the 7 segment decoder was created this was a relitilvly simple task, code and demonstration below.

Section 9 was revamping our car park code. This is essentially a counter. We hooked this up to the 7 segment display as well. Code and demonstration below.