High Speed Serial Trigger and Decoder Instruction Manual

Instruction ManualHigh Speed Serial Triggersand Decoders:8b/10b64b/66bNRZ 80-bit Pattern

High Speed Serial Triggers and Decoders Instruction Manual

© 2017 Teledyne LeCroy, Inc. All rights reserved.

Unauthorized duplication of Teledyne LeCroy, Inc. documentation materials other than for internal sales anddistribution purposes is strictly prohibited. However, clients are encouraged to duplicate and distributeTeledyne LeCroy, Inc. documentation for their own internal educational purposes.

Teledyne LeCroy is a trademark of Teledyne LeCroy, Inc., Inc. Other product or brand names are trademarksor requested trademarks of their respective holders. Information in this publication supersedes all earlierversions. Specifications are subject to change without notice.

921394 Rev CFebruary 2017

ContentsAbout the Options 1

8b/10b Option 164b/66b Option 280B Symbol Options 2

Serial Decode 3Bit-level Decoding 3Logical Decoding 3Message Decoding 3User Interaction 3Decoding Workflow 4Decoder Set Up 4Setting Level and Hysteresis 8Failure to Decode 10Serial Decode Dialog 10Reading Waveform Annotations 11Serial Decode Result Table 12Searching Decoded Waveforms 19Decoding in Sequence Mode 20Improving Decoder Performance 21Automating the Decoder 22

Serial Trigger 23Requirements 23Restrictions 23Linking Trigger and Decoder 238b/10b Trigger Setup 2464b/66b Trigger Setup 27NRZ Trigger Setup 32Using the Decoder with the Trigger 34Saving Trigger Data 34

Technical Support 36Live Support 36Resources 36Service Centers 36

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About This ManualTeledyne LeCroy offers a wide array of toolsets for decoding and debugging serial data streams.These toolsets may be purchased as optional software packages, or are provided standard with someoscilloscopes.

This manual explains the basic procedures for using serial data decoder and trigger software options.

It is assumed that:

l You have purchased and activated one of the serial data products described in this manual.

l You have a basic understanding of the serial data standard physical and protocol layerspecifications, and know how these standards are used in controllers.

l You have a basic understanding of how to use an oscilloscope, and specifically the TeledyneLeCroy oscilloscope on which the option is installed. Only features directly related to serialdata triggering and decoding are explained in this manual.

Teledyne LeCroy is constantly expanding coverage of serial data standards and updating software.Some capabilities described in this documentation may only be available with the latest version ofour firmware. You can download the free firmware update from:

teledynelecroy.com/support/softwaredownload

While some of the images in this manual may not exactly match what is on your oscilloscopedisplay—or may show an example taken from another standard—be assured that the functionality isidentical, as much functionality is shared. Product-specific exceptions will be noted in the text.

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http://teledynelecroy.com/support/softwaredownload

About the Options

About the OptionsDecodeTeledyne LeCroy decoders apply software algorithms to extract serial data information from physicallayer waveforms measured on your oscilloscope. The extracted information is displayed over theactual physical layer waveforms, color-coded to provide fast, intuitive understanding of therelationship between message frames and other, time synchronous events.

TriggerTrigger and decode (-TD) options enable you to trigger the oscilloscope acquisition upon findingspecific message frames, data patterns, or errors in serial data streams. Conditional filtering atdifferent levels enables you to target the trigger to a single message or a range of matching data.

The oscilloscope on which these options are loaded must be equipped with the appropriate hardwaretrigger:

l 8b/10b triggering requires the 1.25, 3.125, 6.5 or 14.1 Gbps hardware trigger installed

l 64b/66b triggering requires the 6.5 or 14.1 Gbps hardware trigger installed

l NRZ triggering requires the 80-bit Symbolic option installed

8b/10b OptionTeledyne LeCroy offers an 8b/10b Symbolic Decoder for signals based on the 8b/10b encodingscheme. 8b/10b is not a protocol, but a widely used method to encode 8-bit data words within a 10-bitsymbol, or character. The extra bits are used to ensure the long-term ratio of 1s and 0s transmitted is1:1, and the serial data encoding is DC free.

l Any bit transmission longer than five consecutive 1s or 0s is prohibited, which limits therequirements for the lowest required bandwidth in the serial data transmission channel.

l The difference in number between 1 bit and 0 bit transmissions is never more than two.

While there are theoretically 1024 (2 to the 10th power) different 8b/10b encoded bytes possible, farfewer are allowed based on these aforementioned rules.

In order to maintain the DC-free nature of the signal, a running disparity counter is kept for each byte.This count reflects the bias of 1s or 0s from the transmitted byte, and the 8b/10b encoder makes useof the value of this running disparity counter to determine whether to encode the next byte as asymbol of +1 or -1 disparity so as to keep the overall DC bias of the transmitted signal at zero. Thus,there are two valid bit sequences for any byte, depending on the running disparity used.

Serial data standards that use 8b/10b encoding also define special symbols or control charactersthat indicate start or end-of-frame, skips, link idles, or other protocol-specific non-data information.These are commonly referred to as primitives. Many high-speed serial data standards, such as PCIExpress, SATA, SAS, Fibre Channel, etc. use 8b/10b as the underlying encoding method below theprotocol layer. Each standard defines its own set of primitives. Primitives convey more basicinformation than contained in a full protocol decode, but they can be valuable as well for debugging orquality control purposes.

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64b/66b OptionTeledyne LeCroy offers a 64b/66b Symbolic Decoder for signals based on the 64b/66b encodingscheme. Similar to 8b/10b, 64b/66b is not a protocol, per se, but a widely used method to encode 64-bit data within a 66-bit line code. The overhead of 64b/66b is considerably less than 8b/10b encodingdue to the higher ratio of data bits to coding length.

64b/66b is commonly used in optical signaling protocols, such as 10GFC (10 Gb/s FiberChannel), 10GEthernet Passive Optical Network (10G-EPON), and InfiniBand, and also for varieties of 10GBASE,40GBASE, and 100GBASE Ethernet.

The 66-bit data frame consists of a two-bit synchronization header), which is never scrambled,followed by 64 bits of data/control byte transmission, which is always scrambled.

l A sync header of 01 (time-ordered) indicates the 64 bits are entirely comprised of data.l A sync header of 10 (time-ordered) indicates the 64 bits are comprised of an 8-bit type fieldfollowed by 56 bits of control information and/or data.

l Preambles of 00 and 11 are disallowed and generate errors if present.

The 8-bit type field is defined by the protocol that employs the 64b/66b encoding. The remaining 56 or64 data bits are then scrambled using a self-synchronous scrambler function to ensure a reasonabledistribution of zeros and ones in the data. However, there is no requirement for the distribution ofzeros and ones.

Serial data standards using 64b/66b encoding may also define special signal codes indicatingprotocol-specific commands or functionality.

