Unigraf DisplayPort DPA-400 User manual

DPA-400
DisplayPort™
AUX Channel
Monitor
USER MANUAL

QUICK START Guide
2
Copyright
This manual © 2019 Unigraf Oy. All rights reserved
Reproduction of this manual in whole or in part without written permission of
Unigraf Oy is prohibited.
Notice
The information given in this manual is verified in the correctness on the date of issue. The
authors reserve the rights to make any changes to this product and to revise the information
about the products contained in this manual without an obligation to notify any persons about
such revisions or changes.
Edition
DP AUX Channel Monitor User Manual, Version 10
Document identifier: KH65920
Date: 16 December 2019
Company information
Unigraf Oy
Piispantilankuja 4
FI-02240 ESPOO
Finland
Tel. [phone]
[email protected]
https://www.unigraf.fi/
http://www.unigraf-china.cn
Trademarks
Unigraf and DPA are trademarks of Unigraf Oy.
DisplayPort™ and the DisplayPort™ logo are trademarks owned by the
Video Electronics Standards Association (VESA®) in the United States and other countries.
HDCP is a trademark of Digital Content Protection LLC.
USB™, USB Type-C™ and USB-C™ are trademarks of USB Implementers Forum Inc.
Windows® 10, Windows® 8, Windows® 7 and Windows® XP are trademarks of
Microsoft Corporation.
All other trademarks are properties of their respective owners.

QUICK START Guide
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Table of Contents
QUICK START Guide.......................................................................................................4
1. ABOUT THIS MANUAL....................................................................................5
2. GENERAL........................................................................................................6
Introducing the DPA-400..................................................................................6
Functionality in a Nutshell................................................................................7
DPA-400 Versions................................................................................8
3. SETUP INSTRUCTIONS.................................................................................9
Contents of the Delivery...................................................................................9
Product Setup..................................................................................................9
Installing the DPA-400..........................................................................9
GUI Setup......................................................................................................10
Selecting the COM Port Used.............................................................10
Adding the License Key......................................................................11
Upgrading the License........................................................................11
DPA-400 Firmware Upgrade..........................................................................13
4. DATA ACQUISITION.....................................................................................14
Getting Ready................................................................................................14
The Main Window..........................................................................................15
Controlling the Acquisition..............................................................................16
Starting and Stopping Data Acquisition ..............................................16
Monitored Signals...............................................................................17
Acquiring Data ...............................................................................................18
Decoding the Data.........................................................................................19
Inspecting the Acquired Data.........................................................................20
Lines...................................................................................................20
Columns .............................................................................................20
Message Details.................................................................................22
Filtering...............................................................................................23
Customizing the Main Window.......................................................................25
Selecting Data Columns.....................................................................25
Selecting Font and Colors ..................................................................25
Transaction List Color Options............................................................25
Highlighted DPCD Address Ranges ...................................................26
Searching for Data..............................................................................27
5. SAVING YOUR DATA ...................................................................................28
Saving to a Binary File...................................................................................28
Creating a Test Report...................................................................................28
Test Report Views..........................................................................................29
Appendix A: Specifications .............................................................................................31
General...............................................................................................31
Interfaces............................................................................................31
Appendix B: I/O Connector.............................................................................................32
Appendix C: Advanced Filters.........................................................................................33

QUICK START Guide
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QUICK START GUIDE
If you feel confident with installing new hardware and software in your PC you can attempt
this simplified version of Unigraf DP AUX channel monitor (DPA-400) setup procedure
Serial Communication and License Key Setup
Run the DPA-400 Setup installer
Plug the USB connector of the DPA-400 to one of the USB ports in your PC.
Launch the DPA-400 GUI (DP_AuxMon.exe)
Indicate the DPA-400 unit in the combo-box and click Try Connection.
Insert the 32 character long License Key in the field provided and click Continue.

