Electronics Explorer - Intro to the Static I/O and Digital Pattern Generator

  • Using the WaveForms Static I/O and Digital Pattern Generator to blink an LED.

Introduction

This is a basic project designed that will demonstrate how to use the digital I/O devices and the Digital Pattern Generator within the WaveForms software. The objective of this project is to assemble a simple LED circuit on the EE Board and control the blinking of the LED with each of the aforementioned instruments.

Materials

  • Electronics Explorer Board w/ Power Supply and USB cable
  • From the Starter Parts Kit:
    • 10 Ω Resistor
    • LED
    • Jumper wire
  • WaveForms Software (download) - WaveForms 3.5.4 is used in this tutorial

Procedures

Blinking an LED with the Static I/O

  1. Connect the EE Board to your PC with the USB cable.
  2. Connect the board's external power supply and flip the Ready switch to the ON position.
  3. Build the circuit.
    • The figure below shows the completed circuit.
  4. Launch the WaveForms Software. The Device Manager will pop up. Click your EExplorer on the list and click Select. The WaveForms main window will now appear.
  5. Click on the icon to open the Static I/O instrument.
    • The window in the next figure will appear.
  6. Since the LED we are using is connected to the row labeled as 31, we are interested in DIO 31 in the Static I/O instrument. Right-click on DIO31 and select Push Button. Notice that it will now change to look like the following:
  7. Now click the virtual button and observe what happens. The LED on the EE Board and the virtual LED in the Static I/O instrument should both light up.
  8. Right-click on DIO 31 again and notice that it can also be configured as a Push/Pull Switch, Three-State Switch, Open Source Switch, and Open Drain Switch. Experiment with these other I/O devices and observe the LED's behavior. Note the characteristics of each I/O device in the list below.
    • The Push/Pull Switch behaves as a standard slide switch.
    • The Three-State Switch has an additional high-impedance state (Z).
    • The Open Source Switch toggles between a logic high (1) high-impedance state (Z).
    • The Open Drain Switch toggles between a logic low (0) and a high-impedance state (Z).
  9. Continue on to the next section to control the LED using the WaveForms Digital Pattern Generator.

Blinking an LED with the Digital Pattern Generator

  1. The same circuit will be used for this portion of the project as well.
  2. Close the Static I/O instrument and return to the WaveForms main window. Click the Pattern Generator icon to open the Digital Pattern Generator.
  3. In the Digital Pattern Generator window, click Add and Signals as shown in the figure below. Doing so will open the Add Signals window, also shown below on the right. Again, we will use DIO 31. Select it and click Add.
  4. You will now see DIO 31 as a signal on the left side of the window. Before configuring the signal itself, set the Scale to Manual and the Time Base (labeled as “Show:”) to 1s/div. Also, make sure the DPG is set to Run Continously.
  5. Right-click on DIO 31 and click on Edit Parameters of “DIO 31”. Configure the parameters as follows:
    • Set Type to Clock.
    • Set Output to PP (Push-Pull).
    • Set the Frequency to 500mHz (0.5Hz).
    • The rest of your parameters should match those shown in the figure below.
  6. Return to the DPG window and click Run. Observe the results.
  7. Experiment with various settings in the parameters window. Try changing the output to Open-Drain (OD) and Open-Source (OS) and observe what happens.
  8. Set the output back to PP. Now try adjusting the frequency value and see what happens.
    • You can also re-open the Static I/O window and observe the behavior of the virtual LED. Note: Above frequencies of 10Hz, the virtual LED is no longer of accurate representation of the circuit's behavior due to USB communication delays.