Here you can find Frequently Asked Questions (FAQ) gathered from our customer support. We are constantly updating this page as more requests come into our technical support. If you have a question that is not highlighted here, feel free to submit a request here and our technical support will advise you accordingly.

General Issues

1. Do UCD devices support DP operation without Link Training?

UCD devices support currently Fast Link Training. Unigraf has additional custom solutions that support also operation without link training. Please contact Unigraf for details.

2. Is it possible to capture display interface metadata like InfoFrames and SDP using UCD Console?

Yes. With the Event Log feature of UCD Console users can capture all types of packets without limitation. Users can also freely select which types of data will be captured.

3. Can we test Audio with UCD devices?

Yes. In the collection of tests in Source DUT Testing for both HDMI and DP interfaces, there is an audio test called ‘Validate audio signal frequency and glitch-free audio reproduction’.


Can Unigraf UCD test equipment source High Dynamic Range video?

Using the Playback function in UCD Console (Console2!!!) UCD devices can source any combination of Video, Audio, and related Metadata. This makes it possible to play Dolby Vision content provided by Dolby Laboratories. Examples of HDR and HLG content are provided in the Software Bundle installation package. In addition, the user can perform a semi-automatic HDR 10+ Display device test.

UCD-340 &Type-C Port Testing

1. What UCD-340 can do in short?

UCD-340 can operate as DisplayPort Alt Mode compliant Reference Sink or Reference Source. UCD-340 can be used to test USB-C PD protocol the cable flip, or Video and Audio of a USB-C Sink or Source. With the Electrical Testing function, the quality of signals in USB-C connections can also be tested.

2. What is the recommended maximum USB-C cable length when using UCD-340 or UCD-424?

The maximum cable length defined by the USB-C standard is 1 meter. The quality of the signal strongly depends on the connected devices. Unigraf has evaluated in the laboratory that in good conditions a 1.2-meter cable is safe to use.

3. When testing the USB bypass function with UCD we noticed that the data bypass function is functional even though all four lanes are used for DP Alt Mode. What happened?

USB2 and USB3 have dedicated signals in USB-C connection. When all USB3 SuperSpeed lanes are used by DP Alt Mode, USB data can still utilize USB2 signals. If needed, USB2 and USB3 bypass functions can be individually enabled or disabled on UCD Console Roles and Modes tab.

4. Which USB-C signals can be tested with UCD-340 Electrical Testing feature?

UCD-340 Electrical Testing feature can be used to reveal open or shorted pins and voltage failures in the USB-C connectors. The following signals can be tested: Vbus and GND lines, CC lines, SBU lines, HPD line, DDC and CEC lines. Unigraf Electrical Test Cable is needed for the tests.


1. Can UCD devices operate as repeaters between the input and output ports?

UCD-300 series devices are able to operate at one time only either in a sink role or source role. UCD-400 series devices are able to operate simultaneously in a sink role and a source role. The two roles are however independent, and data cannot be bypassed from sink to source connections.

2. Do UCD devices support Variable Refresh Rate (VRR) function?

All UCD Devices that have HDMI Sink role support VRR.


1. Which HDMI and DP interface signals can be tested with UCD-301 Electrical Testing feature?

UCD-301 Electrical Testing feature can be used to reveal open or shorted pins and voltage failures in HDMI and DP interface signals. The following signals can be tested in HDMI and DP corresponding: HDMI: +5 V power line, TMDS and CLK signal lines, HPD line, DDC, and CEC lines. DP: HPD, Main Link, AUX Channel

2. After connecting a DUT Source device to UCD, I cannot see the video in the preview. How to recover?

When connecting a device to UCD, a good practice is to first verify link status on the Link tab. If links are ok, then verify Stream status on the same tab. When using USB-C DP Alt Mode, please also make sure that DP Alt Mode connection has been established. After the links are OK, the preview can be verified on the Video tab. If links fail, please verify the connections, and issue an HPD pulse on the Link page. In the case of USB-C, a Reconnect command can be issued. If links are still not established, close UCD Console, switch off power from the UCD device, wait 5 seconds. After that re-issue power and launch UCD Console. If links are OK, but stream status fails or is unstable, please verify that the video mode is within the capabilities of the UCD device.


How to configure and run automated CRC tests(Test Automation) on USB-C Smartphone with Unigraf’s UCD 240 Test Tool?

Here demonstrates a step-by-step how you can configure and run automated CRC tests on a USB Type-C smartphone with Unigraf’s USB-C DP Alt Mode Test Automation Tool UCD-240.


Unigraf’s DPR-100 has two operating roles: DP Reference Sink and AUX Controller. What is their difference?

As DisplayPort Reference Sink DPR-100 emulates the full operation of a DisplayPort Sink and can be used e.g. to perform DP HDCP CTS Tests. As AUX Controller DPR-100 is connected only to DP AUX Channel and HPD signal to enable automation of DP PHY compliance tests. Main Lane signals are connected to the PHY Test Equipment (oscilloscope), which also controls DPR-100 in the process of testing.

Test Automation

1. How to use UCD Product Family for Test Automation?

Please refer to this Slideshare for Test Automation of USB-C Devices:


2. Is there any example of Test Automation?

An example: “Unigraf UCD-340 Test Automation Setup – Testing a USB Type-C Laptop (MacBook)”

https://youtu.be/p1F7CTymLRM3. How do you make and run a test script?

When you download the latest SW bundle package from the Unigraf downloads, you can use TSI.exe to run the scripts. You can find the “TSI-X reference manual” from the installed package. Please read chapter 7 for scripting.

You would need to create an empty folder, where you have the following files:

TSI.exe is the scripting engine.

Init.tsi file has the device serial number, Replace S/N in the file with your device S/N. You can ask S/N from the device from the command line by giving the command TSI -l (to list devices connected in your PC USB3 port)

Macros.tsi is the file containing macros. TSI scripting engine allows creating macros by combining multiple commands as one command.

MyTestScript.txt is the test script to run. Execute it from the command line by giving the command TSI -r YourTestScript.txt

MyTestScript.td is the parameter file containing test parameters. You can create this file with UCD Console by the export button to save parameters in the file.

You may learn more about scripting from C:\Program Files (x86)\Unigraf\TSI\SDK\TSI_Automation_Script_Examples\


Does UCD Test Equipment support Linux OS?

UCD Console and TSI API currently support Ubuntu 18.04 LTS and higher. Please contact Unigraf Support for details about support for other Linux families.



Are there any instructions for how to run HDCP 2.2 compliance test on DP sink, source, and repeaters?

A brief description of HDCP 2.2 standard. A straightforward setup for HDCP 2.2 Compliance Test (CTS):

Click here  and Here