64b/66b encoding differs from 8b/10b encoding in that 64b/66b coding is designed for clock recoveryand stream realignment, but not DC balance or run length limitation, whereas 8b/10b encodingensures DC balance and run length limitation. Therefore, it is possible for there to be 65 continuouszeros or ones and not violate the encoding scheme, provided the scrambling pattern and data arealigned. More than 65 continuous ones or zeros are not permitted because it violates the clockrecovery requirements.

80B Symbol Options80B Symbol TD options are available to activate 80-bit NRZ pattern triggering on oscilloscopes with 6GB/s and 14.1 GB/s hardware triggers. These options include the 8b/10b and 64b/66b decoders andenable symbol triggering for protocols based on these encoding schemes, such as PCIe, SAS, SATA,USB, FiberChannel, Ethernet, DisplayPort, and more.

Similar options designed for oscilloscopes with 3.125 GB/s hardware triggers activate 80-bit NRZpattern triggering and 8b/10b (only) symbol triggering.

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Serial Decode

Serial DecodeThe algorithms described here at a high level are used by all Teledyne LeCroy serial decoders sold foroscilloscopes. They differ slightly between serial data signals that have a clock embedded in dataand those with separate clock and data signals.

Bit-level DecodingThe first software algorithm examines the embedded clock for each message based on a default oruser- specified vertical threshold level. Once the clock signal is extracted or known, the algorithmexamines the corresponding data signal at the predetermined vertical level to determine whether adata bit is high or low. The default vertical level is set to 50% and is determined from a measurementof peak amplitude of the signals acquired by the oscilloscope. For most decoders, it can also be setto an absolute voltage level, if desired. The algorithm intelligently applies a hysteresis to the risingand falling edge of the serial data signal to minimize the chance of perturbations or ringing on theedge affecting the data bit decoding.

Note: Although the decoding algorithm is based on a clock extraction software algorithmusing a vertical level, the results returned are the same as those from a traditional protocolanalyzer using sampling point-based decode.

Logical DecodingAfter determining individual data bit values, another algorithm performs a decoding of the serial datamessage after separation of the underlying data bits into logical groups specific to the protocol(Header/ID, Address Labels, Data Length Codes, Data, CRC, Parity Bits, Start Bits, Stop Bits,Delimiters, Idle Segments, etc.).

Message DecodingFinally, another algorithm applies a color overlay with annotations to the decoded waveform to markthe transitions in the signal. Decoded message data is displayed in tabular form below the grid.Various compaction schemes are utilized to show the data during a long acquisition (many hundredsor thousands of serial data messages) or a short acquisition (one serial data message acquisition).In the case of the longest acquisition, only the most important information is highlighted, whereas inthe case of the shortest acquisition, all information is displayed with additional highlighting of thecomplete message frame.

User InteractionYour interaction with the software in many ways mirrors the order of the algorithms. You will:

l Assign a protocol/encoding scheme, an input source, and a clock source (if necessary) to oneof the four decoder panels using the Serial Data and Decode Setup dialogs.

l Complete the remaining dialogs required by the protocol/encoding scheme.

l Work with the decoded waveform, result table, and measurements to analyze the decoding.

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Decoding WorkflowWe recommend the following workflow for effective decoding:

1. Connect your data and strobe/clock lines (if used) to the oscilloscope.

2. Set up the decoder using the lowest level decoding mode available (e.g., Bits).

3. Acquire a sufficient burst of relevant data. The data burst should be reasonably well centeredon screen, in both directions, with generous idle segments on both sides.

Note: See Failure to Decode for more information about the required acquisitionsettings. A burst might contain at most 100000 transitions, or 32000 bits/1000 words,whichever occurs first. This is more a safety limit for software engineering reasonsthan a limit based on any protocol. We recommend starting with much smaller bursts.

4. Stop the acquisition, then run the decoder.

5. Use the various decoder tools to verify that transitions are being correctly decoded. Tune thedecoder settings as needed.

6. Once you know you are correctly decoding transitions in one mode, continue making smallacquisitions of five to eight bursts and running the decoder in higher level modes (e.g., Words).The decoder settings you verify on a few bursts will be reused when handling many packets.

7. Run the decoder on acquisitions of the desired length.

When you are satisfied the decoder is working properly, you can disable/enable the decoder asdesired without having to repeat this set up and tuning process, provided the basic signalcharacteristics do not change.

Decoder Set UpUse the Decode Setup dialog and its protocol-related subdialogs to preset decoders for future use.Each decoder can use different protocols and data sources, or have other variations, giving youmaximum flexibility to compare different signals or view the same signal from multiple perspectives.

1. Touch the Front Panel Serial Decode button (if available on your oscilloscope), or chooseAnalysis > Serial Decode from the oscilloscope menu bar. Open the Decode Setup dialog.

2. From the buttons at the left, select the Decode # to set up.

3. Select the data source (Src 1) to be decoded and the Protocol to decode.

4. If required by the protocol, also select the Strobe or Clock source. (These controls will simplynot appear if not relevant.)

5. Define the bit- and protocol-level decoding on the subdialogs next to the Decode Setup dialog.

Tip: After completing setup for one decoder, you can quickly start setup for the other decodersby using the buttons at the left of the Decode Setup dialog to change the Decode # .

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Serial Decode

8b/10b Decoder Settings

Basic Dialog

Under Viewing, choose to view/enter data in Hexadecimal or Symbolic format. Hexadecimalautomatically ignores the non-data bits in the 10-bit symbol/character and returns a Hexadecimalvalue for the 8 (or 64) data bits only. Symbolic provides a protocol-specific view of the 10/66-bitsymbol.

Enter the Bit Rate of the bus to which you are connected as precisely as you know it. The valueshould be correct to within 5%. A mismatched Bit Rate will cause various confusing side effects onthe decoding, so it is best to take time to correctly adjust this fundamental value.

Tip: If you are not sure about the value, apply the Bit Rate measurement parameter to thesource trace to determine the exact Bit Rate of your signal.

Enter the vertical Level used to determine the edge crossings of the signal. This value will be used todetermine the bit-level decoding. For guidelines, see Setting Level and Hysteresis.

Select the Protocol to use when viewing Symbolic decodes. Each protocol has a pre-definedtranslation of the symbol into a character name (primitive) . Refer to the latest version of thestandard for a detailed translation table. To use your own primitive translation file, choose Other, thentouch Browse and select the Primitive File.

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Filter Dialog

Use the Filter dialog to specify those primitives that are to be Decoded, and those to be Filtered outof the results. The list of primitives will vary based on your Protocol selection. Select the item, thenuse the Left and Right Arrow buttons to move it in or out of either list.

Hysteresis Dialog

Enter a Hysteresis Level indicating the amount the signal may rise or fall without affecting bittransition; this helps to compensate for noisy signals.

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Serial Decode

8b/10b Control SymbolsThis table provides the standard 8b/10b Control Symbols.

