70009 Parallax Inc, 70009 Datasheet
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Understanding Signals Student Guide VERSION 1.0 ...
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WARRANTY Parallax warrants its products against defects in materials and workmanship for a period of 90 days. If you discover a defect, Parallax will, at its option, repair, replace, or refund the purchase price. Simply call for a Return Merchandise ...
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Parallax Educators – This focus group of 100 members consists exclusively of educators and those who contribute to the development of Stamps in Class curriculum. Parallax created this group to obtain feedback on our curriculum development and to provide a ...
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Preface........................................................................................................................iii Copyright and Reproduction .......................................................................................... iv Foreign Translations ...................................................................................................... iv Special Contributors ...................................................................................................... iv Chapter #1: Oscilloscope Basics..............................................................................1 What is an Oscilloscope? ...............................................................................................1 How Does an Oscilloscope Work? .................................................................................2 Running the OPTAscope 81M for the First Time............................................................5 Plot Area ....................................................................................................................6 ...
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Chapter 4: R/C Circuits and Variable Resistors.................................................... 49 What are Capacitors?................................................................................................... 49 Resistors and Capacitors in RC Networks ................................................................... 49 Activity #1: Verifying the Calculated Resistor/Capacitor Time Constant ...................... 52 Activity #2: Variable Resistors Network......................................................... 57 Summary ...
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Preface This text demonstrates how to use the OPTAscope 81M as an oscilloscope by viewing common signals generated by sensors and the Parallax BASIC Stamp. Most of the circuits and examples used in this guide are drawn from other Parallax ...
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BASIC Stamp-generated signals in projects found throughout the Stamps in Class series of textbooks COPYRIGHT AND REPRODUCTION Parallax grants you under a conditional right the ability to download, duplicate, and distribute this text without ...
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Chapter #1: Oscilloscope Basics Using an oscilloscope makes it much easier to characterize and understand the signals coming from a sensor or microcontroller. Understanding Signals assumes you’ve never used an oscilloscope. For the OPTAscope 81M value to ...
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Figure 1-2 provides an example (millisecond) of time, read from left to right. To accomplish this, the oscilloscope samples the input signal, or waveform very specific rate called the sample rate. The OPTAscope has a ...
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The trigger controls when the oscilloscope will start recording the input signal. The trigger allows you to capture and view only the segment in which you are interested. The criteria controlling the trigger action is called a trigger event. The ...
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OSCILLOSCOPE SAFETY Before test-driving your OPTAscope 81M important for you to be aware of the general safety guidelines for working with oscilloscopes. Working with oscilloscopes requires you to work on circuits with live voltage. Live voltage can and ...
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RUNNING THE OPTASCOPE 81M FOR THE FIRST TIME Setting up the OPTAscope is a matter of installing the software from the CD provided, and connecting the OPTAscope to your PC via a standard USB cable (included). You may also obtain ...
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Figure 1-4: The OPTAscope hardware setup detailed in the on-line help file Don’t be afraid if you change the settings to an unknown state. You can always reload the factory default settings this, select File → Load Factory ...
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The red and blue arrows to the left are handles that allow you to adjust the vertical position of the signals. This will allow you to arrange the signals within the Plot Area as you wish, perhaps separating them for ...
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The Vertical dial, representing volts per division, sets the voltage scale on which the input signal will be displayed. Example: if the Vertical dial is set V/Div) and the signal displayed is 2½ divisions above the ...
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Run/Stop button again. You will see it depress, indicating the oscilloscope is idle. The FFT button opens the Fast Fourier Transformation window (Figure 1-7). The OPTAscope’s Fast Fourier Transformation (FFT) function emulates a device called a ...
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When the vertical line in the blue bar is lined up with the “ T ” in the trigger position arrow, the trigger event will line up in the center of the ...
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Trigger Tab Clicking the Trigger tab brings up a menu which allows you to set the Trigger Source , Trigger Edge , Trigger Mode , and Run/Stop Mode switches (Figure 1-11). The Trigger Source switch selects the channel monitored by ...
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Auto mode is great as a first step to make sure you have the oscilloscope setup correctly. However, if the trigger event occurs infrequently, you may never see the signal you are looking for while in Auto mode. In that ...
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The Reset Plots button will reset all plots to their default values. This button allows you to zoom out after you have zoomed in, and will also reset the Autoscale . Cursor menu functions can also be accessed by right-clicking ...
