Agilent 4000 X-Series Oscilloscopes Advanced Training Guide Lab guide and tutorial for making advanced oscilloscope measurements using an Agilent 4000 X- Series oscilloscope with the DSOXEDK training kit.
Notices © Agilent Technologies, Inc. 2008-2012 Manual Part Number The copyright on this instructional material grants you permission to reprint, modify, and distribute in whole or in part the document for the purpose of training on Agilent test equipment. 54702-97011 Edition November, 2012 Available in electronic format only Trademarks Microsoft®, MS-DOS®, Windows®, Windows 2000®, and Windows XP® are U.S. registered trademarks of Microsoft Corporation.
Contents 1 Getting Started Lab Guide—At a Glance 5 Front Panel Overview 6 Run Control 7 Waveform Controls 7 Horizontal Controls 8 Vertical Controls 9 Trigger Controls 9 Tools Controls 10 2 Oscilloscope Familiarization Labs Lab #1: Using Cursors and Automatic Parametric Measurements Lab #2: Using Zoom Display to Perform Gated Measurements Lab #3: Using Waveform Math 19 23 Lab #4: Using Peak Detect Acquisition Mode 27 Lab #5: Using Segmented Memory Acquisition Mode Lab #6: Using Mask Test 12 31 37
Lab #16: Decoding, Triggering, and Searching on SPI Serial Bus Signals 87 Lab #17: Decoding, Triggering, and Searching on RS232/UART Serial Bus Signals Lab #18: Decoding, Triggering, and Searching on CAN Serial Bus Signals 102 Lab #19: Decoding, Triggering, and Searching on LIN Serial Bus Signals 110 Lab #20: Decoding, Triggering, and Searching on I2S Serial Bus Signals 118 Lab #21: Decoding, Triggering, and Searching on FlexRay Serial Bus Signals 125 Lab #22: Decoding, Triggering, and Searching o
Agilent 4000 X-Series Oscilloscopes Advanced Training Guide 1 Getting Started Lab Guide—At a Glance 5 Front Panel Overview 6 Lab Guide—At a Glance This advanced oscilloscope training guide and tutorial is intended to be used with Agilent Technologies InfiniiVision 4000 X- Series oscilloscopes (DSO and MSO models) that are licensed with the Oscilloscope Education Training Kit (DSOXEDK).
1 Getting Started If you not familiar with the Agilent InfiniiVision 4000 X- Series oscilloscope, first look over the main sections of the front panel as illustrated on the following pages, and then begin with Chapter 2, “Oscilloscope Familiarization Labs,” starting on page 11. Once you have become familiar with using the basic functions of the oscilloscope, you can then skip to particular labs of interest.
Getting Started 1 Run Control When the oscilloscope is turned on, or if [Auto Scale] is pressed, the acquisition will be set to [Run]. At any time you may [Stop] the acquisition process to examine a signal in detail or to save it. • The [Default Setup] key on the front panel sets the oscilloscope to the default configuration.
1 Getting Started • The [Intensity] key and the signal brightness. Entry knob lets you set the desired Horizontal Controls a Turn the large knob in the Horizontal control section clockwise and counter- clockwise to control the time/div setting of the horizontal axis. Observe the changes in the displayed signal. The current timebase setting is displayed at the top of the display on the status line.
Getting Started 1 Vertical Controls • Turn the large knobs in the Vertical section to control the V/div setting for each analog channel. The V/div setting is displayed in the upper left hand corner of the status line at the top of the display. Color coding matches analog channel inputs, vertical control knobs, and waveform colors. • Press the [1] key to display the channel 1 menu. Press again to turn the channel on and off.
1 Getting Started • Press the [Mode/Coupling] key in the Trigger controls section to view the Trigger Mode and Coupling Menu selections and to set trigger holdoff. • Press and hold the Mode softkey to read the built- in help about the Auto and Normal trigger modes. Tools Controls • Press the [Utility] key to access the I/O ports, file explorer, options, service information, and the “Quick Action” key function settings.
Agilent 4000 X-Series Oscilloscopes Advanced Training Guide 2 Oscilloscope Familiarization Labs Lab #1: Using Cursors and Automatic Parametric Measurements 12 Lab #2: Using Zoom Display to Perform Gated Measurements 19 Lab #3: Using Waveform Math 23 Lab #4: Using Peak Detect Acquisition Mode 27 Lab #5: Using Segmented Memory Acquisition Mode 31 Lab #6: Using Mask Test 37 s1 11
2 Oscilloscope Familiarization Labs Lab #1: Using Cursors and Automatic Parametric Measurements During this first hands- on lab, you will learn how to make simple voltage and timing measurements using the scope’s manually positioned measurement cursors, as well as perform similar measurements using the scope’s automatic parametric measurement capability. 1 Connect the channel- 1 probe to the Demo 1 terminal and ground. 2 Press [Default Setup] on the scope’s front panel.
Oscilloscope Familiarization Labs 2 At this point, you should see a repetitive digital pulse with overshoot and ringing similar to what is shown in Figure 1. Note that all front panel knobs are pushable. If you push the V/div knob or time/div knob, you can toggle between course adjustment and fine adjustment (vernier control). When other knobs are pushed, the scope will pre- set conditions associated with that particular knob.
2 Oscilloscope Familiarization Labs Figure 3 Using the scope’s cursor measurements. Delta readouts are displayed on the right- hand side of the display. If you the press the [Cursors] front panel key, you can see absolute voltage and time readouts for each cursor near the bottom of the display. Your screen should now look similar to Figure 3.
2 Oscilloscope Familiarization Labs 16 Notice the level indicator that shows where this measurement is being performed. 17 Press the Type softkey; then select Minimum. Figure 4 The scope automatically performs up to four parametric measurements. Your scope’s display should now look similar to Figure 4 showing four continuously update measurements; Frequency, Vp- p, Vmax, and Vmin. Let’s now perform four different measurements. 18 Set the scope’s timebase to 200.0 ns/div.
2 Oscilloscope Familiarization Labs Figure 5 Performing additional pulse parameter measurements on a digital pulse. Your scope’s display should now look similar to Figure 5. If Fall Time was the last measurement that you selected, then the cursors will show where this measurement is being performed.
Oscilloscope Familiarization Labs 2 absolute voltage levels, such as from/to ± 1.0 V. Let’s now set up our scope to measure just the rise time of this pulse relative to the 20% and 80% threshold levels. 20 Press the Clear Meas softkey; then press the Clear All softkey. 21 Press the Settings softkey; then press the Thresholds softkey. 22 Press the Lower softkey; set the value to 20%. 23 Press the Upper softkey; set the value to 80%.
2 Oscilloscope Familiarization Labs measurement should now read approximately 30 ns. When we used the scope’s default 10%/90% threshold levels, the measurement should have read approximately 40 ns. Let’s now make one more measurement before completing this lab. But this time let’s perform a more comprehensive set of measurements on this waveform. 27 Set the scope’s timebase to 500.0 ns/div. 28 Press the Type softkey; select Snapshot All (top of the list).
