About display communication
QAWeb Agent is the software in charge of communicating with Barco clinical or diagnostic displays. To be able to communicate, there needs to be an available communication channel:
- USB: Preferred communication channel. Most reliable and fast.
- DDC: Display Data Channel is a protocol for display communication via the display controller (DVI or DisplayPort)
If your display is not recognized in QAWeb, then you may have issues with one of these communication channels. More about this in the next paragraphs.
What are the consequences if QAWeb cannot communicate with my display?
This display communication is required for running calibration and quality assurance actions to ensure your display is compliant at all times. Also, the asset management functionality on the QAWeb Server relies on this communication to ensure all reporting is correct.
How can I see that my display is not (properly) recognized?
Depending on the situation, there are several ways you can see that your display is not properly recognized:
In QAWeb Agent:
Open QAWeb Agent and from there, open the 'Configuration' window. The displays that are not properly recognized are shown with a question mark as in the screenshot below:
There is, however, a possibility that your display is not recognized properly but it is not shown with a question mark as in the screenshot above. If you look at this screenshot, you can see an 'Add display' button. By clicking that and filling out some information about the display, you can manually add the display to the configuration. Then the icon will look just like if the display is properly recognized. So how can you see then if the display is recognized as a Barco display or not?
As you can see in the screenshot below, the Family of the display in this example is 'Color Dental'. Should your display not be properly recognized and manually added, then this family will either be 'Generic Color' or 'Generic Grayscale'. You will also see a 'Remove display' button on the right-hand side. In this example, the family is one of the Barco families and the 'Remove display' button is not visible. All is ok:
On QAWeb Server:
The easiest to see if a display is not properly recognized on the server side is the absence of the display in the workstation overview. If you expect a display to be there and it is not there, then it is very likely that the display is not properly recognized by the QAWeb Agent:
As described in the QAWeb Agent section of this article, you can add any display to QAWeb Agent, even if there is no communication. The display will then be shown on the QAWeb Server. Like with QAWeb Agent, the way to discover whether it is properly recognized is to look at the family. If the server-side family is 'Generic Color' or 'Generic Grayscale', then your display is not properly recognized.
USB communication
All Barco diagnostic and Clinical displays support USB connection (except for a few very old models which are not supported anymore and therefore will not be listed here). To allow USB communication between the display and QAWeb Agent, simply connect a USB cable between the workstation and the downstream USB port of the display.
Again, this is the recommended setup for any display because of its speed and reliability.
DDC communication
DDC communication happens via the video cable, supported on DVI and DisplayPort in our configurations. One important prerequisite, however, is the availability of a display controller (and driver) that supports DDC communication. All Barco MXRT display controllers (and the drivers we develop for those) support DDC over DVI and DisplayPort.
Third-party display controllers, however, tend to not be so stable in terms of DDC communication. We have seen a lot of communication issues that were caused by third-party display controllers. Therefore we always recommend connecting a USB cable when you are using a third-party display controller such as an NVidia or ATI-branded one.