Input RD = -1 RD = +1

HGF EDCBA abcdei fghj abcdei fghj

K.28.0 000 11100 001111 0100 110000 1011

K.28.1 † 001 11100 001111 1001 110000 0110

K.28.2 010 11100 001111 0101 110000 1010

K.28.3 011 11100 001111 0011 110000 1100

K.28.4 100 11100 001111 0010 110000 1101

K.28.5 † 101 11100 001111 1010 110000 0101

K.28.6 110 11100 001111 0110 110000 1001

K.28.7 ‡ 111 11100 001111 1000 110000 0111

K.23.7 111 10111 111010 1000 000101 0111

K.27.7 111 11011 110110 1000 001001 0111

K.29.7 111 11101 101110 1000 010001 0111

K.30.7 111 11110 011110 1000 100001 0111

From Peter A. Franaszek, Albert X. Widmer, et al. "Byte oriented DC balanced (0,4) 8B/10B partitioned blocktransmission code." US Patent 4486739. December 4, 1984.

†Within the control symbols, K.28.1, K.28.5, and K.28.7 are "comma symbols." Comma symbols are used forsynchronization (finding the alignment of the 8b/10b codes within a bit-stream). If K.28.7 is not used, theunique comma sequences 0011111 or 1100000 cannot be found at any bit position within any combination ofnormal codes.

‡ If K.28.7 is allowed in the actual coding, a more complex definition of the synchronization pattern thansuggested by † needs to be used, as a combination of K.28.7 with several other codes forms a false misalignedcomma symbol overlapping the two codes. A sequence of multiple K.28.7 codes is not allowable in any case,as this would result in undetectable misaligned comma symbols. K.28.7 is the only comma symbol that cannotbe the result of a single bit error in the data stream.

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64b/66b Decoder Settings

Enter the Bit Rate of the bus to which you are connected as precisely as you know it. The valueshould be correct within 5%. A mismatched Bit Rate will cause various confusing side effects on thedecoding, so it is best to take time to correctly adjust this fundamental value.

Tip: If you are not sure about the value, apply the Bit Rate measurement parameter to thesource trace to determine the exact Bit Rate of your signal.

Enter the vertical Level used to determine the edge crossings of the signal. This value will be used todetermine the bit-level decoding. Level is normally set as a percentage of amplitude, and defaults to50%. The set Level appears as a dotted horizontal line across the oscilloscope grid. If your initialdecoding indicates that there are a number of error frames, make sure that the level is set to areasonable value.

Select the Protocol to use when viewing Symbolic decodes. Each protocol has a pre-definedtranslation of the symbol into a character name (primitive) . Refer to the latest version of thestandard for a detailed translation table. To use your own primitive translation file, choose Other, thentouch Browse and select the Primitive File.

Check Has FEC if the data packet has Forward Error Correction.

Primitive Translation FileThe software uses several preformatted primitive translation files for Symbolic decoding. These filescan be found on the oscilloscope in D:\Applications\<protocol>. Review the files to see how to formatyour own primitive translation files if you wish to use a custom file for decoding.

Setting Level and HysteresisThe default Level and Hysteresis values are sufficient for decoding most signals, but in some casesit can be beneficial to change them.

LevelThe Level setting represents the logical level for bit transition, corresponding to the physical Low andHigh distinction. Level is normally set as 50% of waveform amplitude, but can alternatively be set asan absolute voltage (with reference to the waveform 0 level) by changing the Level Type to Absolute.

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Serial Decode

Percent mode is easy to set up because the software immediately determines the optimal threshold,but in some cases it might be beneficial to switch to Absolute mode:

l On poor signals, where Percent mode can fail and lead to bad decodes

l On noisy signals or signals with a varying DC component

l On very long acquisitions, where Percent mode adds computational load

The transition Level appears as a dotted, horizontal line across the oscilloscope grid. If your initialdecoding indicates that there are a number of error frames, make sure that Level is set to areasonable value.

HysteresisThe optional Hysteresis setting imposes a limit above and below the measurement level thatprecludes measurements of noise or other perturbations within this band.

A blue marker around the Level line indicates the area of the hysteresis band. As with Level Type,Hysteresis Type may be either a percentage of amplitude or an absolute number of vertical griddivisions.

Hysteresis set as 40 percent of total waveform amplitude (left) and Hysteresis set as equivalent of 1 grid division (right)around an absolute -200mV Level setting.

Note: Usually, you can set the Level and Hysteresis in the same or different modes. For a fewprotocols, Hysteresis can only be set as a number of mV plus/minus the Level.

Observe the following when setting Hysteresis:

l Hysteresis must be larger than the maximum noise spike you wish to ignore.

l The largest usable hysteresis value must be less than the distance from the level to theclosest extreme value of the waveform.

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Failure to DecodeThree conditions in particular may cause a decoder to fail, in which case a failure message willappear in the first row of the summary result table, instead of in the message bar as usual.

All decoders will test for the condition Too small amplitude. If the signal’s amplitude is too small withrespect to the full ADC range, the message “Decrease V/Div” will appear. The required amplitude toallow decoding is usually one vertical division.

If the decoder incorporates a user-defined bit rate (usually these are protocols that do not utilize adedicated clock/strobe line), the following two conditions are also tested:

l Under sampled. If the sampling rate (SR) is insufficient to resolve the signal adequately basedon the bit rate (BR) setup or clock frequency, the message "Under Sampled" will appear. Theminimum SR:BR ratio required is 4:1. It is suggested that you use a slightly higher SR:BR ratioif possible, and use significantly higher SR:BR ratios if you want to also view perturbations orother anomalies on your serial data analog signal.

l Too short acquisition. If the acquisition window is too short to allow any meaningful decoding,the message “Too Short Acquisition” will appear. The minimum number of bits required variesfrom one protocol to another, but is usually between 5 and 50.

In all the above cases, the decoding is turned off to protect you from incorrect data. Adjust youracquisition settings accordingly, then re-enable the decoder.

Note: It is possible that several conditions are present, but you will only see the first relevantmessage in the table. If you continue to experience failures, try adjusting the other settings.

Serial Decode DialogTo first set up a decoder, go to the Decode Setup dialog. Once decoders have been configured, usethe Serial Decode dialog to quickly turn on/off a decoder or make minor modifications to the settings.

To turn on decoders:

1. On the same row as the Decode #, check On to enable the decoder.

As long as On is checked (and there is a valid acquisition), a result table and decodedwaveform appear. The number of rows of data displayed will depend on the Table #Rowssetting (on the Decode Setup dialog).

2. Optionally, modify the:

l Protocol associated with the decoder.

l Data (Source) to be decoded.

3. Check Link To Trigger On to tie this decoder setup to a serial trigger setup.

To turn off decoders: deselect the On boxes individually, or touch Turn All Off.