Oscilloscope Familiarization Labs 2 Lab #2: Using Zoom Display to Perform Gated Measurements When performing automatic parametric measurements, such as positive pulse width measurements, on an exactly repetitive input signal, such as a simple sine wave or square wave, it really doesn’t matter which particular pulse the scope chooses to make the measurement on; each pulse is the same.
2 Oscilloscope Familiarization Labs Figure 8 Setting up the oscilloscope to capture a burst of digital pulses with different pulse widths. You should now observe 6 positive pulses with varying widths, plus an infrequent glitch occurring after the 6th pulse as shown in Figure 8. Let’s now turn on a “+ Width” measurement. 11 Press the [Meas] front panel key (next to the Cursors knob). 12 Press the Clear Meas softkey; then press the Clear All softkey.
2 Oscilloscope Familiarization Labs Figure 9 Measuring the positive pulse width of the 1st pulse in the burst. The scope always performs measurements on the pulse located closest to center- screen. In this case, the scope measures the positive pulse width of the 1st pulse in this digital burst as shown in Figure 9. But what if we want to know the widths of the 2nd, 3rd, 4th, etc., pulses? 15 Press the button in the Horizontal section of the front panel to turn on the scope’s “zoom” display mode.
2 Oscilloscope Familiarization Labs Figure 10 Using the scope’s Zoom timebase mode to perform “gated” measurements. You should now see on your scope’s display an expansion of just the 3rd pulse in this burst in the lower portion of the display as should in Figure 10. And the + Width measurement should be measuring the positive pulse width of just the 3rd pulse.
Oscilloscope Familiarization Labs 2 Lab #3: Using Waveform Math In addition to performing automatic parametric measurements on waveform data, the oscilloscope can also perform math operations on an entire waveform or pair of waveforms. One very common waveform math function that you may want the scope to perform is to subtract one waveform from another.
2 Oscilloscope Familiarization Labs Figure 11 Using waveform math to subtract channel-2 from channel-1. You should now see three waveforms on your scope’s display as shown in Figure 11. The purple waveform is the result of the scope’s math function of subtracting the channel- 2 waveform from the channel- 1 waveform. Note that to change the scaling of the math waveform, you can use the knobs on the right- hand side of the scope’s front panel near the [Math] key.
Oscilloscope Familiarization Labs 2 16 Select the Clock with Infrequent Glitch signal and press the Output softkey to turn it on. 17 Set channel- 1’s V/div setting to 500 mV/div. 18 Set channel- 1’s offset to approximately 1.00 V in order to center the waveform on- screen. 19 Push the trigger level knob to set the trigger level at approximately 50%. 20 Set the timebase to 20.0 µs/div.
2 Oscilloscope Familiarization Labs signal that has a 50% duty cycle should consist of a fundamental sine wave frequency component (signal’s repetitive frequency), plus its odd harmonics (3rd, 5th, 7th, etc.). Note that non- ideal square waves will also include lower- level even harmonics. Let’s now verify the frequencies of the fundamental and odd harmonics. 23 Press the [Cursors] front panel key (near the Cursors knob).
Oscilloscope Familiarization Labs 2 Lab #4: Using Peak Detect Acquisition Mode All DSOs and MSOs have a fixed amount of acquisition memory. This is the number of samples that the oscilloscope can digitize for each acquisition cycle. If the scope’s timebase is set to a relatively fast time/div setting, such as 20 ns/div, then the scope will always have a sufficient amount of memory to capture a waveform at that setting using the scope’s maximum specified sample rate.
2 Oscilloscope Familiarization Labs Figure 13 The scope’s automatically-reduced sample rate under-samples the repetitive glitch. At this point, you should see a sine wave similar to Figure 13. But if you look closely you should also see some glitches (narrow pulses) near the peaks of this sine wave. And the amplitude of these glitches may appear to vary (bouncing up and down). The amplitude of these glitches is actually very stable.
2 Oscilloscope Familiarization Labs Figure 14 The Peak Detect acquisition mode reliably captures the narrow glitches riding on the slow sine wave. The height of the glitches should now appear much more stable as shown in Figure 14. When the Peak Detect acquisition mode has been selected, rather than sampling waveforms at a reduced rate, the scope intelligently decimates acquired data at a higher sample rate.
2 Oscilloscope Familiarization Labs To learn more about oscilloscope real- time sampling, refer to Agilent’s Application Note titled, “Evaluating Oscilloscope Sample Rates vs Sampling Fidelity” listed in "Related Agilent Literature" on page 165.
Oscilloscope Familiarization Labs 2 Lab #5: Using Segmented Memory Acquisition Mode All oscilloscopes have a limited amount of acquisition memory. The amount of acquisition memory that your scope has will determine the length of time it can capture while still using a fast sampling rate. You can always capture a long time span by simply setting the timebase to a long time/div setting.
2 Oscilloscope Familiarization Labs Figure 15 Capturing and displaying an RF burst at 200.0 ns/div. You should see a single burst of sine waves similar to what is shown in Figure 15. Let’s now rescale the timebase in an attempt to capture several of these bursts. 9 Set the scope’s timebase to 10.000 ms/div.
Oscilloscope Familiarization Labs 2 Figure 16 Capturing multiple RF burst waveforms at a slower timebase setting. When we attempt to capture multiple RF bursts that are separated by 4.0 ms, the scope under- samples and shows varying amplitudes of the signal as shown in Figure 16. Again, this is because the scope automatically reduced its sample rate in order to capture a longer time- span with its limited amount of acquisition memory. Let’s now zoom- in and take a closer look at this under- sampled data.
2 Oscilloscope Familiarization Labs Figure 17 Zooming in reveals an under-sampled waveform. After acquiring the waveform at the slower timebase setting, and then zooming in, we can clearly see that our waveform was under- sampled as evidenced by the triangular shaped waveforms shown in Figure 17. Remember, this should be a burst of sine waves.
Oscilloscope Familiarization Labs 2 16 Press the Current Seg softkey; then turn the Entry knob to review all 500 waveforms. 17 Now set the Current Seg = 500 using the Entry knob (last captured segment/waveform). Figure 18 Using Segmented Memory Acquisition to capture more waveforms with high resolution.
2 Oscilloscope Familiarization Labs unimportant signal idle- time between each burst. Segmented Memory acquisition can also be a very useful tool for capturing multiple serial packets of digital data, which will be demonstrated in Chapter 4, “Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs,” starting on page 79.
Oscilloscope Familiarization Labs 2 Lab #6: Using Mask Test With mask testing you can set up a pass/fail test criteria for automatically testing waveforms to see if they conform to specific wave shapes. In this lab we will test a digital signal that includes an infrequent glitch. With InfiniiVision’s hardware- based mask testing capability, we will be able to test over 200,000 waveforms per second and gain insight into the statistical occurrences of this particular glitch.