ABOUT THIS MANUAL
5
1. ABOUT THIS MANUAL
This manual introduces you to the installation and use of the Unigraf DP AUX Channel
Monitor DPA-400. The purpose of this document is to:
•Provide instructions on how to install the provided software.
•Give an overview of the DPA-400 and of its features.
•Guide to the DPA-400 typical usage.
Product Versions
Functionality and operation described in this manual is related to software release 1.7. Please
contact Unigraf for details about other versions or refer to the version specific release notes.
Notes
On certain sections of this manual, when important information is given, text is formatted as
follows. Please read these notes carefully.
Note This text is an important note

GENERAL
6
2. GENERAL
Introducing the DPA-400
The Unigraf DP AUX Channel monitor is a compact, pocket sized device that provides a full
DisplayPort™ AUX channel traffic analysis. DPA-400 and its Windows GUI tool enable the
user to monitor, capture, parse and document all messages sent by DisplayPort™ source, sink
or branch devices.
Each message is shown as time stamped raw data and also in its decoded form, expressed with
the same terminology used by the DisplayPort™ standard specification. Also the activity of the
Hot Plug Detect (HPD) signal and optionally other external signals is tracked and documented
by a time stamp marking each of its changes of state.
Easy to Use
The DPA-400 is a USB-powered device and measures only 10.5 x 13 x 3.5 centimeters,
making it an ideal tool for a laboratory desktop and a snappy companion for a laptop computer.
DPA-400 preserves signal integrity by bypassing the Main Stream data lanes with the provided
special cable. DPA-400 can be inserted between a sink and a source without needing any
custom adapters or expensive pods.
Benefits
•Device independent
•Data documented with time stamps
•Pocket Size
•USB controlled and powered
Applications
•Tool in solving interoperability issues
•Essential partner with Link compliance testing
•Software debug and validation
•Documentation of functionality and protocol implementation
•Monitoring and time measurement of events

GENERAL
7
Functionality in a Nutshell
The DPA-400 is meant to be connected between a DisplayPort™ source and a DisplayPort™
sink device or two USB-C ports with DisplayPort Alternate Mode capability in order to detect
and record the AUX channel communication between them. The DPA-400 does not take part
to the communication but transparently monitors the AUX channel traffic, the HPD (Hot Plug
Detect) line and three external digital inputs.
The user can select to start the acquisition manually or on a specific transition (rising edge or
falling edge) of one or more of the external inputs or of HPD. The user can also terminate the
acquisition manually or on a different transition of the same input signals.
When the acquisition is enabled, each AUX channel transaction detected is stored in the DPA-
400 internal memory and marked by a timestamp, starting from the time instant the acquisition
begun.
The user can also select one or more of the external input signals or the HPD for being
monitored. Every logical state change of the monitored signals is recorded together with the
timestamp of when it happened. This is very useful, for instance, to know when HPD gets
asserted and how long time each HPD pulse issued has taken.
The GUI application is used to control the acquisition start and stop, to select the monitored
signals and to browse through the acquired data in a user-friendly fashion. The DPA-400
features a large internal memory that can quickly collect a huge amount of data. The user can
download the data stored in the DPA-400 memory to the GUI as soon as it gets acquired or can
pause the download to first inspect the already visible data. The download can be paused and
restarted any number of times or aborted if the acquired data is not of interest.
After the acquisition is stopped, the downloaded data can be saved in binary format or as a
portable HTML report. In its binary form, the saved data can only be opened by the DPA-400
GUI while in HTML format it can be opened with any available HTML browser.

GENERAL
8
DPA-400 Versions
There are multiple versions of DPA-400. All versions share the same test equipment hardware,
but more recent versions of the DPA-400 GUI support later versions of DisplayPort DPCD
register structure and other more advanced features. Please see the table below.
Version
Added features
DPA-400
DPCD 1.X, HDCP 1.X decoding
DPA-400 1.2
DPCD 1.2 decoding, Sideband CH messages
DPA-400 1.4
DPCD 1.4, HDCP 2.2 decoding
DPA-400 2.0
DP 2.0 support for DPCD 1.4 decoding, including DSC, FEC and
LTTPR specific DPCD registers
DPA product delivery contains a custom Y-shaped cables for use with DP 1.2 and later
versions. The custom cables bypass the main links outside DPA-400 as shown in the
illustration on the previous page.
Note Please use the custom cable supplied with DPA-400 when monitoring DisplayPort version 1.2
and higher. DPA-400 hardware is not compatible with the HBR2 and higher main link bit rate.
The custom cable bypasses main links outside DPA-400.
Note Please make sure that you have connected the DP cables right:
DP Source >> DP Input, DP Output >> DP Sink Device
Connect to
DP Source /
DFP_D
Connect to
DP Sink /
UFP_D
N.B. Cables with DP Connector and USB-C Connector are separate

