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Cmod A7 GPIO Demo
Overview
Description
This VHDL project demonstrates the basic use of most of the Cmod-A7's general purpose I/O.
- The two user LEDs are tied to the two push buttons
- The RGB LED is set to smoothly change colors
- The UART bridge outputs a beginning message and a status message whenever a button is pressed
Features Used
| Not Used | Used | |
|---|---|---|
| 2 user LEDs | X | |
| 1 tri-color LEDs | X | |
| 2 User Push Buttons | X | |
| 48 GPIO Pins | X | |
| 1 Pmod port | X | |
| Pins for XADC signals | X | |
| USB-UART Bridge | X | |
| 512 kB SRAM | X |
Prerequisites
Hardware
- Cmod A7 FPGA board
- Micro-USB cable
Software
- Vivado Design Suite 2016.4
- Newer versions can be used, but the procedure may vary slightly
- Digilent Board Support Files for Vivado
- Follow the Vivado Board Files for Digilent 7-Series FPGA Boards guide on how to install Board Support Files for Vivado.
Downloads
Cmod A7 15T Project Repository – GIT Repo ZIP Archive
Cmod A7 35T Project Repository – GIT Repo ZIP Archive
Download and Launch the Cmod A7 GPIO Demo
1) Follow the Using Digilent Github Demo Projects Tutorial. This is an HDL design project, and as such does not support Vivado SDK, select the tutorial options appropriate for a Vivado-only design. Make sure that you download the version of the project that applies to your specific board - the 15T or 35T version. Return to this guide when prompted to check for extra hardware requirements and setup.
2) In order to fully use the demo, you will need to connect a serial terminal to your Cmod A7. Plug your board into your computer with a Micro USB cable and make sure the board has power. Then open a serial terminal (such as TeraTerm) on your computer. In the terminal application setup the serial port to connect to the appropriate port for your board, with a baud rate of 9600. Then return to the Github Projects Tutorial to finish programming and running the demo.
Using the Cmod A7 GPIO Demo
1. LEDs and Buttons
When a button is pressed, the corresponding LED will light up.
The RGB LED smoothly transitions between colors.
2. UART Messages
Connect a terminal program with the settings 9600 baud rate, 8 bits, one stop bit, and no parity bit. On reset, the board will display “CMOD A7 GPIO/UART DEMO!”
Whenever a button is pressed, the message “Button press detected!” is sent over UART.