2 Oscilloscope Familiarization Labs Figure 19 The scope’s fast waveform update rate easily captures an infrequent glitch. At this point, you should be able to see that the scope is capturing an infrequent glitch as shown in Figure 19. This particular glitch occurs just once every 1,000,000 cycles of the clock signal that we are triggering on. Because this scope can update waveforms as fast as 1,000,000 waveforms/sec, the scope can capture the glitch on average once per second.
Oscilloscope Familiarization Labs 2 Figure 20 Mask Testing provides us within detailed statistics about the rate of occurrence of the infrequent glitch. Because the InfiniiVision oscilloscope’s mask testing capability is hardware- based, it can test over 200,000 waveforms/sec and provide detailed pass/fail statistics including failure rate in terms of both percent and a Sigma quality factor as shown in Figure 20.
2 Oscilloscope Familiarization Labs Figure 21 Establishing specific test criteria. In addition to stopping acquisitions when an error is detected as shown in Figure 21, you can also save a waveform, save an image, print, or perform specific measurements when an error is detected. Using the “Run Until” selection, you can also set up mask testing to run for a specific number of tests, minimum time, or minimum Sigma test criteria.
Agilent 4000 X-Series Oscilloscopes Advanced Training Guide 3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #7: Triggering on a Digital Burst using Trigger Holdoff 42 Lab #8: Triggering on Unique Pulses and Glitches using “Pulse-width” Trigger 46 Lab #9: Triggering on the Nth Pulse within a Burst using “Nth Edge Burst” Trigger 51 Lab #10: Triggering on and Searching for Edge Speed Violations 53 Lab #11: Triggering on and Searching for Runt Pulses 60 Lab #12: Triggering on Set
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #7: Triggering on a Digital Burst using Trigger Holdoff Signals in the real world of electronics are rarely as simple as repetitive sine waves and square waves. Establishing unique trigger points on more complex signals sometimes requires using trigger “hold- off”. In this lab you will learn how to use the scope’s trigger hold- off capability in order to trigger on a burst of digital pulses.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 You should see on your scope’s display what may appear to be an un- triggered display of a series of digital pulses similar to Figure 22. The scope is actually triggering on random rising edge crossings of this complex digital data stream, which is actually a “burst” of pulses. Unfortunately we can’t “see” the burst activity because we haven’t yet set up the scope to establish a unique trigger point on this complex signal.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Estimate or use the scope’s timing cursors (X1 & X2) to measure the width of one of the burst of pulses, and also measure the time from the beginning of one burst of pulses to the beginning of the next burst of pulses. You should find that the width of each burst is approximately 40 µs, and the time between bursts is approximately 50 µs.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Trigger Point 3 Holdoff Time Next Valid Trigger Event Figure 24 Using the scope’s trigger holdoff feature to synchronize on a burst of pulses. You should now see a synchronized display as shown in Figure 24. The scope triggers on the 1st edge of a burst of pulses (center- screen) and then disables triggering for 45.00 µs (holdoff time). During this holdoff time, the scope ignores the 2nd, 3rd, 4th, etc.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #8: Triggering on Unique Pulses and Glitches using “Pulse-width” Trigger In this lab you will learn how to use the scope’s Pulse Width triggering mode to trigger on pulses within a digital data stream that have unique pulse widths, including an infrequently occurring glitch. 1 Connect the channel- 1 probe to the Demo 1 terminal and ground. 2 Press [Default Setup] on the scope’s front panel.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs You should now see on your scope’s display a digital burst waveform consisting of six pulses of various widths, followed by an infrequent glitch similar to Figure 25. Using the scope’s default Edge triggering mode, the scope usually triggers on the 1st pulse of this burst. But if you increase the scope’s waveform intensity to 100%, you will see that the scope sometimes triggers on later pulses within this burst.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 26 Triggering on a 300 ns wide pulse using the scope’s Pulse Width triggering mode. Your scope should now be triggering at the end of the 5th pulse of the burst as shown in Figure 26. This particular pulse uniquely meets the pulse width time qualification of > 250 ns, but < 350 ns. You can select the +Width measurement if you would like to verify that this pulse has an approximate width of 300 ns.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Figure 27 Triggering on a narrow infrequent glitch using the scope’s Pulse Width triggering mode. Your scope should now be triggering on the narrow infrequent glitch that follows the repetitive burst of six pulses as shown in Figure 27. Note that if this glitch was more infrequent, you would also need to select the Normal trigger mode to avoid auto triggering.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 21 Set the Current Segment to 500 and note the time- tag of the last captured segment. Figure 28 Using the scope’s Segmented Memory acquisition to selectively capture 500 consecutive occurrences of a burst of pulses. Segmented Memory optimizes oscilloscope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #9: Triggering on the Nth Pulse within a Burst using “Nth Edge Burst” Trigger In this lab you will learn how to use the scope’s “Nth Edge Burst” triggering mode to trigger on pulses within a burst based on pulse count. Note that we will be using the same training signal that we used in the previous lab. 1 Connect the channel- 1 probe to the Demo 1 terminal and ground. 2 Press [Default Setup] on the scope’s front panel.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs You should now see on your scope’s display a digital burst waveform consisting of six pulses of various widths, followed by an infrequent glitch similar to Figure 29. Using the scope’s default Edge triggering mode, the scope usually triggers on the 1st pulse of this burst. Let’s now set up the scope to trigger on the 3rd pulse in this burst using the “Nth Edge Burst” triggering mode.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Lab #10: Triggering on and Searching for Edge Speed Violations In this lab you will learn how to set up the scope to trigger on edge speed violation conditions using the scope’s “Rise/Fall Time” trigger mode.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 31 Scope display reveals two different rising edge speeds when triggering on any rising edge. Your scope’s display should now look similar to Figure 31. Using the scope’s default rising edge type trigger, we can see two distinctly different rising edge speeds on this waveform. Also notice that the slower transitioning edge appears dimmer.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Figure 32 The scope’s measurement statistics shows the range of rising edge speeds on this signal. Looking at the on- screen Rise Time measurement statistics, we can see that the scope is measuring a minimum Rise Time in the range of 50 ns, while also measuring a maximum Rise Time in the range of 125 ns as shown in Figure 32.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 14 Press the Level Select softkey until it indicates High; then turn the Trigger Level knob to set the upper (high) trigger threshold level to the approximate 90% level. Note that you can also drag the TH marker on the left side of the display. 15 Tap the “< >” softkey to select “>”. 16 Tap the Time softkey twice, which opens the keypad. Set the violation time to > 100 ns.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 21 Tap the Settings softkey. 