SETUP INSTRUCTIONS
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3. SETUP INSTRUCTIONS
Contents of the Delivery
The DPA-400 installation SW package includes the following items:
•DPA-400 Setup installer (DPA-400 Setup.exe)
•Firmware updater utility (UUFUpd.exe)
•Latest DPA-400 firmware (*.uuf)
•Release notes (DPA-400_release_notes.txt)
•This manual
DPA-400 delivery also includes custom cables for monitoring DisplayPort versions 1.2 and
above and DisplayPort Alt mode over USB-C interface.
•DP to DP Y-cable 2 meters (P/N 546098)
•DP to DP Y-cable 0.5 meters (for high link rates) (P/N 546118)
•USB-C to USB-C Y-cable 1 meter (P/N 546109) (ordered separately).
Product Setup
The DPA-400 unit features an USB to serial conversion controller. Therefore its Windows
driver will be installed as a virtual serial port named as a DPA-400 USB Serial Port. Please,
use the USB Serial Port driver installed by DPA-400 installer.
Note: System administrator's privileges are required for performing the installation.
Installing the DPA-400
In order to install the DPA-400 software and driver please follow these steps:
Power up your PC
Open the folder containing DPA-400 installation package
Run DPA-400 Setup.exe found in the installation package
In the Choose Components dialog please indicate if you need the device drivers to be installed
at this time.
In the following dialogs, indicate the folder where the files will be installed and the Start Menu
folder for the program shortcuts.
DPA-400 software and firmware will now be installed to your PC.
Plug in the DPA-400 unit in a vacant USB port of your PC
Run DP-Aux Channel Monitor application

SETUP INSTRUCTIONS
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GUI Setup
In order to enable the DPA-400 graphical user interface (GUI) application to communicate
with the firmware in the DPA-400 unit, you have to set up the COM port used and provide the
license code delivered with the unit.
Selecting the COM Port Used
From the GUI pull down menu in the center of the GUI and select the serial port used for
communicating with the DPA-400. It will in most cases be named as DPA-400 USB Serial Port

SETUP INSTRUCTIONS
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Adding the License Key
You will need a hardware specific license key for using Unigraf DPA-400 GUI. Each license is
valid for one specific device only. By using the GUI you can read the Seed Number of your
DPA-400 unit. For a given Seed Number, Unigraf will provide you a License Key that will
enable you to use the GUI from any PC to control your DPA-400 GUI, the user can select the
interpreted DPCD registers based on the DP version.
You can usually find your DPA-400 License Key on a sticker glued on its enclosure, in the
delivery package or among its related documents. If you cannot locate the License Key, please
email to Unigraf the Seed Number shown on the dialog in order to receive your License Key.
Insert each of the 32 character long License Key in the field provided and click the Continue.
The license key is now saved in your PC and you can constantly use the device from this PC.
Please Click Close to return to the main window.
Upgrading the License
For upgrading your license please select Decoding > Enter new license. In the license entry
dialog, please type in or copy and paste the new license and click Continue.

SETUP INSTRUCTIONS
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Note Please note that each Unigraf DPA-400 GUI license is bound to one specific DPA-400 unit.
The same license can be used with any number of PCs.
Note Please note that various features of DPA-400 are enabled with license keys. For upgrading
your DPA-400, please contact Unigraf.
Note The License Key never includes characters I, G, B, O because of their similarity with the
corresponding numbers. If in doubt, please use numbers. You can use copy and paste to insert
the License Key.
Note The DPA-400 must be connected to your PC for entering the License Key.

