1 With the Parallax USB Oscilloscope Understanding Signals With the Parallax USB Oscilloscope Presented by: Andy Lindsay Parallax, Inc.

2 Copyrights and Trademarks This documentation is copyright 2006 by Parallax Inc. By downloading or obtaining a printed copy of this documentation or software you agree that it is to be used exclusively with Parallax products. Any other uses are not permitted and may represent a violation of Parallax copyrights, legally punishable according to Federal copyright or intellectual property laws. Any duplication of this documentation for commercial uses is expressly prohibited by Parallax Inc. Duplication for educational use is permitted, subject to the following conditions: the text, or any portion thereof, may not be duplicated for commercial use; it may be duplicated only for educational purposes when used solely in conjunction with Parallax products, and the user may recover from the student only the cost of duplication. BASIC Stamp, Stamps in Class, Board of Education, Boe-Bot SumoBot, SX-Key and Toddler are registered trademarks of Parallax, Inc. HomeWork Board, Propeller, Ping))) Parallax, and the Parallax logo are trademarks of Parallax Inc. If you decide to use trademarks of Parallax Inc. on our web page or in printed material, you must state that "(trademark) is a (registered) trademark of Parallax Inc.” upon the first appearance of the trademark name in each printed document or web page. Other brand and product names are trademarks or registered trademarks of their respective holders.

3 Chapter 1, Page 1 Software Versions and Stamps in Class Version 4.0 Facts ► Version 4.0 Facts ►  For Windows 2K/XP  Compatible with Understanding Signals v1.0  Includes FFT and Zoom functions  Includes Help file ◄ Version 5.0 (Beta) Facts ◄ Version 5.0 (Beta) Facts  For Windows XP/Vista.  150 % Faster Refresh Rate  Variable Persistence Display feature  Does not have FFT, Zoom, or Help

4 Chapter 1, Page 1 Software and Hardware Installation  Say something  Say something else

5 Chapter 1, Page 1 Calibrating your Probes

6 Chapter 1, Page 1 What is an Oscilloscope?  Analog vs. Digital  Digital Storage Scopes  Triggering  Oscilloscope Safety: Remove metallic jewelryRemove metallic jewelry Hands clean/dryHands clean/dry No food or drinksNo food or drinks Anti-stat mat if availableAnti-stat mat if available 20 V maximum20 V maximum If anything gets hot, disconnect it.If anything gets hot, disconnect it. ALWAYS disconnect power to your circuit before leaving workstation.ALWAYS disconnect power to your circuit before leaving workstation.

7 Chapter 1, Pages 7 – 10 The Oscilloscope Display Areas Plot Area Indicator Plot Area Files/Settings, Trigger, Cursors and Measurements Tabs Horizontal, Vertical, FFT and Run/Stop Controls Cursors and Auto Measurements Display Screen

8 Chapter 1, Page 11 Files/Settings Tab Trigger Tab

9 Chapter 1, Pages Cursors Tab Measurements Tab

10 Chapter 1, Activity #1, Pages Circuit: Figures 1-14 and 1-15 on page 15. Program: PinHigh.bs2 on page 16. √ Follow the checkmarks on pages

11 Chapter 1, Activity #2, Pages Program: ToggleIO.bs2 √ Follow the checkmarks on pages

12 Chapter 2, Pages DO PULSOUT 5, 500 PULSOUT 5, 500 PAUSE 20 PAUSE 20LOOP

13 Chapter 1, Activity #1, Pages Circuit: Figure 2-2, p. 25 and Figure 2-3, p. 26

14 Chapter 2, Activity #1, Pages Program: ServoCentering.bs2 on page 29 √ Follow the checkmark instructions on pages

15 Chapter 1, Activity #1, Pages Program: ServoSweep.bs2, p.31 √ Follow the checkmarks on page 31.

16 Chapter 3, Activity #1, Pages Circuit: Figures 3-3 and 3-4, p. 37 Program: TestPiezoWithFreqout.bs2, p. 38 √ Follow the checkmarks on pages

17 Chapter 3, Activity #1, Pages Digitally Synthesized Sine Wave

18 Chapter 3, Activity #2, Pages Program: Start with TestPiezoWithFreqout.bs2 √ Follow the checkmark instructions on pages

19 Chapter 3, Activity #3, Pages Program: DualSineWaves.bs2 on page 44. √ Follow the checkmark instructions on pages 44 and 46.