22 Tap the “< >” softkey; the select “>”. 23 Press the Time softkey; enter in > 100 ns. Figure 34 The scope automatically finds several rise time violation edges. At this timebase setting (200 µs/div), the scope captured over a thousand edges of this signal.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Press the mode. (zoom) front key to turn off the scope’s horizontal zoom 26 Push the horizontal position/delay knob to re- position the trigger point back to center- screen. 27 Set the scope’s timebase to 100.0 ns/div. 28 Press the [Run/Stop] front panel to begin repetitive acquisition again. 29 Press the [Acquire] front panel key. 30 Tap the Segmented softkey; set 500 as the number of segments to capture.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Segmented Memory optimizes oscilloscope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting. In this example, we have selectively captured 500 occurrences of this signal that has a rise time violation for a total acquisition time of nearly 100 ms.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #11: Triggering on and Searching for Runt Pulses A “runt” pulse is defined as either a positive or negative digital pulse that fails to meet a minimum required amplitude. In this lab you will learn how to set up the scope to trigger on runt pulse conditions.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Figure 36 Scope display reveals various amplitude pulses while triggering on any rising edge. Your scope’s display should now look similar to Figure 36. Using the scope’s default rising edge type trigger, we can see pulses that have various amplitudes. The pulses that have the lower amplitudes are “runt” pulses.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 37 Triggering on positive runts. Your scope should now be triggering on positive runt pulses of two different widths as shown in Figure 37. Note that as shown in previous labs, the high and low trigger levels can be set using the touchscreen with the TL and TH markers to the left of the display.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Figure 38 Triggering on a positive runt pulse that is < 200 ns wide. Your scope’s display should look similar to Figure 38 showing a positive runt pulse that is approximately 100 ns wide near center- screen. In addition to triggering on runt pulse conditions, the Agilent 4000 X- Series oscilloscopes can also perform Search & Navigation to find multiple runt pulse conditions, regardless of the specific trigger setup condition.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 39 Automatic “Search” finds and marks multiple runt pulses. Your scope’s display should now look similar to Figure 39. The white triangle marks at the top of the display indicate the location of each positive runt pulse that the scope found. Let’s now set up the scope to automatically navigate to each “found” runt. 20 Press the (zoom) front panel key to turn on the scope’s horizontal zoom mode.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 26 Press the [Trigger] front panel key. 27 Press the “runt polarity” softkey and select the “either polarity” (third) icon. 28 Tap the Qualifier softkey to select None. 29 Press the [Acquire] front panel key. 30 Tap the Segmented softkey; then double- tap # of Segs to enter 500 as the number of segments to capture. 31 Tap the Segmented softkey to begin a Segmented Memory acquisition.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #12: Triggering on Setup & Hold Time Violations In this lab we will set up the scope to trigger on a Setup & Hold time violation. We will also use the scope’s Segmented Memory acquisition to capture multiple and consecutive occurrences of Setup & Hold time violations. 1 Connect the channel- 1 probe to the Demo 1 terminal and ground. 2 Connect the channel- 2 probe to the Demo 2 terminal and ground.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 presented in an eye- diagram format. When clocking data into a memory device, if the data signal is going to change polarity (high- to- low or low- to- high), then it must switch polarities a minimum amount of time before the occurrence of the clocking signal. This is commonly referred to as the device’s minimum specified “setup” time.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 42 Triggering the scope on just setup time violations of less than 25 ns. Your scope should now be triggering on just setup time violation conditions similar to Figure 42. With this unique trigger condition, perhaps we can now correlate these signals to other signals and/or activity in our system that may be producing this timing problem.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Figure 43 Using the scope’s Segmented Memory acquisition to selectively capture 500 consecutive occurrences of a setup time violationrunt pulses. Segmented Memory optimizes oscilloscope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #13: Triggering on a Qualified Burst using “Edge then Edge” Trigger In this lab you will learn how to use the scope’s “Edge then Edge” trigger mode. This trigger mode is sometimes referred to as “qualified A then B” triggering. “Edge then Edge” triggering allows you to qualify triggering on an edge of any channel, then delay arming of the final trigger condition by both time and event count of an edge of any channel.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 44 Capturing a complex burst signal while triggering on a synchronization signal. Your scope’s display should now look similar to Figure 44 while using the scope’s default trigger condition (rising edge of channel- 1). Let’s now set up the scope to trigger on one of the wider digital pulses on channel- 2.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 45 Using Edge then Edge triggering to synchronize acquisitions on the 3rd digital pulse of channel-2. Your scope’s triggering should now be synchronized on the 3rd digital pulse on channel- 2 after qualifying on the channel- 1 pulse, and after delaying past the higher frequency analog burst as shown in Figure 45.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #14: Triggering on Logic Patterns using the MSO’s Digital Channels In this lab you will learn how to use the scope’s digital channels of acquisition (MSO), and then set up the scope to trigger on a specific Boolean pattern combination. Note that to complete this lab your scope must either be an MSO model, or a DSO model that has been upgraded with the MSO option (Option MSO).
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs You should now see on your scope’s display a stair- step sine wave on channel- 1 plus eight digital waveforms captured by the D0 through D7 digital channels of acquisition similar to Figure 46. D0 through D7 are the input signals to an digital- to- analog converter (DAC), while the stair- step sine wave is the output of the DAC. At this point, you may be wondering where these digital signals are coming from.
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 3 Figure 47 Triggering on Pattern = 1110 0110. Your scope should now be triggering on logic pattern 1110 0110 (D7- D0), and the top of the sine wave should be centered on- screen as shown in Figure 47. In addition to displaying individual digital channels, this scope can also display all of the digital channels of acquisition in an overlaid bus display mode while displaying the HEX value of the bus.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 48 Displaying digital channels in a “bus” display mode. You should now see a “bus” display mode showing HEX values of the D7- D0 bus at the bottom of the scope’s display similar to Figure 48. Note that it addition to specifying a pattern trigger condition in a binary format, we can also specify to trigger on a pattern condition as a HEX value.
3 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 49 Triggering on pattern = 1AHEX. Your scope should now be triggering on 1AHEX, which is coincident with the lowest output level of DAC, as shown in Figure 49.