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Serial Decode

Reading Waveform AnnotationsWhen a decoder is enabled, an annotated waveform appears on the oscilloscope display, allowing youto quickly see the relationship between the protocol decoding and the physical layer. A coloredoverlay marks significant bit-sequences in the source signal: Header/ID, Address, Labels, Data LengthCodes, Data, CRC, Parity Bits, Start Bits, Stop Bits, Delimiters, Idle segments, etc. Annotations arecustomized to the protocol or encoding scheme.

The amount of information shown on an annotation is affected by the width of the rectangles in theoverlay, which is determined by the magnification (scale) of the trace and the length of theacquisition. Zooming a portion of the decoder trace will reveal the detailed annotations.

These overlays appear on a decoded 8b/10b or 64b/66b waveform:

Annotation Overlay Color

Found primitive Navy blue (behind other fields)

Alignment symbols Purple

Control symbols Green

Data symbols Aqua blue

Initial decoding of 8b/10b waveform. At this resolution, no information appears on the overlay.

Zoomed 8b/10b waveform, showing annotation details.

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Serial Decode Result TableWhen View Decode is checked on the Decode Setup Dialog and a source signal has been decodedusing that protocol, a table summarizing the decoder results appears below the grids. This resulttable provides a view of data as decoded during the most recent acquisition, even when there are toomany bursts for the waveform annotation to be legible.

You can export result table data to a .CSV file. See also Automating the Decoder.

Tip: If any downstream processes such as measurements reference a decoder, the resulttable does not have to be visible in order for the decoder to function. Hiding the table canimprove performance when your aim is to export data rather than view the decoding.

Table RowsEach row of the table represents one index of data found within the acquisition, numberedsequentially. Exactly what this represents depends on the protocol and how you have chosen to"packetize" the data stream when configuring the decoder (frame, message, packet, etc.).

Note: For some decoders, it is even possible to turn off packetization, in whichcase all the decoded data appears on one row of the table.

When multiple decoders are run at once, the index rows are combined in a summary table, orderedaccording to their acquisition time. The Protocol column is colorized to match the input source thatresulted in that index.

You can change the number of rows displayed on the table at one time. The default is five rows.

Swipe the table up/down or use the scrollbar at the far right to navigate the table. See Using theResult Table for more information about how to interact with the table rows to view the decoding.

Table ColumnsWhen a single decoder is enabled, the result table shows the protocol-specific details of thedecoding. This detailed result table may be customized to show only selected columns.

A summary result table combining results from two decoders always shows these columns.

Column Extracted or Computed Data

Index Number of the line in the table

Time Time elapsed from start of acquisition to start of message

Protocol Protocol being decoded

Message Message identifier bits

Data Data payload

CRC Cyclic Redundancy Check sequence bits

Status Any decoder messages; content may vary by protocol

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Serial Decode

Example summary result table, with results from two decoders combined on one table.

When you select the Index number from the summary result table, the detailed results for that indexdrop-in below it.

Example summary result table showing drop-in detailed result table.

8b/10b Result TableThis extracted data appears on the detailed result table. Columns can be hidden by customizing theresult table.


Index(always shown)

Number of the line in the table.

Time(µs) Time elapsed from start of acquisition to Start of Frame.

Data Identifier showing data type and parameter association. Typically shown as octal num-bers.

Length Length of data in bytes/10-bit symbols.

RD Running disparity counter. Always -1 or +1, any other number indicates an error.

Primitive Primitive file used for symbolic decoding.

Data (symbolic) Characters in a symbolic decoding or error message.

Section of typical 8b/10b detailed result table.

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64b/66b Result TableThis extracted data appears on the detailed result table. Columns can be hidden by customizing theresult table.


Index(always shown)

Number of the line in the table

FECIdx Forward Error Correction ID

Time(µs) Time elapsed from start of acquisition to start of frame

BlockType Whether block contains Control, Data, or Error bits

TypeField For control-only block types, the TypeField gives the block type as defined by the64b/66b specification

Primitive Primitive type

Block Payload Un-scrambled binary or hexadecimal contents of data block

Section of typical 64b/66b detailed result table.

Note: The data values shown in the table and on the colored overlay are not scrambled.Therefore, the waveform trace you see on screen, which is scrambled, will not exactly matchthe decoded data you see in the table.

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Serial Decode

Using the Result TableBesides displaying the decoded serial data, the result table helps you to inspect the acquisition.

Zoom & SearchTouching any cell of the table opens a zoom centered around the part of the waveform correspondingto the index. The Zx dialog opens to allow you to rescale the zoom, or to Search the acquisition. Thisis a quick way to navigate to events of interest in the acquisition.

Tip:When in a summary table, touch any data cell other than Index and Protocol to zoom.

The table rows corresponding to the zoomed area are highlighted, as is the zoomed area of thesource waveform. The highlight color reflects the zoom that it relates to (Z1 yellow, Z2 pink, etc.). Asyou adjust the zoom scale, the highlighted area may expand to several rows of the table, or fade toindicate that only a part of that Index is shown in the zoom.

When there are multiple decoders running, each can have its own zoom of the decoding highlightedon the summary table at the same time.

Note: The zoom number is no longer tied to the decoder number. The software tries to matchthe numbers, but if it cannot it uses the next zoom that is not yet turned on.

Example multi-decoder summary table, both zoomed indexes highlighted.

Filter Results

Those columns of data that have a drop-down arrow in the header cell can be filtered:Touch the header cell to open the Decode Table Filter dialog.

Select a filter Operator and enter a Value that satisfies the filter condition.

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Operators Data Types Returns

=, ≠ Numeric or Text Exact matches only

>, ≥, <, ≤ Numeric All data that satisfies the operator

In Range, Out Range Numeric All data within/without range limits

Equals Any (on List),Does Not Equal Any (on List)

Text All data that is/is not an exact match to any full value onthe list. Enter a comma-delimited list of values, no spacesbefore or after the comma, although there may be spaceswithin the strings.

Contains, Does Not Contain Text All data that contains or does not contain the string

Note: Once the Operator is selected, the dialog shows the format that may be entered in Valuefor that column of data. Numeric values must be within .01% tolerance of a result to beconsidered a match. Text values are case-sensitive, including spaces within the string.

Select Enable to turn on the column filter; deselect it to turn off the filter. Use the Disable All buttonto quickly turn off multiple filters. The filter settings remain in place until changed and can be re-enabled on subsequent decodings.

Those columns of data that have been filtered will have a funnel icon (similar to Excel) in the headercell, and the index numbers will be colorized.

Example filtered decoder table.

On summary tables, only the Time, Protocol, and Status columns can be filtered.

If you apply filters to a single decoder table, the annotation is applied to only that portion of thewaveform corresponding to the filtered results, so you can quickly see where those results occurred.Annotations are not affected when a summary table is filtered.

View DetailsWhen viewing a summary table, touch the Index number in the first column to drop-in the detaileddecoding of that record. Touch the Index cell again to hide the details.

