VHDL Keyboard Input: Introduction

Project Info
Author: Chris
Difficulty: Medium
Time Invested: 4 Hours

Take a look at the above
tutorials before continuing
to read this tutorial.
           We previously looked at Character Rom and how we could use memory bits inside the CPLD to hold static characters to be called using the LPM function. This was really useful for generating on-the-fly characters for VGA. Now we'll go a step beyond that and use keyboard input.
           They keyboard is just another input device and has a standard protocol to go along with it. There really isn't anything too special about a keyboard. One pin on the PS/2 connector is used for data, one for a clock. The data is clocked out as you tell it to be. Making this in VHDL is far easier than it sounds.

The UP-2 Board

The Byteblaster MV

Purpose & Overview of this project
           For this project/tutorial we want to now get input from a standard PS/2 keyboard. The UP1/UP2 board has a port for a PS/2 keyboard to connect to and all the pins are hardwired to the UP1/UP2 board which makes it even easier for us. The keyboard input we receive will be able to control the bouncing ball from the previous tutorial.