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All activities in this text assume that you are using a fresh 9 V battery as your power supply. Please be aware that using worn-out batteries or alternative power supplies may alter your voltage signals somewhat from those shown in ...
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P14 OPTA OPTA Vss Vdd X3 P15 P14 P13 P12 P11 P10 Configuring the OPTAscope Software √ Open the OPTAscope software. Figure 1-14: scope CH1 High and Low signals ...
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Set up the OPTAscope to display the signal as shown in Figure 1-16. Remember, click on and drag the arrow to the left of the Plot Area to set the trigger voltage. CH1 CH2 Horizontal Dial Trigger Source Trigger ...
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Change the command to HIGH 14 If you could watch the OPTAscope Plot Area while you programmed the BASIC Stamp, you would see the signal change from high ( low (0 V). Now you can see that ...
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ACTIVITY #2: USING THE HORIZONTAL DIAL AND EDGE TRIGGERING This activity will demonstrate how to use the OPTAscope’s Horizontal dial to display different periods of a signal, and how to trigger on a rising or falling edge of a signal. ...
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You should now see a square wave in the Plot Area, as shown in Figure 1-19. The BASIC Stamp is toggling an I/O pin, that is, switching between the cursors, we can measure how long the signal is high. It ...
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Set the Trigger Mode switch back to Normal . Notice the Plot Area never updates, because the OPTAscope will now only trigger with valid trigger events. Since the input signal cannot trigger a valid event, there is nothing new ...
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Summary An oscilloscope is a device that allows one to view graphic representations of electrical signals. Oscilloscopes are delicate pieces of electronic test equipment that must be used safely and cared for properly. Simple oscilloscopes, such as the OPTAscope, offer ...
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It is available online from the Stamps in Class Curriculum menu on the Education page at www.parallax.com. “XYZs of Oscilloscopes”, Tektronix, Tektronix 2003 Found at http://www.tektronix.com/Measurement/App_Notes/XYZs/, this article provides a very well documented tutorial for using oscilloscopes. The concepts ...
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Chapter #2: Servo Pulse Square Waves PULSE WIDTH MODULATION AND HOBBY SERVOS The focus of this chapter will be to measure and understand the pulses used to control servos. A servo is a type of tiny motor commonly used in ...
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The command is used in the following activities. It has this format: PULSOUT PULSOUT 5, 750 The command’s first argument, 5, states the BASIC Stamp I/O pin to be used, PULSOUT and the second argument, 750 variable or ...
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ACTIVITY #1: MEASURING PULSES FOR SERVO CONTROL In this activity we will create and measure servo pulses using the OPTAscope’s Paired Bars cursors function Parts Required (1) Standard Parallax servo (1) 3-pin male/male header (1) 220 Ω resistor (for the ...
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Vdd Vin X3 P15 P14 P13 P12 P11 P10 Follow these instructions for the HomeWork Board: √ Insert the 3-pin male-male header into the servo lead. This will allow ...
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Servo brand does matter! This circuit was designed to use the Parallax servo included in the Understanding Signals kit, which has a current draw of around 100 mA unloaded. If you are using a different servo that may have a ...
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Vdd Vin X3 P15 P14 P13 P12 P11 P10 Configuring the OPTAscope Software Continue the Activity in the same manner for all boards: √ Open the OPTAscope software and ...
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Measuring the Servo Pulse Widths with ServoCentering.bs2 √ Run the program ServoCentering.bs2. ' Understanding Signals - ServoCentering.bs2 ' Demonstrate a continuous pulse width for servo control ' {$STAMP BS2} ' {$PBASIC 2.5} DO PULSOUT 14, 750 PAUSE 20 LOOP Each ...
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If all goes well, your OPTAscope screen will look like Figure 2-8 and the Auto Measurements box will show the width of the pulse. The Display Screen’s Cursors box will indicate that the pulse measures 1.5 ms wide, as shown ...
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Are your measurements different? Calibrate! If your measurements vary from those in the text, you may try calibrating your OPTAscope to see if that is the source of the discrepancy. To begin, disconnect all probes from your circuit. Then select ...