3 78 Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs 4000 X-Series Oscilloscopes Advanced Training Guide
Agilent 4000 X-Series Oscilloscopes Advanced Training Guide 4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #15: Decoding, Triggering, and Searching on I2C Serial Bus Signals 80 Lab #16: Decoding, Triggering, and Searching on SPI Serial Bus Signals 87 Lab #17: Decoding, Triggering, and Searching on RS232/UART Serial Bus Signals 94 Lab #18: Decoding, Triggering, and Searching on CAN Serial Bus Signals 102 Lab #19: Decoding, Triggering, and Searching on LIN Serial
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #15: Decoding, Triggering, and Searching on I2C Serial Bus Signals In this lab you will learn how to set up the scope to decode and trigger on I2C serial bus traffic. In addition, you will learn how to use the scope’s automatic I2C Search & Navigation capability, as well as use Segmented Memory acquisition to capture multiple and consecutive occurrences of a particular Read operation.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 50 Capturing I2C clock and data while triggering on an edge of the clock (channel-1). You should see on your scope’s display what appears to be an un- triggered display of two digital signals similar to Figure 50. Your scope is actually triggering on random rising edges of channel- 1, which is the scope’s default trigger condition.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 17 Tap the Lister softkey; then select Window and tap Half-Screen to show a list of Serial 1 (I2C). Figure 51 Decoding I2C serial bus traffic. Your scope should now be decoding I2C serial bus traffic as shown in Figure 51. We can see automatic decoding of this I2C bus in two formats.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Note that your scope should still be triggering on random edge crossings of channel- 1. Let’s now set up the scope to trigger when it detects a Read operation from address = 29HEX, following by an “acknowledge”, followed by any data content (don’t care). 18 Press the [Trigger] front panel key; then select Serial 1 (I2C) using the Entry knob.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs This particular frame should be interpreted as a Read (R) operation from address 29 with an acknowledge (A), followed by a data byte equal to FF with an acknowledge (A), following by a data byte equal to either 80 or C0 without an acknowledge (~A). Let’s now capture a very long stream of I2C data and then manually search through the captured and decoded record. 22 Set the scope’s timebase to 20.00 ms/div.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 53 Automatic Search & Navigation. The white triangles near the top of the waveform area mark the time location of each “found” occurrence of our search operation as shown in Figure 53. These frames are also marked in orange in the first/pointer column of the lister table. Your scope should have found and marked approximately 25 occurrences of this search operation based on a total acquisition time of 200 ms.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 35 Tap the Segmented softkey; double- tap on # of Segs and set the value to 500. 36 Press the Segmented softkey to begin a Segmented Memory acquisition. 37 Tap the Current Segment softkey; then turn the Entry knob to review all 500 captured segments. 38 Set the Current Segment to 500 and note the time- tag of the last captured segment.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #16: Decoding, Triggering, and Searching on SPI Serial Bus Signals In this lab you will learn how to set up the scope to decode and trigger on 4- wire SPI serial bus traffic. In addition, you will learn how to use the scope’s automatic SPI Search & Navigation capability, as well as use Segmented Memory acquisition to capture multiple and consecutive occurrences of a particular serial byte.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 55 Capturing 4-wire SPI signals using the scope’s digital channels of acquisition (MSO). You should now see four digital waveforms captured by the scope’s digital channels of acquisition similar to Figure 55. These SPI training signals are being generated by the scope’s built- in pattern generator and routed directly to the scope’s digital acquisition system; bypassing the logic probe.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 15 Tap the Clock softkey twice to open the menu; then double- tap D7 to set it as as the clock source. 16 Press the Back (Back) front panel button to return to the previous menu. 17 Tap the MOSI softkey; then select D9. 18 Press the Back (Back) front panel button to return to the previous menu. 19 Tap the MISO softkey; then select D8. 20 Press the Back (Back) front panel button to return to the previous menu.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 24 Tap the Trigger Setup softkey. 25 Tap the Bit softkey and enter 0 in the keypad. 26 Tap the 0 1 X softkey to select 0 as the trigger logic condition for Bit 0 (MSB). 27 Tap the Bit softkey and enter 1 in the keypad. 28 Tap the 0 1 X softkey to select 0 for Bit 1. 29 Repeat Steps #27 and #28 until MOSI Data = 0000 0011. Figure 57 Triggering on MOSI data = 03HEX.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 34 Tap the Scroll Lister softkey; then turn the Entry knob to manually scroll through the lister table. You can also scroll using the scroll bar on the right of the lister window. As you scroll through the data, note that waveforms “track”. This means that the frame that the arrow points to in the lister table corresponds to the waveforms that are positioned at center- screen.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 58 Automatic Search & Navigation on SPI traffic. The white triangles near the top of the waveform area mark the time location of each “found” occurrence of our search operation as shown in Figure 58. These frames are also marked in orange in the first/pointer column of the lister table.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 48 Tap the Segmented softkey; then tap # of Segs and enter 500 as the number of segments to capture. 49 Tap the Segmented softkey to begin a Segmented Memory acquisition. 50 Tap the Current Segment softkey; then turn the Entry knob to review all 500 captured segments. 51 Set the Current Segment to 500 and note the time- tag of the last captured segment.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #17: Decoding, Triggering, and Searching on RS232/UART Serial Bus Signals In this lab you will learn how to set up the scope to decode and trigger on transmit and receive RS232/UART serial bus traffic. In addition, you will learn how to use the scope’s automatic RS232/UART Search & Navigation capability, as well as Segmented Memory acquisition.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 60 Capturing RS232/UART transmit and receive data signals using the scope’s Edge triggering mode. You should now see on your scope’s display what appears to be an un- triggered display of two digital signals similar to Figure 60. Your scope is actually triggering on random rising edges of channel- 1, which is the scope’s default trigger condition.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 18 Tap the Parity softkey; then select Odd. 19 While this menu is active, also verity that the # of Bits is set to 8, the Baud Rate is set to 19.2 kb/s, Polarity is set to Idle Low, and Bit Order is set to LSB first. 20 Press the [Label] front panel key (between channel- 1 and channel- 2 controls) to turn on the scope’s default labels. Figure 61 Decoding the RS232/UART serial bus.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 62 Triggering on Tx = 4DHEX. Your scope should now be triggering on Tx = 4DHEX while displaying this byte at center- screen similar to Figure 62. Let’s now set up the scope to capture a longer record of time (2 seconds) and review our data in a “lister” format. 25 Set the scope’s timebase to 200.0 ms/div. 26 Press [Run/Stop] to stop repetitive acquisitions. 27 Press the [Serial] front panel key.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs automatic search to find every occurrence of parity bit errors on both the Tx and Rx data lines. We will then automatically navigate to each of these occurrences. 30 Push the horizontal position/delay knob to re- position the trigger point back to center- screen. 31 Set the scope’s timebase to 200.0 ms/div. 32 Press the [Search] front panel key. 33 Tap the Search Edge softkey; then select Serial 1 (UART/RS232).