If there is more data than can be displayed in a cell, the cell is marked with a white triangle in thelower-right corner. Touch this to open a pop-up showing the full decoding.

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Serial Decode

NavigateIn a single decoder table, touch the Index column header (top, left-most cell of the table) to open theDecode Setup dialog. This is especially helpful for adjusting the decoder during initial tuning.

When in a summary table, the Index column header cell opens the Serial Decode dialog, where youcan enable/disable all the decoders. Touch the Protocol cell to open the Decode Setup dialog for thedecoder that produced that index of data.

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Customizing the Result TablePerformance may be enhanced if you reduce the number of columns in the result table to only thoseyou need to see. It is also especially helpful if you plan to export the data.

1. Press the Front Panel Serial Decode button or choose Analysis > Serial Decode, then open theDecode Setup tab.

2. Touch the Configure Table button.

3. On the View Columns pop-up dialog, mark the columns you want to appear and clear those youwish to remove. Only those columns selected will appear on the oscilloscope display.

Note: If a column is not relevant to the decoder as configured, it will not appear.

To return to the preset display, touch Default.

4. Touch the Close button when finished.

On some decoders, you may also use the View Columns pop-up to set a Bit Rate Tolerancepercentage. When implemented, the tolerance is used to flag out-of-tolerance messages (messagesoutside the user-defined bitrate +- tolerance) by colorizing in red the Bitrate shown in the table.

You may customize the size of the result table by changing the Table # Rows setting on the DecodeSetup dialog. Keep in mind that the deeper the table, the more compressed the waveform display onthe grid, especially if there are also measurements turned on.

Exporting Result Table DataYou can manually export the detailed result table data to a .CSV file:

1. Press the Front Panel Serial Decode button, or choose Analysis > Serial Decode, then open theDecode Setup tab.

2. Optionally, touch Browse and enter a new File Name and output folder.

3. Touch the Export Table button.

Export files are by default created in the D:\Applications\<protocol> folder, although you can chooseany other folder on the oscilloscope or any external drive connected to a host USB port. The data willoverwrite the last export file saved, unless you enter a new filename.

Note: Only rows and columns displayed are exported. When a summary table is exported, acombined file is saved in D:\Applications\Serial Decode. Separate files for each decoder aresaved in D:\Applications\<protocol>.

The Save Table feature will automatically create tabular data files with each acquisition trigger. Thefile names are automatically incremented so that data is not lost. Choose File > Save Table from theoscilloscope menu bar and select Decodex as the source.

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Serial Decode

Searching Decoded WaveformsTouching the Action toolbar Search button button on the Decode Setup dialog creates a 10:1 zoom ofthe center of the decoder source trace and opens the Search subdialog.

Touching the any cell of the result table similarly creates a zoom and opens Search, but of only thatpart of the waveform corresponding to the index (plus any padding).

Tip: In summary table mode, touch any cell other than Index and Protocol to create the zoom.

Basic SearchOn the Search subdialog, select what type of data element to Search for. These basic criteria vary byprotocol, but generally correspond to the columns of data displayed on the detailed decoder resulttable.

Optionally:

l Check Use Value and enter the Value to find in that column. If you do not enter a Value, Searchgoes to the beginning of the next data element of that type found in the acquisition.

l Enter a Left/Right Pad, the percentage of horizontal division around matching data to displayon the zoom.

l Check Show Frame to mark on the overlay the frame in which the event was found.

After entering the Search criteria, use the Prev and Next buttons to navigate to the matching data inthe table, simultaneously shifting the zoom to the portion of the waveform that corresponds to thematch.

The touch screen message bar shows details about the table row and column where the matchingdata was found.

Advanced SearchAdvanced Search allows you to create complex criteria by using Boolean AND/OR logic to combineup-to-three different searches. On the Advanced dialog, choose the Col(umns) to Search 1 - 3 and theValue to find just as you would a basic search, then choose the Operator(s) that represent therelationship between them.

19


Decoding in Sequence ModeDecoders can be applied to Sequence Mode acquisitions. In this case, the index numbers on theresult table are followed by the segment in which the index was found and the number of the samplewithin that segment: index (segment-sample).

Example filtered result table for a sequence mode acquisition.

In the example above, each segment was triggered on the occurrence of ID 0x400, which occurredonly once per segment, so there is only one sample per segment. The Time shown for each index in aSequence acquisition is absolute time from the first segment trigger to the beginning of the samplesegment.

Otherwise, the results are the same as for other types of acquisitions and can be zoomed, filtered,searched, or used to navigate. When a Sequence Mode table is filtered, the waveform annotationappears on only those segments and samples corresponding to the filtered results.

Note:Waveform annotations can only be shown when the Sequence Display Mode isAdjacent. Annotations are not adjusted when a Sequence Mode summary table is filtered, onlythe table data.

Multiple decoders can be run on Sequence Mode acquisitions, but in a summary table, each decoderwill have a first segment, second segment, etc., and there may be any number of samples in each. Asin any summary table, the samples will be interleaved and indexed according to their actualacquisition time. So, you may find (3-2) of one decoder before (1-1) of another. Filter on the Protocolcolumn to see the sequential results for only one decoder.

20

Serial Decode

Improving Decoder PerformanceDigital oscilloscopes repeatedly capture "windows in time". Between captures, the oscilloscope isprocessing the previous acquisition.

The following suggestions can improve decoder performance and enable you to better exploit the longmemories of Teledyne LeCroy oscilloscopes.

Decode Sequence Mode acquisitions. By using Sequence mode, you can take many shorteracquisitions over a longer period of time, so that memory is targeted on events of interest.

Parallel test using multiple oscilloscope channels. Up-to-four decoders can run simultaneously, eachusing different data or clock input sources. This approach is statistically interesting because multi-channel acquisitions occur in parallel. The processing is serialized, but the decoding of each inputonly requires 20% additional time, which can lessen overall time for production validation testing, etc.

Avoid oversampling. Too many samples slow the processing chain.

Optimize for analysis, not display. The oscilloscope has a preference setting (Utilities > PreferenceSetup > Preferences) to control how CPU time is allocated. If you are primarily concerned with quicklyprocessing data for export to other systems (such as Automated Test Equipment) rather than viewingit personally, it can help to switch the Optimize For: setting to Analysis.

Turn off tables, annotations, and waveform traces. As long as downstream processes such asmeasurements or Pass/Fail tests reference a decoder, the decoder can function without actuallydisplaying results. If you do not need to see the results but only need the exported data, you candeselect View Decode, or minimize the number of lines in a table. Closing input traces also helps.

Decrease the number of columns in tables. Only the result table rows and columns shown areexported. It is best to reduce tables to only the essential columns if the data is to be exported, asexport time is proportional to the amount of data exchanged.