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DO FOR PulseWidth = 400 TO 1200 STEP 10 DEBUG DEC PulseWidth," uS",CR FOR Counter = PULSOUT 14, PulseWidth PAUSE 20 NEXT NEXT FOR PulseWidth = 1200 TO 400 STEP 10 DEBUG DEC PulseWidth," uS",CR FOR Counter ...
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Summary This chapter demonstrated how to measure a servo pulse signal using the Paired Bars cursor settings option. This chapter also provided a visualization of servo control signals, which will aid in understanding timing and control in your other BASIC ...
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Boe-Bot”, Student Workbook, Version 1.5, Parallax, Inc., 2001 Chapter 2 provides examples with continuous rotation servos available online from the Stamps in Class Curriculum menu on the Education page at www.parallax.com. ...
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Chapter #3: Sine Waves SINE WAVES WITH THE BASIC STAMP FREQOUT COMMAND A sine wave is a common electrical signal that can be viewed on the OPTAscope. Unlike digital signals that typically are either high or low, analog signals can ...
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Note the ratio of on-time vs. off-time as the signal progresses from left to right. You can see that the on-time is progressively increasing while the off-time is progressively decreasing. If this signal were filtered into a smooth DC signal, ...
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P9 Ω 220 1 µF Vss Vdd Vin X3 P15 P14 P13 P12 P11 P10 Configuring the OPTAscope Software √ Configure the OPTAscope with the settings shown in ...
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CH1 CH2 Horizontal Dial Trigger Source Trigger Edge Trigger Mode Run / Stop Mode Trigger Voltage FREQOUT pin, duration, freq1 {,freq2}. FREQOUT is a BASIC Stamp command that generates a series of pulses that approximate a sine wave when filtered. ...
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Figure 3-6: 200 Hz sine wave ...
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Signal Problems? The piezo speaker signal shown below-left resembles the one you can reasonably expect to see when using the piezo speaker included in the Understanding Signals kit. If you are using a different speaker, your OPTAscope display might more ...
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ACTIVITY #2: SINE WAVE FREQUENCY AND AMPLITUDE MEASUREMENT This activity uses the same circuit you have already built. This activity will measure the frequency and amplitude of a sine wave and compare it to the BASIC Stamp code that generated ...
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Figure 3-8. That’s just what we programmed the BASIC Stamp to generate - a 200 Hz sine wave! √ To generate a 500 Hz signal, change the read: FREQOUT 9, 60000, 500 √ Remember ...
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First move the vertical cursors to the centers of the two peaks in the middle to measure the frequency of the sine wave. You should get 500 Hz. √ Record your ∆ V and f measurements, and make a ...
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Dual Sine Waves with the DualSineWaves.bs2 Program You will again reuse the circuit from the previous two activities. √ Set the Vertical dial to 1 V/division and the Horizontal dial to 200 µs. √ Run the program DualSineWaves.bs2. ' Understanding ...
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Fast Fourier Transformation with the DualSineWaves.bs2 Program The OPTAscope’s Fast Fourier Transformation (FFT) function emulates a device called a spectrum analyzer by displaying the sine wave frequencies contained by a signal. Fourier analysis is used extensively by the radio communication ...
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Set the Horizontal dial to 1 ms. You should see a compressed view of the mixed signal. √ Press the FFT button, and the FFT Window will open (Figure 3-11). √ Select Black - Harris in the Windowing box. ...
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The nature of sound is complex: only pure tones are made with one frequency, but most applications use tones made of mixed frequencies. Proper use of the OPTAscope can help you identify the component frequencies within a complex sine wave. ...
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Further Investigation “What’s a Microcontroller”, Student Guide, Version 2.0, Parallax, Inc., 2003 In this text by Andy Lindsay, Chapter 8 features an overview of sound generation, providing a wide variety of frequencies to view and measure available online ...
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Chapter 4: R/C Circuits and Variable Resistors Resistors and capacitors are integral to analog electronics. Anything you do with analog electronics will involve resistors and capacitors. Understanding how they react with each other is important. This chapter will demonstrate how ...
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Where Ωs Where Farads (1µF would be .000001 F, .1µF would be .0000001 F). Time Constant is in seconds Let’s calculate the time constant for a 220 Ω resistor and a 1µF capacitor. Time ...
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V) then disconnect the power supply, it will take 2 ms for the capacitor to discharge to 37% or 1.85 V. This use of capacitors and resistors allows you to use ...
