HLK Display Capture Test Failure: No Board Detected. What Does It Mean?

Hey guys, running into some HLK test failures can be a real headache, especially when you're dealing with cryptic error messages. Let's break down this “No board detected” error in the context of HLK Display Capture Tests, specifically focusing on Embedded DisplayID 2.0 and Large EDID failures. We'll try to get you pointed in the right direction so you can squash this bug and get your virtual display driver up to snuff.

Understanding the HLK Display Capture Tests

First off, let's set the stage. The Windows Hardware Lab Kit (HLK) is Microsoft's testing framework for hardware and drivers. Passing HLK tests is often a requirement for hardware certification and ensures compatibility with Windows. The Display Capture Tests, in particular, are designed to verify that your display driver correctly implements various display-related technologies, including EDID (Extended Display Identification Data) and display capture functionalities.

When you see failures related to Embedded DisplayID 2.0 and Large EDID, it generally means the system is having trouble reading or interpreting the display identification information provided by your virtual display driver. EDID is crucial because it's how a display device tells the graphics adapter what resolutions, refresh rates, and other capabilities it supports. A “Large EDID” simply refers to an EDID data block that exceeds the standard size. Embedded DisplayID 2.0 is a more recent version of the standard, offering enhanced capabilities.

Now, let’s dive into that perplexing “No board detected!” message. This is where things get interesting, and we need to think about how the HLK tests are structured.

Decoding the "No board detected!" Error

The error message No board detected! accompanied by No display output to display capture device mapping from the configuration file - attempting to auto-map. and Unable to determine any display output to display capture device mappings - tests cannot continue. gives us some strong clues. The key here is the mention of a “board” and the attempt to map display outputs to a display capture device. In this context, "board" typically refers to a video capture card or device – think something like an Elgato Cam Link, a Magewell capture card, or a similar device that can capture video output from a display.

The HLK Display Capture Tests often rely on a physical capture device to record the output generated by your virtual display driver. The test framework needs to know which display output (from your virtual driver) is connected to which capture device. This mapping is usually specified in a configuration file. If the framework can't find a configured mapping, it attempts to auto-map, and if that fails too, the tests can't proceed. The error message clearly indicates that this mapping process is failing because it can't detect the necessary capture "board."

So, to directly answer the question, yes, the test framework likely requires a physical video capture device to run these specific tests (Display Capture Tests - Embedded DisplayID 2.0 and Large EDID). The tests are designed to verify the capture capabilities, which inherently implies the presence of a device to do the capturing.

Why is a Capture Device Needed?

You might be wondering, “Why do I need a physical capture device for a virtual display driver?” That’s a valid question! The reason boils down to the nature of display capture testing. The HLK tests need to verify that your driver can:

• Properly output video signals.
• Correctly provide EDID information.
• Function seamlessly with capture devices that a user might employ.

To validate these aspects, the test setup often involves:

1. Your virtual display driver generating a video signal.
2. This signal being “sent” to a virtual display (simulated).
3. A physical capture device capturing the output of this virtual display.
4. The HLK tests analyzing the captured video and EDID information.

This end-to-end testing approach ensures that your virtual display driver behaves as expected in real-world scenarios where users might connect it to actual capture devices for recording or streaming.

Troubleshooting the "No board detected" Error

Now that we understand the root cause, let’s look at how to tackle this error. Here’s a step-by-step approach:

1. Confirm the Requirement: Double-check the HLK test documentation for the specific Display Capture Tests you're running. It should explicitly state whether a physical capture device is required. Sometimes, certain tests might have alternative execution paths or configurations that don't need a capture device, but this is less common for tests involving EDID and capture functionalities.

2. Physical Device Check: Make sure you have a compatible video capture device connected to your test machine. This could be an internal capture card or an external USB capture device. Ensure the device is properly installed and recognized by Windows. Check Device Manager to confirm there are no driver issues.

3. Configuration File: The HLK tests usually rely on a configuration file that specifies the mapping between display outputs and capture devices. This file might be a .ini or .xml file. Locate this file (its location should be documented within the HLK test instructions) and verify that it correctly identifies your capture device and the corresponding display output from your virtual driver. Common settings include device names, display adapter indices, and connector types.

4. Auto-Mapping Issues: The error message indicates that auto-mapping failed. This could be due to several reasons:

   • The capture device driver might not be correctly reporting its capabilities.
   • The HLK test framework might not be able to enumerate the device properly.
   • There might be conflicts with other display devices or drivers on the system.

   If auto-mapping is failing, manually configuring the device mapping in the configuration file is often the best solution.

5. TanagerPlugin Failure: The original post mentions that the TanagerPlugin failed to load. This plugin is likely responsible for interacting with the capture device. If it can't find a “board,” it suggests a problem with device detection or driver initialization. Focus on the capture device's drivers and ensure they are up to date and compatible with your version of Windows.

6. HLK Test Controller Logs: Examine the HLK Test Controller logs for more detailed error messages. These logs can provide valuable clues about why the TanagerPlugin is failing to load or why the device mapping is not working. Look for specific error codes or exceptions.

7. Virtual Display Driver Configuration: Ensure that your virtual display driver is correctly exposing the necessary display outputs and EDID information. Use tools like MonitorInfoView (a free utility) to inspect the EDID data being reported by your driver. Make sure the EDID is valid and contains the expected information.

8. Test Environment Isolation: Sometimes, conflicts with other software or drivers can interfere with HLK tests. Try running the tests in a clean environment, such as a dedicated test machine or a virtual machine, to minimize potential conflicts.

Example Configuration (Illustrative)

While the exact format of the configuration file will vary depending on the specific HLK test, here's a simplified example to illustrate the kind of information it might contain:

[DisplayCapture]
CaptureDeviceName = MyCaptureDevice
DisplayAdapterIndex = 0
ConnectorType = HDMI

[DisplayOutput]
VirtualDisplayIndex = 1

[Mapping]
DisplayOutput = VirtualDisplayIndex
CaptureDevice = CaptureDeviceName

In this example:

• CaptureDeviceName would be the name of your capture device as recognized by Windows.
• DisplayAdapterIndex is the index of the display adapter hosting your virtual display.
• ConnectorType specifies the connection type (e.g., HDMI, DisplayPort).
• VirtualDisplayIndex identifies the output of your virtual display driver.
• The [Mapping] section links the display output to the capture device.

Remember, this is a simplified example. The actual configuration file format and settings will be specific to the HLK test you are running. Consult the HLK test documentation for precise instructions.

A Quick Recap and Next Steps

To sum it up, the “No board detected!” error in the HLK Display Capture Tests usually indicates that the test framework can't find or communicate with a physical video capture device. This is often necessary for tests that validate display capture functionalities and EDID handling. Troubleshooting involves verifying the presence and configuration of the capture device, checking the HLK test configuration file, and examining driver and plugin behavior.

If you're still stuck, I'd recommend:

• Reviewing the HLK documentation for the specific tests you're failing. It should provide detailed guidance on the test setup and requirements.
• Searching the Microsoft Developer Network (MSDN) forums and other online resources for similar issues. Other developers may have encountered and resolved the same problem.
• Contacting Microsoft support if you have a support agreement. They can provide expert assistance with HLK testing.

I hope this helps you get to the bottom of this! Remember, HLK testing can be tricky, but with a systematic approach, you can overcome these hurdles and ensure your virtual display driver is rock-solid.

For more information on HLK testing and display driver development, check out the official Microsoft documentation on Microsoft Hardware Dev Center. You'll find a wealth of resources to guide you through the process.