21


Automating the DecoderAs with all other oscilloscope settings, decoder features such as result table configuration and exportcan be configured remotely.

Configuring the DecoderThe object path to the decoder Control Variables (CVARs) is:

app.SerialDecode.Decoden

Where n is the decoder number, 1 to 4. All relevant decoder objects will be nested under this. Use theXStreamBrowser utility (installed on the oscilloscope desktop) to view the entire object hierarchy.

The CVAR app.SerialDecode.Decoden.Decode.ColumnState contains a pipe-delimited list of all thetable columns that are selected for display. For example:

app.SerialDecode.Decode1.Decode.ColumnState = "Idx=On|Time=On|Data=On|..."

If you wish to hide or display columns, send the full string with the state changed from "on" to "off", orvice versa, rather than remove any column from the list.

Timebase, Trigger, and input Channel objects are found under app.Acquisition.

Accessing the Result TableThe data in the decoder Result Table can be accessed using the Automation object:

app.SerialDecode.Decoden.Out.Result.CellValue(line index, column index)(item index, depth index)

n:= 1 to 4

line index:= 1 to K

column index:= 1 to L

item index:= {0, 1, 2} where 0=Value, 1=StartTime, 2=StopTime

depth index:= 1 to M

22

Serial Trigger

Serial TriggerTD options provide advanced serial data triggering in addition to decoding. Serial data triggering isimplemented directly within the hardware of the oscilloscope acquisition system. The serial datatrigger scrutinises the data stream in real time to recognise "on-the-fly" the user-defined serial dataconditions. When the desired pattern is recognised, the oscilloscope takes a real-time acquisition ofall input signals as configured in the instrument's acquisition settings. This allows decode andanalysis of the signal being triggered on, as well as concomittant data streams and analog signals.

The serial trigger supports fairly simple conditions, such as "trigger at the begining of any packet,"but the conditions can be made more restrictive depending on the protocol and the available filters,such as "trigger on packets with ID = 0x456". The most complex triggers incorporate a doublecondition on the ID and data, for example "trigger on packets with ID = 0x456 and when data inposition 27 exceeds 1000".

The trigger and decode systems are independant, although they are seamlessly coordinated in theuser interface and the architecture. It is therefore possible to trigger without decoding and decodewithout triggering.

RequirementsSerial trigger options require the appropriate hardware (please consult support), an installed optionkey, and the latest firmware release.

RestrictionsThe serial trigger only operates on one protocol at a time. It is therefore impossible to express acondition such as "trigger on CAN frames with ID = 0x456 followed by LIN packet with Adress 0xEBC."

On WavePro, WaveMaster, and LabMaster oscilloscopes, high-speed serial triggers accept input onlyon CH3 when in DBI mode.

Linking Trigger and DecoderA quick way to set up a serial trigger is to link it to a decoder by checking the Link to Trigger ("On")box on the Serial Decode dialog. Linking trigger and decoder allows you to configure the trigger withthe exact same values that are used for decoding the signal (in particular the bit rate), saving theextra effort needed to re-enter values on the serial trigger set up dialogs.

While the decoder and the trigger have distinct sets of controls, when the link is active, a change tothe bit rate in the decoder will immediately propagate to the trigger and vice-versa.

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8b/10b Trigger SetupTo access the serial trigger dialog:

l Touch theTrigger descriptor boxor chooseTrigger > Trigger Setup from the Menu Bar.

l Touch the Serial Type button, and the 8b/10b Standard button.

Then, working from left to right, make the desired selections from the 8B10B dialog.

Source Setup

Note: The data source channel must be C4, or C3B when in DBI mode. This channel will bepre-selected. If using a LabMaster system with multiple acquisition modules, the modulewith the serial trigger hardware installed in it must be connected as Channels 1 through 4.

Caution: If using a differential probe, make sure the + side of the probe is connected to the +side of the serial data signal. If using a cabled input, make sure the + side of the serial datasignal is connected to C4 or C3B (when in DBI mode). If this is not done, the input signal willbe the inverse of what is expected, and the trigger will not trigger properly. To correct thisproblem, either reverse the probe connections, or check the Invert box next to the SourceChannel indicator.

The bit rate can be computed from the acquisition data in many circumstances, but if the pattern isnot random, the bit rate may be miscalculated as a sub-multiple of the actual bit rate. For bestresults, enter a Bit Rate close to what you expect for the serial data signal, then touch Compute BitRate.

If a serial data signal is detected but the bit rate does not match, an “unlocked” indicator will appearunder the PLL (phase-locked loop) label.

Once the bit rate is properly detected and the PLL locks onto the serial data signal, the “unlocked”indicator will change to “locked.”

24

Serial Trigger

EqualizerThis selection is available only with the 6.5 Gb/s and 14.1 Gb/s triggers.

Very high frequencies, such as those found in serial data signals with speeds >5 Gb/s, may be highlyattenuated as they travel through a serial data channel, backplane or printed circuit board. Whilethere are tools available from Teledyne LeCroy to software equalize the acquisition data (e.g., EyeDoctor II, Virtual Probe), this does not help for triggering, since the hardware trigger FPGA triggers onthe oscilloscope acquisition datastream prior to any post-acquisition software equalization. Therefore, Teledyne LeCroy provides the capability to equalize in the trigger FPGA through the use ofa Low (2 dB), Medium (5 dB), or High (9 dB) equalization “boost.” Touch the HF Boost field, and makeyour selection from the pop-up menu.

Note: Equalization is applied only at the FPGA inputs and is not displayed on Channel 4.

Pattern TypeThe trigger can be set to:

l Symbol OR—any one of a group of symbolsl Symbol String—a single 8b/10b symbol or a string of symbolsl Primitive—a pre-defined protocol or a user-defined primitive sequence of symbolsl Protocol Error

Make your selection under Pattern Type, then complete the settings that appear to the right of thisselection.

To highlight the triggered area and make it easier to verify a valid trigger, check Highlight Pattern.

Symbol OR Trigger

Up-to-six 8b/10b symbols may be added to an OR configuration (as shown above). Detection of anyone of these symbols will result in a successful trigger. Touch Symbol OR, then for each Symbol N,select a:

l Type of KSymbol or DSymboll An allowed Valuel An RD (running disparity) of Positive, Negative, or Either

25


Symbol String Trigger

Up to eight 8b/10b symbols may be configured in a sequential string. Detection of the completesymbol string will result in a successful trigger.

Touch Symbol String and for each Symbol N, select a:

l Type of KSymbol, DSymbol, or None

l An allowed Value

l An RD (running disparity) of Positive, Negative, or Either.

Primitive Trigger

If fewer than eight symbols are required, choose Type None for the first unnecessary Symbol. If Noneis chosen, no further selections are permitted to the right of that symbol.

Instead of defining a symbol string for a particular protocol-defined primitive, you may directly choosethe protocol and primitive. Touch Pattern Type Primitive, then touch Protocol and choose the desiredprotocol from the pop-up menu.