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ACTIVTY #1: VERIFYING THE CALCULATED RESISTOR/CAPACITOR NETWORK TIME CONSTANT In this activity we will measure the resistor/capacitor time constant and verify the value with an OPTAscope measurement. Required (1) 220 Ω resistor (1) 10 µF capacitor (5) Jumper wires WARNING: ...
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Vdd X3 P15 P14 P13 P12 P11 P10 Configuring the OPTAscope Software √ Configure the OPTAscope as shown in Figure 4-6. CH1 CH2 Horizontal Dial Trigger Source Trigger Edge ...
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RCTimeConstant.bs2 to Demonstrate Charge/Discharge Curves √ Run the program RCTimeConstant.bs2. ' Understanding Signals - RCTimeConstant.bs2 ' Read photoresistor in RC-time circuit using RCTIME command. ' {$STAMP BS2} ' {$PBASIC 2.5} DO HIGH 0 HIGH 15 PAUSE 10 LOW 0 LOW ...
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On Channel 1 you will see a charge-discharge curve. On Channel 2 you will see a square wave. Channel 2 displays what the signal would look like without the RC network. This also shows when the capacitor starts to charge ...
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Replace the 220 Ω resistor with a 1 kΩ resistor. If you are using the HomeWork Board, remove the jumper wire you used instead of the 220 Ω resistor, and put the 1 kΩ resistor in its place. √ ...
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Time Constant Time Constant If you are using the HomeWork Board, your calculation must account for the added resistor value: Time Constant Time Constant Time Constant Again, your actual measurements may vary in accordance with the tolerances of the resistor ...
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P15 Ω 220 Vss Vdd X3 P15 P14 P13 P12 P11 P10 Configuring the OPTAscope Software √ Configure the OPTAscope as shown in Figure 4-11. Figure 4-9: RC Network ...
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CH1 CH2 Horizontal Dial Trigger Source Trigger Edge Trigger Mode Run / Stop Mode Trigger Voltage RCTimeConstantWithPhotoresistor.bs2 √ Run the program RCTimeConstantWithPhotoresistor.bs2. ' Understanding Signals - RCTimeConstantWith Photoresistor.bs2 ' Read photoresistor in RC-time circuit using RCTIME command. '{$STAMP BS2} '{$PBASIC ...
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Converting RCTime units to milliseconds is done in the following PBASIC line of code: DEBUG HOME, "(time/1000)*2 = ", DEC3 (time/1000)*2 RCTIME The command measures in units of 2 microseconds, but OPTAscope displays in units of milliseconds. The (time/1000)*2 instruction ...
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Figure 4-12: Using the Paired Bars cursors to measure capacitor discharge time ...
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Calculate the resistance of the photoresistor with the following formula: Table 4-1: Known Values at the Instant VP15 Crosses the Threshold Voltage Values Vdd = 5.0 volts The initial condition of the voltage at P15. VP15 = 1.4 volts ...
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Summary This chapter demonstrated resistor/capacitor charge signals. It also showed how to use the OPTAscope to verify a calculated constant for an R/C network. Finally we demonstrated how to calculate a value of an unknown resistance, given the value of ...
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Chapter 5: Synchronous Serial Communication Data can be transmitted in either of two fashions: parallel or serial. Between the two, parallel data transmission is the fastest method, but it requires many I/O lines. Serial data transmission generally requires 1, 2, ...
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/CS Vcc 1 8 Vin (+) CLK 2 7 Vin (-) GND Vref 4 5 ADC0831 Vss Vdd Vin X3 P15 P14 P13 P12 P11 P10 ...
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Configuring the OPTAscope Software √ Configure the OPTAscope as shown in Figure 5-3. CH1 CH2 Horizontal Dial Trigger Source Trigger Edge Trigger Mode Run / Stop Mode Trigger Voltage Demonstrating Synchronous Serial with ShiftiA2DExample.bs2 √ Run the program ShiftinA2DExample1.bs2. ' ...
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Subroutines ]----------------------------------------------------- ADC_Data: HIGH CS LOW CS LOW CLK PULSOUT CLK, 210 SHIFTIN DataOutput,CLK,MSBPOST,[adcBits\8] RETURN Display: DEBUG HOME DEBUG "8-bit binary value: DEBUG CR, CR, "Decimal Value: ", DEC3 adcBits RETURN √ Use the red and blue arrows ...