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Let’s now set up the scope to trigger exclusively on parity errors. But because these errors occur so infrequently, we will need to change the trigger mode from Auto to Normal to prevent auto triggering. 35 Push the horizontal position/delay knob to re- position the trigger point back to center- screen. 36 Set the scope’s timebase to 1.00 ms/div.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs parity errors. We will then review the captured errors to determine how often they occur. But to complete the rest of this lab your scope must be licensed with the Segmented Memory option. 43 Press the [Acquire] front panel key. 44 Tap the Segmented softkey; then enter 50 on the keypad as the number of segments to capture.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Note that although not shown and demonstrated, we can also view the segmented decoded RS232/UART serial data in the “lister” format, and we can also perform Search & Navigation on the segments. Let’s now view this decoded RS232/UART in a different numeric format to uncover a important Agilent marketing message.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #18: Decoding, Triggering, and Searching on CAN Serial Bus Signals In this lab you will learn how to set up the scope to decode and trigger on a CAN serial bus signal. In addition, you will learn how to use the scope’s automatic CAN Search & Navigation capability, as well as Segmented Memory acquisition. This lab does not provide a tutorial on the CAN protocol and signaling.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 67 Capturing a CAN frame using the scope’s Edge triggering mode. You should now see on your scope’s display what appears to be an un- triggered display of a digital burst signal similar to Figure 67. Your scope is actually triggering on random rising edges of channel- 1, which is the scope’s default trigger condition.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 68 Decoding a CAN bus while triggering on any rising edge of the input signal. You should now see CAN decoding of this signal on your scope’s display similar to Figure 68, but we still haven’t established stable triggering. The scope is still triggering on any rising edge of channel- 1 (default trigger condition). Let’s now set up the scope to trigger on a CAN data frame with the ID = 07FHEX.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 69 While triggering on CAN data frame = 07FHEX, the scope’s hardware-based decoding reveals infrequent error conditions. Your scope should now be triggering on CAN data frame = 07FHEX as shown in Figure 69. With this scope’s very fast hardware- based decoding, you should also see some decoded red “flashing” near the end of this packet/frame of data.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs decoded record can be difficult. So let’s now perform an automatic search to find all occurrences of Error Frames and “form” errors (non- flagged error conditions). We will then automatically navigate to each of these error conditions. 23 Push the horizontal position/delay knob to re- position the trigger point back to center- screen. 24 Set the scope’s timebase to 100.0 ms/div. 25 Press the [Search] front panel key.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 time of 1 second. Note that the number of “found” events is indicated near the bottom of the display. To automatically navigate to each CAN error, press the and front panel navigation keys. Let’s now use the scope’s Segmented Memory mode of acquisition to capture 100 consecutive occurrences of CAN error conditions. But to complete the rest of this lab your scope must be licensed with the Segmented Memory option.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 71 Using the scope’s Segmented Memory acquisition to selectively capture 100 CAN error conditions. Segmented Memory optimizes oscilloscope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting. In this example, we have selectively captured approximately 10 seconds of total acquisition time as shown in Figure 71.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 72 Lister display shows errors in every frame from a Segmented Memory acquisition based on triggering on “All Errors”. Because we performed the Segmented Memory acquisition based on triggering on any “form” or flagged “error frame” condition (All Errors), our Lister display now shows that every captured frame contains some type of error as shown in Figure 72.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #19: Decoding, Triggering, and Searching on LIN Serial Bus Signals In this lab you will learn how to set up the scope to decode and trigger on a LIN serial bus signal. In addition, you will learn how to use the scope’s automatic LIN Search & Navigation capability, as well as Segmented Memory acquisition.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 73 Capturing a LIN frame using the scope’s Edge triggering mode. You should now see on your scope’s display what appears to be an un- triggered display of a digital burst signal similar to Figure 73. Your scope is actually triggering on random rising edges of channel- 1, which is the scope’s default trigger condition.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 74 Decoding a LIN bus while triggering on any rising edge of the input signal. You should now see LIN protocol decoding of this signal on your scope’s display similar to Figure 74, but we still haven’t established stable triggering. The scope is still triggering on any rising edge of channel- 1 (default trigger condition). Let’s now set up the scope to trigger on a LIN frame with the ID = 21HEX.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 75 While triggering on LIN frame = 21HEX, the scope’s hardware-based decoding reveals parity bit errors in the frame ID field. Your scope should now be triggering on LIN frame = 21HEX as shown in Figure 75. With this scope’s very fast hardware- based decoding, you should also see that the frame ID field (left- most decoded byte) is sometimes displayed in red.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs As you scroll through the data, note that waveforms “track”. This means that the frame that the arrow points to in the lister table corresponds to the waveforms that are positioned at center- screen. If you want to zoom in on a particular LIN frame of data, tap the Zoom to Selection softkey. Looking for infrequent errors in this long decoded record can be difficult.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs time of 2 seconds. Note that the number of “found” events is indicated near the bottom of the display. To automatically navigate to each LIN error, press the and front panel navigation keys. Let’s now use the scope’s Segmented Memory mode of acquisition to capture 500 consecutive occurrences of the LIN frame that the scope is currently set up to trigger on (either ID = 21HEX or ID = 12HEX).
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 77 Using the scope’s Segmented Memory acquisition to selectively capture 500 LIN frames of a specific ID. Segmented Memory optimizes oscilloscope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting. In this example, we have selectively captured approximately 15 seconds of total acquisition time as shown in Figure 77.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 78 Lister display shows 500 consecutive occurrences of one particular LIN frame. Because we performed the Segmented Memory acquisition based on triggering on LIN frame ID = 21HEX (or perhaps you changed the trigger condition to trigger on ID = 12HEX), our Lister display now shows a list of consecutive occurrences of just this particular frame ID as shown in Figure 78.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #20: Decoding, Triggering, and Searching on I2S Serial Bus Signals In this lab you will learn how to set up the scope to decode and trigger on the I2S (audio) serial bus traffic. In addition, you will learn how to use the scope’s automatic I2S Search & Navigation capability, as well as Segmented Memory acquisition. This lab does not provide a tutorial on the I2S protocol and signaling.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 79 Capturing I2S signals using the scope’s digital channels of acquisition (MSO). You should now see three digital waveforms captured by the scope’s digital channels of acquisition similar to Figure 79. These I2S training signals are being generated by the scope’s built- in pattern generator and routed directly to the scope’s digital acquisition system; bypassing the logic probe.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 19 Tap the Bus Config softkey; then verify that Word Size is set to “8”, Receiver is set to “8”, Alignment is set to “Standard I2S”, WS Low is set to “Left channel”, SCLK Slope is set “rising edge”. 20 Use your finger to drag the data signals to match the order on the screen's help image by dragging the digital channel identifiers on the far left of the display. Figure 80 Decoding I2S signals.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 24 Press the [Mode/Coupling] key in the Trigger section of the front panel; then select the Normal trigger mode. Figure 81 Triggering on I2S right-channel = +20. Using the default trigger value of arming on right- channel value ≤ - 10 and then trigger on right- channel value ≥ +10, your scope should now be triggering on “R: +20” with this byte shown at center- screen similar to Figure 81.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs the Zoom to Selection softkey. Let’s now perform an automatic search to find every occurrence of Right- channel > +10. We will then automatically navigate to each of these occurrences. 30 Push the horizontal position/delay knob to re- position the trigger point back to center- screen. 31 Set the scope’s timebase to 10.00 ms/div. 32 Press the [Search] front panel key.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 indicated near the bottom of the display. To automatically navigate to right- channel data byte > +10, press the keys. and front panel navigation Let’s now use the scope’s Segmented Memory mode of acquisition to capture 100 consecutive occurrences of I2S serial bus traffic when right- channel > +10. But to complete the rest of this lab your scope must be licensed with the Segmented Memory option.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 83 Using the scope’s Segmented Memory acquisition to selectively capture more I2S traffic. Segmented Memory optimizes oscilloscope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting. In this example, we have selectively captured over 700 ms of total acquisition time as shown in Figure 83.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #21: Decoding, Triggering, and Searching on FlexRay Serial Bus Signals In this lab you will learn how to set up the scope to decode and trigger on FlexRay serial bus traffic. In addition, you will learn how to use the scope's automatic FlexRay Search & Navigation capability, as well as use Segmented Memory acquisition to capture multiple and consecutive occurrences of a particular operation.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 84 Random edge triggering on a FlexRay signal. 8 Press the [Serial] front key. 9 Tap the Mode softkey; then select the FlexRay serial decode mode. 10 Tap the Signals softkey and verity that Source is defined as channel- 1, and that Baud is defined as 10 Mb/s (default conditions). 11 Press the (Back) front panel button (above power switch) to return to the previous menu.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 85 Fast, hardware decoding of FlexRay frames. Note that your scope should still be triggering on random edge crossings of channel- 1. Let's now set up the scope to trigger when it detects a frame with ID=1. 12 Press the [Trigger] front panel key; then select Serial 1 (FlexRay). 13 Tap the Trigger on: softkey; then select Frame. 14 Tap the Frames softkey. 15 Set Frame ID to 1.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs there is not an explicit Cycle count trigger. If you wish to trigger on the same cycle count, set Rep to 64, and use the Bas setting to scroll to a specific cycle count. You should now see stable waveform traces on your scope's display similar to Figure 86. This frame represents Frame ID 1 on all cycles (this signal only uses two cycles).
