External IO and Metastability
Contributors:
Alchitry, Ell C
Introduction
If you’ve gone through the first couple of Alchitry tutorials, you may have been wondering how the inputs and outputs of the top-level module know where to connect on the board. What about the LED name tells the tools what pin on the FPGA to use? Well wonder no more! In this tutorial I’m going to explain the basics of constraint files and dive into some of the dangers of using external signals in your designs.
Required Materials
This tutorial is primarily conceptual, but if you'd like to follow along, you'll need the following materials.
Suggested Reading
If you aren’t familiar with the following concepts, we recommend checking out these tutorials before continuing.
First FPGA Project - Getting Fancy with PWM
An initial project using Alchitry's onboard FPGA to manipulate PWM
Please Note:
If you haven't worked with Alchitry boards before, you will need to head over to their website to get set up and running before continuing with this tutorial.
Get Started with Alchitry's Lucid-FPGA Tutorials