For some protocols, you can select a Primitive Type as well. For example, if you choose USB3protocol, you will see a pop-up menu of primitives as defined in the USB3 standard:

If you choose Protocol Others, then Primitive File is enabled, and you can select a user-definedprimitive file from a specific drive location. The file format is simple, and you can easily create anew file by editing the existing primitive file created for each pre-defined protocol.

Error Trigger

26

Serial Trigger

Error triggering may be performed by choosing Pattern Type Protocol Error and selecting an errorcondition:

l Invalid Symbol Error – Each 8b/10b symbol contains 10 bits; theoretically, there are 1024possible 10-bit patterns. However, only 256 of them are valid. If this selection is checked,then the error trigger will trigger on any of the disallowed 768 10-bit patterns.

l Running Disparity Error – 8b/10b encoding is DC free. To ensure this, the long-term ratio of 1sand 0s must be 50% each. Each symbol may have a maximum +/-2 difference in the number of1s and 0s, and each symbol must end with either a +1 (positive) or -1 (negative). If a symboldoes not meet these requirements, it is a Running Disparity Error, and this selection will causea trigger.

You can choose to trigger on either or both errors by checking the desired boxes.

64b/66b Trigger SetupTo access the serial trigger dialogs:

l Touch the Trigger descriptor box or choose Trigger > Trigger Setup from the Menu Bar.

l Touch the Serial Type button, and the 64b/66b Standard button.

Then, working from left to right, make the desired selections from the 64B66B dialog.

Source Setup


Caution: If using a differential probe, make sure the + side of the probe is connected to the +side of the serial data signal. If using a cabled input, make sure the + side of the serial datasignal is connected to C4/C3B. If this is not done, the input signal will be the inverse of whatis expected, and the trigger will not operateproperly. To correct this problem, either reversethe connections, or check the Invert box next to the Source Channel indicator.


27





Very high frequencies, such as those found in serial data signals with speeds >5 Gb/s, may be highlyattenuated as they travel through a serial data channel, backplane, or printed circuit board. Whilethere are tools available from Teledyne LeCroy (Eye Doctor II, Virtual Probe) to software equalize theacquisition data, this does not help for triggering, since the hardware trigger FPGA triggers on theoscilloscope acquisition datastream prior to any post-acquisition software equalization. Therefore,Teledyne LeCroy provides a capability to equalize in the trigger FPGA through the use of a Low (2 dB),Medium (5 dB), or High (9 dB) equalization “boost.” Touch the HF Boost field, and make yourselection from the pop-up menu.

Note: This equalization is applied only at the inputs of the trigger FPGA and is not displayedon Channel 4.

EncodingChoose to view/enter data in either Binary or Hex(adecimal) format.

28

Serial Trigger

Trigger TypeThe trigger can be set on:

l Block 1 OR 2 match—either Data Value 1 or Data Value 2 occurs

l Block 1 THEN 2—Data Value 1 occurs followed immediately by Data Value 2

l Invalid SYNC—SYNC bits are not 01 or 10

l Invalid TYPE—the Block Type byte is not one of the valid choices

l Block 1 match—Data Value 1 occurs (Data Value 2 is disabled on the UI)

l Block 1 mismatch—any frame that is not Data Value 1 occurs

l Block 2 match—Data Value 2 occurs (Data Value 1 is disabled on the UI)

l Block 2 mismatch—any frame that is not Data Value 2 occurs

Your selection will change the remaining controls that appear on the dialog.

To highlight the triggered area and make it easier to verify a valid trigger, check Highlight Pattern.

Block Type and Data BytesSelect a Block Type of Control, Data or Error. The trigger will only test blocks of this type.

Specify the Data Bytes that are to be tested by the trigger. The number of data bytes that should beentered will depend on the block type. Enter the bytes from most significant to least significant. Forexample, if the three bytes are “AABBCC”, then byte D7=AA, D6=BB and D=CC. After updating this field,Data Value 1 is populated.

Block Type Field and Control CharactersThese controls appear only when using the “Control” Block Type.

Block Type Field uses the descriptions shown in Figure 49-7 of IEEE Std 802.3-2008. Choices are:

C0 C1 C2 C3/C4 C5 C6 C7 (0x1e)

C0 C1 C2 C3/O4 D5 D6 D7 (0x2d)

C0 C1 C2 C3/S4 D5 D6 D7 (0x33)

O0 D1 D2 D3/S4 D5 D6 D7 (0x66)

O0 D1 D2 D3/O4 D5 D6 D7 (0x55)

S0 D1 D2 D3/D4 D5 D6 D7 (0x78)

O0 D1 D2 D3/C4 C5 C6 C7 (0x4b)

T0 C1 C2 C3/C4 C5 C6 C7 (0x87)

D0 T1 C2 C3/C4 C5 C6 C7 (0x99)

D0 D1 T2 C3/C4 C5 C6 C7 (0xaa)

D0 D1 D2 T3/C4 C5 C6 C7 (0xb4)

D0 D1 D2 D3/T4 C5 C6 C7 (0xcc)

D0 D1 D2 D3/D4 T5 C6 C7 (0xd2)

D0 D1 D2 D3/D4 D5 T6 C7 (0xe1)

D0 D1 D2 D3/D4 D5 D6 T7 (0xff)

29


In Control Characters, enter the control bytes used in hex pairs. Control characters are 7 bits long,such that the msb of each hex pair is not used. After updating this field, Data Value 1 is populated.

Note: The Data Bytes and Control Character options that appear on pop-up menus aredisplayed from left to right for ease of reading, but this is opposite to how the values areentered in the Data Bytes and Control Characters fields once you make a selection.

Data ValueData Value 1 shows the 64 bits constructed from Data Bytes and Control Characters, ordered frommost significant to least significant. This ordering matches the ordering of the values entered in theData Bytes and Control Characters fields. To adjust the value, touch the field twice, then use thecontrols on the Virtual Keypad pop-up.

l Previous and Next (arrows) position the cursor over characters that are to change.

l 0, 1, and X insert that character.

l Back clears one character back, like a Backspace key.

l Clear will clear all highlighted characters.

l Set to Default restores the original string generated after making your Block Type and DataByte selections.

l OK enters the keypad value into the Data Value 1 field.

Data Value 2 is populated when you press Copy Data Value 1 to 2. It is required only when the triggerconditions test more than one block of data. To modify it, use the Virtual Keypad pop-up, the same asfor Data Value 1.

Sync sets the value of the two sync bits. These are set automatically to “01” when BlockType is”Control”, and to “10” when BlockType is “Data”.

30

Serial Trigger

Bit Ordering64b/66b data frames consist of a two sync bit preamble, which is never scambled, followed by a 64-bit payload, which is always scrambled.