20 Chapter 4, Pages Resistor/Capacitor Networks Time Constant = R x C Where R is in ohms, C is in farads, T is in seconds

21 Chapter 1, Activity #1, Pages Circuit: figures 4-4 & 4-5, pp Program:RCTimeConstant.bs2, p. 54 √ Follow checkmarks on pages

22 Chapter 1, Activity #1, Pages Circuit: Figures 4-9 and 4-10 on page 58 Program: RCTimeConstantWithPhotoresistor.bs2

23 Chapter 4, Activity #2, Pages √ Follow the checkmark instructions on pages

24 Chapter 5, Activity #1, Pages Circuit: Figures 5-1 and 5-2 on page 66 Program: ShiftinA2DExample1.bs2 √ Follow the checkmark instructions on pages 6 and 7.

25 Chapter 5, Activity #1, Pages √ Follow the checkmarks on pages

26 Chapter 6, Page 73 Asynchronous Serial Communication

27 Chapter 6, Activity #1, Pages Circuit: Figures 6-2 & 6-3, p. 74 – 75 Program: AsynchSerial.bs2, p. 76 Follow checkmark instructions on pages 75 – 76 and page 78.

28 Chapter 6, Activity #2, Page 79 Program: Start with AsynchSerial.bs2 √ Follow the checkmarks on page 79.

29 Chapter 7, Activity #1, Pages Pulse Width Modulation with Infrared √ Assemble your Infrared LED assembly as shown below.

30 Chapter 7, Activity #1, Pages Circuit: Figures 7-3 & 7-4, pp Program:38kHzInfrared.bs2 on page 85 √ Follow the checkmarks on pages

31 Chapter 7, Activity #1, Pages Object Detection with the Debug Terminal Program: 38kHzInfraredWithDetect.bs2, p. 86 √ Follow instructions on pages 86 – 87.

32 Chapter 7, Activity #1, Pages Using the External Trigger Program: 38kHzInfraredWithVaryingFrequency.bs2, p. 89 √ Follow the checkmarks on pages

33 Chapter 7, Activity #2, Pages Program: DecodeSonyIrRemote.bs2, p. 92 √ Follow the checkmark instructions on pages 91 – 92 and page 95.

34 Chapter 8, Pages Operational Amplifiers ▼ Schematic Symbol Op-Amp Output with slow Slew Rate ▼ Op-Amp as a Buffer ▼ The LM358 outputs 20 mV V Op-Amp Output with a Slow Slew Rate ► Op-Amp Output with a Slow Slew Rate ► Supply Voltage Fact An Op-Amp cannot create output signals any larger than the voltage applied at the Vcc and Vee pins, minus “headroom.”

35 Chapter 8, Pages An Op-Amp used as a Voltage Amplifier ▼ Inverting Voltage Amplifier Circuit ▼ Non - Inverting Voltage Amplifier Circuit Gain = -Rf/Ri Gain = Rf/Ri + 1

36 Chapter 1, Activity #1, Pages Circuit: Figure 8-8, p. 106 and 8-9, p. 107 √ Use 2 kΩ for Ri and 1 kΩ for Rf

37 Chapter 8, Activity #1, Pages Program: OpAmpExampleWithFreqout.bs2, page 109 √ Follow the checkmark instructions on pages 108 and 109. Ri = 2 kΩ Rf = 1 kΩ Gain = Rf/Ri +1 Gain = ½ + 1 = 1.5

38 Chapter 8, Activity #1, Page 110 √ Follow the checkmark instructions on page 110. Ri = 1 kΩ Rf = 1 kΩ Gain = Rf/Ri +1 Gain = = 2 Here, the top of the output signal is clipping because the 9 V battery is nearing the end of its useful life

39 Chapter 8, Activity #1, Page 111 √ Follow the checkmark instructions on page 111. Ri = 1 kΩ Rf = 2 kΩ Gain = Rf/Ri +1 Gain = = 3 The output signal is now clipping severely as the 9 V battery fails

40 Chapter 1, Activity #1, Pages Circuit: Figures 8-14 and 8-15 on page 114

41 Chapter 8, Activity #2, Pages Program: OpAmpExampleWithFreqout.bs2, page 109 √ Follow the checkmark instructions on page 115. Ri = 10 kΩ Rf = 20 kΩ Gain = -Rf/Ri = 2 DC Offset Applied with Potentiometer