Atmel ATF1504AS(L) CPLD Development Board - Part 5 - Attach Switches and LEDs to demonstrate the working code

Now you have programmed the board you will need a Switch and two LEDs to show it working.  So lets build that now.

We will also build a more complex set of daughter boards for further experimentation.

Simple wire version

Let's just use the headers on the board for a quick and dirty demo to show the code we have just uploaded to the Dev board actually works.

You will need:

• 2 x resistors 1K Ohm ( for LED's )
  
• 1 x resistor 10K Ohm ( pull down for Switch GND )
  
• 1 x resistor 330 Ohm ( for Switch +5v )
  
• 2 x LED
• 1 x tactile switch
• 6 x jumper wires
• 1 x bread board

You'll notice that pin 17 is connected both the switch and ground via a 10K resistor (pull down). This is so the pin is not floating when +5V is not being passed to it.  If it's allowed to float you will get some really weird results.  It's worth pulling it out just to observe the issue.

When complete one LED will light up.

Pressing the button will light the other LED and turn off the other.

When the button released it will switch back.

    

Simple daughter board version

Now create a couple of daughter boards for more complex code experimentation.