SETUP INSTRUCTIONS
13
DPA-400 Firmware Upgrade
When launching the GUI, it will verify that the firmware programmed in the DPA-400 unit is
matching the GUI version. If upgrade is needed the GUI will prompt the user to update the
firmware.
Please follow these steps in order to upgrade your DPA-400 internal firmware:
Unplug the DPA-400 USB cable.
With a length of wire, short-circuit pins 1 and 6 of the digital I/O connector. Try to make a
good contact by inserting at least ½” of bare conductor in each of the connector pin holes.
Plug the DPA-400 USB cable to your PC.
Locate the COM port used by your DPA-400 (for instance, COM3).
Open Windows command prompt dialog and go to the directory where the installer copied the
firmware files. (by default c:\Program Files (x86)\Unigraf\DPA-400\ Firmware). In this
directory you should find the updater, UUFUpd.exe, and the FW file, e.g. dpa-400.uuf.
In Windows command prompt run:
uufupd -c 3 -f dpa-400.uuf
(In the entry, please substitute “3” with the number of your COM
port and “dpa-400.uuf” with the firmware file included in your
package)
The UUFUpd utility will upgrade the DPA-400 firmware while printing a series of dots. Please
wait for its completion without removing the USB cable.
When the message “DONE” is printed, please remove the short-circuit from the I/O connector
and unplug the USB cable. Your DPA-400 is now upgraded with its latest firmware.
In case you receive an error message from the UUFUpd utility, please restart the above
procedure from its very beginning (USB cable unplugged) and verify that the short-circuit you
use makes a good contact and to the right pins.
Note After a firmware upgrade, the DPA-400 USB cable must be unplugged and plugged once for
the device to be again functional.

DATA ACQUISITION
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4. DATA ACQUISITION
Unigraf DP AUX Channel Monitor consists of DPA-400 unit for connecting to the
DisplayPort™link and a Graphical User Interface (GUI) application for operating it and
creating reports. The serial communication setup and License Key entry are covered in the
Setup Instructions section of this manual. The following sections describe the process of
acquiring AUX channel data. Generating data reports is covered in its own chapter.
Getting Ready
Plug your DPA-400 to your PC and start the GUI application. Verify that the right COM port is
selected, a valid License Key is available and the GUI main window opens.
If required, connect your external input signals to the DPA-400 I/O connector using a suitable
cable.
Note In order to ensure the signal integrity of high main data lane speeds (HBR2 and higher) you
will need to use the custom Y-shaped pass-by cable supplied with the delivery of DPA-400 or
the Upgrade package. DPA-400 hardware is not compatible with HBR2 and higher data
transfer speed.
Note Please make sure that you have connected the DP cables right:
DP Source >> DP Input, DP Output >> DP Sink Device

DATA ACQUISITION
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The Main Window
The GUI main window is divided into two sections. The Transaction list in the left displays
the acquired AUX channel transactions and events. The Message details panel on the right
side of the window shows the interpretation of the currently selected AUX channel transaction
line. The Start acquisition button controls the start and stop of the data acquisition. The
Status line at the bottom of the window shows the current GUI state, the amount of data
already downloaded to it and the amount of data still stored in the DPA-400 internal memory
(buffered) and waiting for downloading.
Note Please note that the Filters function found in the Main Window in some previous versions of
the GUI can now be found as a pull down menu. Its function is described later in this
document.

DATA ACQUISITION
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Controlling the Acquisition
The start and stop conditions of the data acquisition and monitoring of optional signals can be
defined in the corresponding dialogs. Please consult Appendix B to find out how these external
signals can be connected to your DPA-400.
Starting and Stopping Data Acquisition
By default, the data acquisition is started immediately after the Start acquisition pushbutton in
the Main window is pressed.Additional conditions can be set in the Start triggers dialog.
Select Tools -> Start triggers…
By default the Start acquisition immediately option is selected. By deselecting it you can
select one or the more of the advanced options:
•Start on the rising or falling edge of HPD signal
•Start on the rising or falling edge of IN0 signal
•Start on the rising or falling edge of IN1 signal
•Start on the rising or falling edge of IN2 signal
The acquisition will start after the Start acquisition pushbutton is pressed and when any of the
selected conditions is verified.
Data acquisition can be manually stopped at any time by pressing the Stop acquisition
pushbutton in the Main window. Optionally, the acquisition can be stopped automatically when
one of the enabled stop conditions is verified.
Select Tools -> Stop triggers…
You can select one or the more of the advanced options:
•Stop on the rising or falling edge of HPD signal
•Stop on the rising or falling edge of IN0 signal
•Stop on the rising or falling edge of IN1 signal
•Stop on the rising or falling edge of IN2 signal

DATA ACQUISITION
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The acquisition will stop automatically when any of the selected conditions is verified.
Monitored Signals
In addition to the AUX channel traffic, you can also monitor the status of four digital signals.
By default, only the HPD signal is monitored. In the Monitored signals dialog you can include
also one or more of the external digital signals IN0, IN1 and IN2.
Select Tools > Monitored signals…
The dialog allows you to select the monitored signals.