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The lines in Figure 5-4 indicate the rising edge of the clock. Where that line meets the data signal is the value of the data signal that will be received by the BASIC Stamp. Let’s take a look at the ...
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Figure 5-5: OPTAscope and Debug Terminal display binary 80 Above: note the clock line (red - top) and data from the ADC0831 (blue – bottom) which is binary 01010000, or decimal value of 80. Below: The Debug Terminal displays each ...
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Next, we will replace the clock line signal with the analog input voltage signal on Channel 2. There is only one addition to make to the circuit. √ Add a jumper wire to the breadboard between the ADC0831 Pin 2 ...
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Summary This chapter examines the nature of the synchronous serial protocol used by the BASIC Stamp to communicate with the ADC0831. The clock signal, data signal and analog input were viewed. The activity demonstrated how to configure the OPTAscope with ...
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Chapter 6: Asynchronous Serial Communication The word asynchronous means “without a clock.” Asynchronous serial communication only uses one line, the data line, to communicate. The most commonly known type of communication that uses asynchronous communication is the RS-232 serial port ...
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Did you notice that when the transmitter is sending bit 0 it should be high or logic 1? This is because RS-232 is inverted lot of cases it is also level shifted to -12 V for logic 1 ...
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X3 P15 P14 P13 P12 P11 P10 Configuring the OPTAscope Software √ Configure the OPTAscope as shown in Figure 6-4. CH1 CH2 Horizontal Dial Trigger Source Trigger Edge Trigger ...
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Position the OPTAscope side-by-side with the BASIC Stamp’s Debug Terminal to see the values in binary being sent by the BASIC Stamp at 9600 bps. Running the AsynchSerial.bs2 Code √ Run the program AsynchSerial.bs2. ' Understanding Signals - AsynchSerial.bs2 ...
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Figure 6-5: Setup to view the 9600 inverted data ...
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Now, let’s change the baud rate and look at the resulting signal. √ Modify the AsynchSerial.bs2. program’s SEROUT 14, 16780, [Value] √ Run the modified program. Now what is happening in the OPTAscope’s Plot Area? Are you able to view ...
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ACTIVITY #2: DISPLAYING 8-BIT TRUE DATA √ Set the Horizontal dial back to 500 µs. √ Modify the program AsynchSerial.bs2 to send true data by changing the command’s argument to read: Baudmode SEROUT 14, 84, [Value] √ Run the modified ...
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Summary This chapter examined asynchronous serial communication protocol. command was explained and used to generate inverted and non-inverted data signals, and signals at different baud rates. The OPTAscope’s Horizontal dial, Zoom function, and Vertical Bars cursors were employed to analyze ...
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Chapter 7: Pulse Width Modulation with Infrared Have you ever wondered how the remote for your TV or VCR works? Infrared is what keeps you on the couch! When you press the power button on your remote control, a unique ...
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Another use for IR is object detection (Figure 7-2). The IR beam reflects off objects just like light. When an IR beam is transmitted out, you can use the detector to look for an echo or reflection. When you transmit ...
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Infrared LED Assembly: Your infrared LED should be assembled before using circuit. There are three parts: the IR LED (emitter), the LED Standoff (large cylinder) and the LED Light Shield (small cylinder). 1. Insert the IR LED ...
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Vdd Vin X3 P15 P14 P13 P12 P11 P10 Configuring the OPTAscope Software √ Configure your OPTAscope as shown in Figure 7-6. CH1 division CH2 2 ...
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Running 38kHzInfrared.bs2 Program √ Run the program 38kHzInfrared.bs2. ' Understanding Signals - 38kHzInfrared.bs2 ' Send a single character to the Debug Terminal ' {$STAMP BS2} ' {$PBASIC 2.5} DO FREQOUT 7,1,38500 PAUSE 20 LOOP √ Separate the signals so that ...
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Object Detection with the 38kHzInfraredwithDetection.bs2 program. Since the BASIC Stamp can’t multitask, it cannot read the output of the detector while sending the signal. However, you can successfully read the detector’s output FREQOUT immediately after you send the 40 kHz ...
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IF IR_DETECT = 0 THEN DETECTED DEBUG HOME, "IR DETECTOR OUTPUT IS HIGH, NOT DETECTED" GOTO START DETECTED: DEBUG HOME, "IR DETECTOR OUTPUT IS LOW, GOTO START If the IR signal makes it to the detector, the BASIC Stamp will ...
