Nexys Video Basic User Demo


Features Used

Not Used Used
8 user switches X
8 user LEDs X
5 User Push Buttons X
OLED Display X
4 Pmod ports X
Pmod for XADC signals X
USB-UART Bridge X
Serial Flash for Application Data X
USB HID Host With Mouse X
USB HID Host With Keyboard X
Micro SD card connector X

Description

The Basic User Demo project demonstrates a simple usage of the Nexys Video's GPIO and UART. The behavior is as follows:

  • The 8 User LEDs are tied to the 8 User Switches. While the centerUser button is pressed, the LEDs are instead tied to GND
  • An introduction message is sent across the UART when the device is finished being configured, and after the center User button is pressed.
  • A message is sent over UART whenever BTNU, BTNL, BTND, or BTNR is pressed.
  • The onboard OLED displays the alphabet then a screen saying “This is Digilent's Nexys Video”
  • Note that the center user button behaves as a user reset button

All UART communication can be captured by attaching the UART port to a computer running a Terminal program with 9600 Baud Rate, 8 data bits, no parity, and 1 stop bit.

How to Build and Program

You will need…

1. Vivado 15.1 installed on your computer
2. Nexys Video board from digilent

1. Download the Project

Download the project zip file (DSD-0000430) which can be downloaded here. Once you have downloaded the project, unzip it in the location of your choosing.

2. Load the Vivado Project

In your now unzipped project, open the file NexysVideoGPIO.xpr. This should open your project in Vivado.

*The screenshots below are from another project but should look relatively the same and will work for our purposes.

3. Synthesize, Implement and Generate Bitstream

To complete this step all that you need to do is click Generate Bitstream on the left hand menu towards the bottom. Vivado will run through both Run Synthesis and Run Implementation before it generates the bitstream automatically. If you want, you can click each step by itself in the order of Run Synthesis, Run Implementation and then Generate Bitstream.

4. Connect and Program the Nexys Video

Once you have generated your bit file, Click on the hardware manager and connect to your board by choosing the local server option.

After your board is connected, just click program to load the GPIO demo onto your Nexys Video.

Running the Nexys4 Basic User Demo

This portion will help you run the demo and observe all its features.

1. Using the Switches with Leds

For this section, all the switches are tied to their corresponding led. Every time a switch is toggled, the led directly above it will toggle with it. If the center push button is pressed, all the Leds will be tied to ground

2. Seven Segment Display

The 7-Segment display counts from 0 to 9 on each of its 8 digits. This count is reset when the center button is pressed. Also, single anodes of the 7-Segment display are blanked by holding BTNU, BTNL, BTND, or BTNR. Holding the center button blanks all the 7-Segment anodes.

3. Tri-color Leds

The two tri-color leds are set to gradually change colors at all times. The user cannot affect them in this demonstration.

4. Microphone to PWM Output

The microphone which is next to Pmod connector JC, records audio data and sends it to the mono audio output located at J8. To listen to the mics output, you will need to plug in headphones or a speaker.