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lister Menu on the top right of the signal list, and tap the Zoom to Selection softkey. Let's now perform an automatic search to find every occurrence of a particular Frame ID. We will then automatically navigate to each of these occurrences. 20 Push the horizontal position/delay knob to re- position the trigger point back to center- screen. 21 Set the scope's timebase to 100.00 µs/div.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 87 Using the lister in conjuction with the search feature to find specific Frame IDs. Let's now use the scope's Segmented Memory mode of acquisition to selectively capture 500 consecutive occurrences of our trigger condition (Frame ID = 1).
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 32 Tap the Segmented softkey; double- tap on # of Segs and set the value to 500. 33 Tap the Segmented softkey to begin a Segmented Memory acquisition. 34 Tap the Current Segment softkey; then turn the Entry knob to review all 500 captured segments. 35 Set the Current Segment to 500 and note the time- tag of the last captured segment.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #22: Decoding, Triggering, and Searching on Universal Serial Bus (USB) Signals In this lab you will learn how to set up the scope to decode and trigger on USB traffic. In addition, you will learn how to use the scope's automatic Search & Navigation capability, as well as use Segmented Memory acquisition to capture multiple and consecutive occurrences of a particular operation.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 89 Random edge triggering on USB traffic. 12 Press the [Serial] front key. 13 Tap the Mode softkey; then select the USB serial decode mode. 14 Tap the Speed softkey and select Low. 15 Tap the Signals softkey and verity that D+ Source is defined as channel- 1, and that D- Source is defined as channel- 2 (default conditions). Set each Threshold levels to ~1.4 V if not set already.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 90 Fast, hardware decoding of USB traffic. Note that your scope should still be triggering on random edge crossings of channel- 1. Let's now set up the scope to a specific trigger point - when it detects an IN token packet. 17 Press the [Trigger] front panel key; then select Serial 1 (USB). 18 Tap the Trigger on: softkey; then select Token Packet.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 91 Triggering on IN Token packets. 20 On the top right of the waveform display, tap the double down arrows to expand the lister to half screen mode. The lister will display a time organized list of all decoded traffic. 21 Zoom out the scope's timebase to 100 µs/div. As the lister scrolls data, notice the NAK packet that is appearing. Let's trigger on that.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 92 Using the full screen lister to view decoded information. Next, let's explore the Search and Navigate feature of the 4000 X- Series and see how it can help you identify errors. 23 Use the double up arrows to set the lister to half screen. 24 Set the timebase to 1.0 ms/div. 25 Press the [Search] key in the Horizontal control portion of the front panel. 26 Under the Search menu, Select Serial 1: USB.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Next, let's explore how the scope can save and decode hundreds of errors at once using segmented memory. 30 Press [Trigger], and from the Trigger softkey, and select All Errors. 31 Set the timebase to 20.00 µs/div. Press the horizontal control knob to reset the timebase. 32 Press the [Acquire] front panel key. 33 Tap the Segmented softkey; double- tap on # of Segs and set the value to 500.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 93 Using the scope’s Segmented Memory acquisition to selectively capture more USB traffic.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Lab #23: Decoding, Triggering, and Searching on ARINC 429 Signals In this lab you will learn how to set up the scope to decode and trigger on ARINC 429 traffic. In addition, you will learn how to use the scope's automatic Search & Navigation capability, as well as use Segmented Memory acquisition to capture multiple and consecutive occurrences of a particular operation.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 94 Random edge triggering on ARINC-429 traffic. 7 Press [Serial] on the front panel of the scope. 8 In the Mode menu, select ARINC 429. 9 In the Signals menu, set High Threshold to +1.0 V and Low Threshold to -1.0 V. These determine how high or low a signal needs to go to qualify for logic levels. In a true ARINC 429 signal, the signal voltages are set to +10 V, but for this example signal, they are only +2.
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 95 Fast hardware decoding of ARINC-429 traffic. 12 Switch the Trigger from Word Start to Label. Tap the Label softkey and rotate the Entry knob to select a value of 076. You should now see a stable trigger, as a word with label 076 only occurs once in the repetitive training signal built into the machine. Reference Figure 96. Next, let's widen the scope's timebase and look how the search tool works.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 96 Triggering on a frame with label 076. 13 Set the scope timebase to 2.000 ms/div. 14 Press the [Search] feature in the Horizontal area of the front panel. 15 You will notice a display pop up telling you to enable the Lister feature in order to search. Do this by tapping the double down arrows in the top right corner of the waveform display, which brings up a half screen Lister window.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 97 Using the lister to view decoded information. Next, we will explore how you can utilize Segmented Memory to capture large amounts of waveforms with high fidelity. It works by capturing and saving the data you want, and skipping everything between. What you get is high resolution waveforms in high quantity (up to 1000).
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Lab #24: Decoding, Triggering, and Searching on MIL-STD-1553 Signals In this lab you will learn how to set up the scope to decode and trigger on MIL- STD- 1553 traffic. In addition, you will learn how to use the scope's automatic Search & Navigation capability, as well as use Segmented Memory acquisition to capture multiple and consecutive occurrences of a particular operation.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 98 Random edge triggering on MIL-STD-1553 traffic. 7 Press [Serial] on the front panel of the scope. 8 In the Mode menu, select MIL-STD-1553. 9 In the Signals menu, set High Threshold to +1.0 V and Low Threshold to -1.0 V. These determine how high or low a signal needs to go to qualify for logic levels.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 99 Fast hardware decoding of serial traffic while triggering on Framed Data. 10 Press [Trigger] on the front panel, and in the Trigger Type menu, select Serial 1: MIL-STD-1553. 11 There are many different options in the Trigger menu for you to choose from; for this example, select Sync Error.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 100 Triggering on a unique sync error. 12 Set the scope timebase to 200.0 µs/div. 13 Press the [Search] feature in the Horizontal area of the front panel. 14 Tap the Search Edge softkey and change the mode to Serial 1: MIL-STD-1553. 15 Open the Lister by tapping the double down arrows to the upper right of the waveform display. White arrows should appear on the top of the waveform, below the Lister window.