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If you move your hand up and down in front of the emitter and receiver, you may see a rapidly varying signal like the one shown in Figure 7-7. This happens when only a portion of the 38.5 kHz signal ...
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Using the External Trigger with 38kHzInfraredwithVaryingFrequency.bs2 √ Configure your OPTAscope with the following settings. Note: to set the external trigger at 10%, press the T button at the top left corner of the Plot Area, click the right T button ...
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In this example we are using the external trigger function of the OPTAscope 81M. This keeps the waveform on the screen and prevents it from jumping around, which is also called false triggering. You can see this by temporarily selecting ...
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In this case, the time per division is 3 ms. Normally there are 50 data points per division, now there are 150 per division. As you can see from Figure 7-9, we have modulated the IR signal to the ...
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CH1 CH2 Horizontal Dial Trigger Source Trigger Edge Trigger Mode Run / Stop Mode Trigger Voltage Autoscale Reading a Remote Control with DecodeSonyIRRemote.bs2 This application program is longer and more complex than the example programs used in the other Activities. ...
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IR_pulse VAR Word(12) counter VAR Nib type VAR Nib IR_message VAR Byte ' -----[ Initialization ]-------------------------------------------------- DEBUG CLS ' -----[ Main Routine ]---------------------------------------------------- DO DO LOOP UNTIL IR_Detect = 0 GOSUB Display_Heading GOSUB Find_and_Display_Start_Pulse GOSUB Process_IR_Pulses GOSUB Display_IR_Pulse_Values GOSUB Convert_to_Binary_Number_Display ...
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ENDIF NEXT RETURN ' -----[ Subroutine - Process IR Pulses ]---------------------------------- Process_IR_Pulses: DO PULSIN IR_detect,active_high,IR_pulse(0) LOOP UNTIL (IR_pulse(0) > 1400) AND (IR_pulse(0) <> The BASIC Stamp 2p and 2SX modules are fast enough to load these ' values ...
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FOR counter = (IR_pulse(counter) < 450) THEN IR_message.LOWBIT(counter ELSE IR_message.LOWBIT(counter ENDIF NEXT DEBUG CR,CR,"Binary Value: ", BIN8 IR_message, CR DEBUG "Decimal Value: ", DEC3 IR_message, CR DEBUG "Without bit-7: " DEBUG " ...
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The pulse train generated by pressing 5 on the remote control is shown in Figure 7-11. You can see that the 10-bit wide data is transmitted LSB (least significant bit) first. You should see the same data in your Debug ...
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Summary This chapter demonstrated several uses for IR, including common circuits and methods used in robotics for object detection. The OPTAscope was triggered using an external trigger connected to a BASIC Stamp I/O pin. This ensured the signal would be ...
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Chapter 8: Operational Amplifiers Amplifiers are used in everything from car stereos to medical equipment. There are many types of amplifiers, each with different characteristics. This chapter will introduce you to simple signal conditioning with an operational amplifier, commonly called ...
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Vcc = 5 V and Vee = GND, a rail-to-rail op-amp could create an output signal as large Vs. INPUT SIGNAL 5V GND 5V 3.5V GND OPAMP OUTPUT LM358, Vcc=5V, Vee=GND The LM358 ...
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Slew Rate INPUT OPAMP OUTPUT The slew rate refers to how fast the op-amp can change its output voltage. The LM358 has a slew rate of 300 mV per microsecond. For every microsecond, the output can change as much as ...
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AN OP-AMP USED AS A BUFFER Sometimes, when connecting two circuits that were designed to each perform a specific function, the connection allows an interaction that makes the new combined circuit behave in unwanted ways. To prevent this unwanted interaction, ...
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AN OP-AMP USED AS A VOLTAGE AMPLIFIER An op-amp can be used to amplify voltage this, you have two types of circuits to choose from, inverting and non-inverting. As you can imagine, the inverting circuit will produce an ...
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Therefore kΩ resistor is needed for Rf, given a 10 kΩ resistor for Ri and a desired gain of 2. Remember, the 10 kΩ resistor in the input impedance of the op-amp. Two 10 kΩ resistors would present ...
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With this configuration, you cannot attenuate the signal like you could with the inverting amplifier; it can only be used to amplify. Let’s look at the formula to calculate gain for this configuration ...