DATA ACQUISITION
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Acquiring Data
Plug your source and sink devices to the DPA-400 as described in section Getting Ready of this
chapter.
Select the signals to be monitored or check that the HPD is selected.
Check the start and stop triggers.
Finally press the Start Acquisition button.
The GUI enables automatically data download and data is displayed in the Transaction List as
soon as it is acquired and reaches the GUI. From the Status line at the bottom of the Main
window you can monitor the amount of downloaded data and how much data is still waiting to
be downloaded.
Usually the buffered data amount always read as zero, meaning that all of the acquired data has
been downloaded to the GUI. When a quick and long sequence of transactions is acquired or
when a rapidly toggling external input is monitored, the DPA-400 internal buffer can fill-up
much more rapidly than what the GUI is capable of downloading.
If the DPA-400 buffer gets filled with a large amount of data, you can pause the download by
pressing the Pause Download pushbutton.
After inspecting the downloaded data, you can decide to resume the download to gather more
data by pressing the Download pushbutton.
If the acquisition is not stopped automatically by one of the selected stop triggers, you can
force its termination by pressing the Stop Acquisition pushbutton.
Note Restarting the data acquisition clears the DPA-400 internal buffer and the GUI downloaded
data!

DATA ACQUISITION
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Decoding the Data
There are multiple versions of DPA-400. All versions share the same test equipment hardware,
but more recent versions of the DPA-400 GUI support later versions of DisplayPort DPCD
register structure and other more advanced features. Please see the table below.
Version
Added features
DPA-400
DPCD 1.X, HDCP 1.X decoding
DPA-400 1.2
DPCD 1.2 decoding, Sideband CH messages
DPA-400 1.4
DPCD 1.4, HDCP 2.2 decoding
DPA-400 2.0
DP 2.0 support for DPCD 1.4 decoding, including DSC, FEC and
LTTPR specific DPCD registers
From the pull-down menu select Decoding and select the version.
You can select
•DPCD 1.1 Decoder
•DPCD 1.2 Decoder
•DPCD 1.3 Decoder
•DPCD 1.4 Decoder for DP 1.4a
•DPCD 1.4 Decoder for DP 2.0
•Define if DETAILED_CAP_INFO_AVAILBLE bit (DPCD 0x00005) is set to indicate that
DFP capability field is 4 bytes/port for the detailed capability description
•Define if MAIN_LINK_CHANNEL_CODING_SET (DPCD 0x00108) is set to 2 to indicate
128b/132b Link Layer
Note Please note that various features of DPA-400 are enabled with license keys. For upgrading
your DPA-400, please contact Unigraf.

DATA ACQUISITION
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Inspecting the Acquired Data
The data acquired by the DPA-400 and downloaded to the GUI is shown in the Transaction
list. Please refer to chapter Customizing the Main Window below for details on how to modify
the content and look of the Transaction list.
Lines
The data is organized in lines, each numbered starting from 1 and marked with a timestamp.
There are four kinds of lines:
1. Information lines
Identified by the text “INFO” in their Type column, they provide some useful information like
the time acquisition has started and stopped or the logical state of the inputs, etc.
2. Transaction lines
Identified by the text “Native” or “I2C” in their Type column, they report an AUX channel
data transfer, either a data Request or a data Reply.
3. Event lines
Identified by the text “Event” in their Type column, they signal the state change in one or more
of the monitored inputs.
4. Sideband Channel Messages
The Isochronous Transport Service uses the sideband communications over sideband channel
(AUX CH and HPD) for the management of topology/virtual channel connection/Main Link
and performs Main Link symbol mapping.
5. Error lines
A line Type reading “Error” marks the detection of an illegal AUX channel data packet. An
irregular start condition, an irregular stop condition or transfer of a number of bits which is not
a multiple of 8 are all conditions that cause an error line.
6. Trace lines
Combines the data from several lines of a HDCP related message to one entry in Message
details panel for easier readability.
Columns
The data on each line is ordered in columns. Each column provides additional information
about the data line, facilitating its viewing and interpretation:
Line
This column displays the line number, starting from 1, and cannot be hidden.
Timestamp
Each line is identified by its timestamp, marking the instant when an event or error was
detected, or when a data transaction got started. The timestamp can be displayed as a time
delay from the start of the acquisition (absolute) or from the previous line (relative). The
timestamp can be displayed in milliseconds or in minutes, seconds and microseconds.