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs Figure 101 Using the lister in conjunction with the search feature to find sync errors. Next, we will explore how you can utilize Segmented Memory to capture large amounts of waveforms with high fidelity. It works by capturing and saving the data you want, and skipping everything between. What you get is high resolution waveforms in high quantity (up to 1000).
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4 Figure 102 Zoomed in on a frame with a sync error.
4 150 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4000 X-Series Oscilloscopes Advanced Training Guide
Agilent 4000 X-Series Oscilloscopes Advanced Training Guide A Oscilloscope Block Diagram and Theory of Operation DSO Block Diagram 152 ADC Block 152 Attenuator Block 153 DC Offset Block 153 Amplifier Block 153 Trigger Comparator and Trigger Logic Blocks 154 Timebase and Acquisition Memory Blocks 154 Display DSP Block 155 s1 151
A Oscilloscope Block Diagram and Theory of Operation DSO Block Diagram Acquistion Memory 8-bit ADC Amplifier Attenuator Input BNC DC Offset Scope Display Display DSP Trigger Coupling Timebase System Trig Comp Trigger Logic DC Trigger Level CPU System Figure 103 DSO block diagram Figure 103 shows the block diagram of one channel of acquisition of a typical digital storage oscilloscope (DSO).
Oscilloscope Block Diagram and Theory of Operation A ADC will be 11111111 (255 decimal). If the analog input level to the ADC is equal to 0.0 V, then the output of the ADC will be 10000000 (128 decimal). To obtain the highest resolution and accurate measurements, the input to the ADC must be scaled within its dynamic range, which is ± V.
A Oscilloscope Block Diagram and Theory of Operation of the ADC. If inputting a very high level input signal, you would typically set the V/div setting to a relatively high setting. Using a high V/div setting, the attenuator stage would first attenuate the input signal (gain < 1) to get it within the dynamic range of the amplifier, and then the amplifier may further attenuate the signal (gain <1) to get it within the dynamic range of the ADC.
A Oscilloscope Block Diagram and Theory of Operation timebase setting of 1 ms/div. Let also assume for simplicity that the scope’s acquisition memory depth is just 1000 points. Using these assumptions, the scope should acquire 500 points before the trigger event followed by acquiring 500 points after the trigger event. At this timebase setting, the scope will acquire 1000 points across a 10 ms time span (1 ms/div x 10 divisions).
A Oscilloscope Block Diagram and Theory of Operation reconstruction filter, but it can also “pipeline” the stored and/or processed data into the scope’s pixel display memory. After the data has been “backed out” of acquisition memory, the DSP block then signals the timebase block that it can begin another acquisition. Note that early generations of DSOs did not include an explicit Display DSP block.
Agilent 4000 X-Series Oscilloscopes Advanced Training Guide B Oscilloscope Bandwidth Tutorial Defining Oscilloscope Bandwidth 157 Required Bandwidth for Analog Applications 158 Required Bandwidth for Digital Applications 159 Digital Clock Measurement Comparisons 162 Oscilloscopes have many different specifications that determine the accuracy that signals can be captured and measured. But the primary specification of an oscilloscope is its bandwidth.
B Oscilloscope Bandwidth Tutorial Figure 104 Oscilloscope Gaussian frequency response The lowest frequency at which the input signal is attenuated by 3 dB is considered the scope’s bandwidth (fBW). Signal attenuation at the - 3 dB frequency translates into approximately - 30% amplitude error.
Oscilloscope Bandwidth Tutorial B digital applications based on clock rates or edge speeds, it still applies to analog applications, such as modulated RF. To understand where this 3- to- 1 multiplying factor comes from, let’s look at an actual frequency response of a 1 GHz bandwidth scope. Figure 105 shows a measured frequency response test (1 MHz to 2 GHz) on an Agilent 1 GHz bandwidth oscilloscope.
B Oscilloscope Bandwidth Tutorial But if you need to make accurate measurements on high- speed edges, this simple formula does not take into account the actual highest- frequency components embedded in fast rising and falling edges. Step 1: Determine fastest actual edge speeds A more accurate method to determine required oscilloscope bandwidth is to ascertain the maximum frequency present in your digital signals, which is not the maximum clock rate.
Oscilloscope Bandwidth Tutorial B Table 1 Multiplying factors to calculate required scope bandwidth based on desired accuracy Required Accuracy Require Bandwidth 20% fBW = 1.0 x fknee 10% fBW = 1.3 x fknee 3% fBW = 1.
B Oscilloscope Bandwidth Tutorial Digital Clock Measurement Comparisons Figure 106 shows the waveform results when measuring a 100 MHz digital clock signal with fast edge speeds using a 100 MHz bandwidth oscilloscope. As you can see, this scope primarily just passes through the 100 MHz fundamental of this clock signal, thus representing our clock signal as an approximate sine wave.
Oscilloscope Bandwidth Tutorial B Figure 107 100 MHz digital clock signal captured on a 500 MHz bandwidth scope When we use a 1 GHz bandwidth scope to capture this 100 MHz digital clock, the result is that we now have a much more accurate picture of this signal, as shown in Figure 108. We can measure faster rise and fall times, we observe less overshoot, and we can even observe subtle reflections that the lower bandwidth scope masked.
B Oscilloscope Bandwidth Tutorial Figure 108 100 MHz digital clock signal captured on a 1 GHz bandwidth scope This tutorial on oscilloscope bandwidth focused on oscilloscopes that exhibit a Gaussian frequency response, which is typical of scopes that have bandwidth specifications of 1 GHz and below. Many higher bandwidth oscilloscopes exhibit a frequency response that has a sharper roll- off characteristic.
Agilent 4000 X-Series Oscilloscopes Advanced Training Guide C Related Agilent Literature Table 2 Related Agilent literature Publication title Publication type Publication number Evaluating Oscilloscope Fundamentals Application note 5989-8064EN Evaluating Oscilloscope Bandwidths for your Application Application note 5989-5733EN Evaluating Oscilloscope Sample Rates vs.
C 166 Related Agilent Literature 4000 X-Series Oscilloscopes Advanced Training Guide
Index Symbols +Width measurement, 48 A Acquire key, 7 Analyze key, 7 ARINC 429 serial bus trigger/decode/search, 139 Auto Scale key, 7 automatic parametric measurements, 12, 14 C CAN serial bus trigger/decode/search, 102 counter measurement, 26 cursors, 12 D default setup, 6 Default Setup key, 7 Display key, 7 DSOXEDK, 5 E Edge then Edge trigger mode, 70 Edge triggering mode, 52 Entry knob, 5 F Fall Time measurement, 16 FFT (Fast Fourier Transform), 24 FlexRay serial bus trigger/decode/search, 125 freq
Index 168 4000 X-Series Oscilloscopes Advanced Training Guide