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Calibrate your OPTAscope 81M by selecting Calibrate under the File pull down menu and following the instructions. √ Connect the CH1 and CH2 probes as shown in Figure 8-9. WARNING: The 1.0 µF capacitor can explode ...
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Vdd X3 P15 Rf P14 P13 P12 P11 P10 Recall that the gain for a non inverting amplifier is: Gain = 1 + Rf/ kΩ ...
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In this case, the output signal should be twice the amplitude of the input signal kΩ and kΩ, the gain will be: Gain = 1 + 2000/1000 ...
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Understanding Signals - OPAmpExamplewithFREQOUT.bs2 ' Generate a sine wave for the op-amp '{$STAMP BS2} '{$PBASIC 2.5} DO FREQOUT 15, 1000, 1000 LOOP Keep in mind that the amplifier gain for kΩ and kΩ ...
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You will repeat this exercise using different resistor values for Ri and Rf to create a gain of 2 and a gain of 3. When you repeat this exercise for a gain of 2, where kΩ and ...
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When you up the gain kΩ and kΩ) your signal will most likely be heavily clipped, as shown in Figure 8-13. We won’t calculate the gain, but the signal is worth examining ...
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How healthy is your battery? We measured the clipped signals for 3 different 9 V batteries, and had readings of 8.01 V, 7.29 V and a low of 6.53 V, shown in Figure 8-13. ACTIVITY #2: INVERTING AMPLIFIER WITH ADJUSTABLE ...
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Negative voltages can be viewed by applying a negative Vee with a separate power supply. This is most easily done with a second 9 V battery. Disconnect the op-amp’s Vee from the Vss on your Board of ...
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P15 10 Pot 1 µF Vss Vdd X3 P15 P14 P13 P12 P11 P10 √ Once the circuit is built, connect the probes of the ...
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Re-run the program OPAmpExamplewithFREQOUT.bs2. √ Adjust the tap on the potentiometer by gently twisting the knob until the entire signal is visible and no longer clipped Figure 8-16 . Notice that output signal is a mirror image ...
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Summary This chapter introduced just a few basic examples of the many uses of operational amplifiers: buffers, and inverting and non-inverting voltage amplifiers. The concepts of gain, slew rate, and signal clipping were introduced. A variable resistor was used to ...
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Appendix A: System and Equipment Requirements SYSTEM REQUIREMENTS The software operating the OPTAscope must run on an IBM style PC. Additionally, the following list of minimum requirements must be met: √ Pentium (or equivalent) running @ 233MHz √ Microsoft Windows ...
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... Fresh 9 V battery (not included). UNDERSTANDING SIGNALS KIT Understanding Signals Bill of Materials Parallax Part # Description 70009 Understanding Signals Student Guide, Version 1.0 28014 OPTAscope, three probes, USB cable, and CD-ROM 900-00005 Parallax Standard Servo 451-00303 3-pin headers m/m ...
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Appendix B: OPTAscope 81M Specifications OPTASCOPE 81M SPECIFICATIONS • 2 Channels • 1 Ms/s max. sample rate with one channel, 500 Ks/s with two channels • View kHz sine wave 100 kHz square wave • ...
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Index - A - A/D converter, 65 active channel, 8 amplitude, 41, 43, 47, 107, 108, 109 asynchronous data, 65 asynchronous serial communication, 73 attenuation, 44, 103, 105 automatic measurements, 13 Automatic Measurements display, 10 Autoscale, 90 Autoscale button, 12, ...
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10, 78 false triggering, 90 Fast Fourier Transformation FFT Files/Settings tab, 10 Floating cursors, 12 Fourier analysis, 45 FREQOUT, 38, 40, 43, 86, 105, 108 frequency, 2, 10, 13, 35, 38, 43 ...
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P - Pan mode, 12 parallel data transmission, 65 phase shift, 44 Plot Area Plot Area Indicator bar, 9 Position Cursor buttons, 12 Print button, 10 Print Preview button, 10 pulse train, 35, 90, 95 pulse width ...
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Trigger Edge switch, 11 Trigger Mode switch, 11 trigger position, 9 Trigger Settings display, 10 Trigger Source switch, 11 Trigger tab, 11 Trigger Edge switch, 11 trigger event falling edge, 18 rising edge, 18 trigger events, 3 falling edge, 3 ...
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