The decoded values shown on the touchscreen (in tables and dialogs) are user data, not thescrambled data transmitted by the protocol. The trigger chip descrambles the input, compares it tothe desired data, and triggers when the descrambled data matches the desired data. However, thewaveform trace you see on the screen is scrambled data and does not exactly match the decodeduser data.

Teledyne LeCroy has opted to order the 66 bits of the block from left to right (most to leastsignificant, 66..0) in order to allow users to easily match the data value for the block to the valuesentered for the data bytes and control characters. Other documentation describing the 64b66b formatmight show the sync bits, data bytes and control characters with the opposite ordering to that we use,such that “01” is listed as the sync bits for Data rather than Control blocks. This can certainly be asource of confusion. It simply means that the opposite ordering was used by the author: 0..66 ratherthan 66..0.

31


NRZ Trigger SetupAccess the serial trigger dialogs:

l Touch the Trigger descriptor box or choose Trigger > Trigger Setup from the Menu Bar.

l Touch the Serial Type button, and the NRZ Pattern Standard button.

Then, working from left to right, make the desired selections from the NRZ Pattern dialog.

Source Setup


Caution: If using a differential probe, make sure the + side of the probe is connected to the +side of the serial data signal. If using a cabled input, make sure the + side of the serial datasignal is connected to Channel 4. If this is not done, the input signal will be the inverse ofwhat is expected, and the trigger will not trigger properly. To correct this problem, eitherreverse the probe connections, or check the Invert box next to the Source Channel indicator.




32

Serial Trigger


Very high frequencies, such as are found in serial data signals with speeds >5 Gb/s, may be highlyattenuated as they travel through a serial data channel, backplane, or printed circuit board. WhileTeledyne LeCroy offers tools (Eye Doctor II, Virtual Probe) to software equalize the acquisition data,this does not help for triggering, since the hardware trigger FPGA triggers on the oscilloscopeacquisition datastream prior to any post-acquisition software equalization. Therefore, we provide thecapability to equalize in the trigger FPGA through the use of a Low (2 dB), Medium (5 dB), or High (9dB) equalization “boost.” Touch the HF Boost field, and make your selection from the pop-up menu.

Note: This equalization is applied only at the inputs of the trigger FPGA and is not displayed.

EncodingThis selection controls the way trigger patterns are entered and displayed:

Binary— Trigger pattern is entered and displayed as a sequence of 80 single-bit values.

Hex – Trigger pattern is entered and displayed as a sequence of 20 hexadecimal symbols.

Trigger PatternsThe trigger can be programmed with up to two 80-bit patterns, called Data Value 1 and Data Value 2.Touching the corresponding field for either Data Value allows the desired trigger pattern to be enteredon the Virtual Keypad pop-up, in either Binary or Hex format (as selected in the “Encoding” section).“Don’t care” values (represented by an “X”) may be entered at any point in the pattern.

Buttons on the right-hand end of the dialog allow the selected Data Value to be quickly set to all 1’s,all 0’s, all X’s, or inverted from the current pattern.

To enable triggering on a Data Value, touch the corresponding Trigger On box to the left of the DataValue field. If both Data Values are enabled, the oscilloscope will trigger when either Data Value 1 orData Value 2 is detected in the input data stream. The gray text above the Data Value 1 field indicatesthe current logical state of the trigger:

Selecting Highlight Pattern adds a green overlay to the trigger pattern on the NRZ waveform trace:

33


Using the Decoder with the TriggerA key feature of Teledyne LeCroy trigger and decode options is the integration of the decoderfunctionality with the trigger. While you may not be interested in the decoded data per se, using thedecoded waveform can help with understanding and tuning the trigger.

Stop and LookDecoding with repetitive triggers can be very dynamic. Stop the acquisition and use the decoder toolssuch as Search, or oscilloscope tools such as TriggerScan, to inspect the waveform for events ofinterest. Touch and drag the paused trace to show time pre- or post-trigger.

Optimize the GridThe initial decoding may be very compressed and impossible to read. Try the following:

l Increase the height of the trace by decreasing the gain setting (V/Div) of the decoder sourcechannel. This causes the trace to occupy more of the available grid.

l Change your Display settings to turn off unnecessary grids. The Auto Grid featureautomatically closes unused grids. On many oscilloscopes, you can manually move traces toconsolidate grids.

l Close setup dialogs.

Use ZoomThe default trigger point is at zero (center), marked by a small triangle of the same color as the inputchannel at the bottom of the grid. Zoom small areas around the trigger point. The zoom willautomatically expand to fit the width of the screen on a new grid. This will help you to see that yourtrigger is occurring on the bits you specified.

If you drag a trace too far left or right of the trigger point, the message decoding may disappear fromthe grid. You can prevent "losing" the decode by creating a zoom of whatever portion of the decodeinterests you. The zoom trace will not disappear when dragged and will show much more detail.

Saving Trigger DataThe message decoding and the result table are dynamic and will continue to change as long as thereare new trigger events. As there may be many trigger events in long acquisitions or repetitivewaveforms, it can be difficult (if not impossible) to actually read the results on screen unless youstop the acquisition. You can preserve data concurrent with the trigger by using the AutoSave feature.

l AutoSave Waveform creates a .trc file that copies the waveform at each trigger point. Thesefiles can be recalled to the oscilloscope for later viewing. Choose File > Save Waveform and anAuto Save setting of Wrap (overwrite when drive full) or Fill (stop when drive full). The files aresaved in D:\Waveforms.

l AutoSave Table creates a .csv file of the result table data at each trigger point. Choose File >Save Table and an Auto Save setting of Wrap or Fill. The files are saved in D:\Tables.

34

Serial Trigger

Caution: If you have frequent triggers, it is possible you will eventually run out of hard drivespace. Choose Wrap only if you're not concerned about files persisting on the instrument. Ifyou choose Fill, plan to periodically delete or move files out of the directory.

35


Technical SupportLive SupportRegistered users can contact their local Teledyne LeCroy service center at the number listed on ourwebsite.

You can also submit Technical Support requests via the website at:

teledynelecroy.com/support/techhelp

ResourcesTeledyne LeCroy publishes a free Technical Library on its website. Manuals, tutorials, applicationnotes, white papers, and videos are available to help you get the most out of your Teledyne LeCroyproducts. Visit:

teledynelecroy.com/support/techlib

The Datasheet published on the product page contains the detailed product specifications.

Service CentersFor a complete list of offices by country, including our sales & distribution partners, visit:

teledynelecroy.com/support/contact

Teledyne LeCroy700 Chestnut Ridge RoadChestnut Ridge, NY, 10977, USAteledynelecroy.com

Sales and Service:Ph: 800-553-2769 / 845-425-2000FAX: [email protected]

Support:Ph: [email protected]

36

http://teledynelecroy.com/support/techhelp

http://teledynelecroy.com/support/techlib

http://teledynelecroy.com/support/contact

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High Speed Serial Trigger and Decoder Instruction Manual

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