Almost all boards that have HDMI and/or DisplayPort are unidirectional, or they have two dedicated ports for the purpose of video input and output. I wanted to create a board that had both ports being bi-directional and could be switched whenever needed. I could have made a four-dongle board, two HDMI and DisplayPort, one input and one output. That seems overcomplicated and not needed. My two-dongle solution allows you to have less cables and can still be used for a multitude of reasons. If one has a HDMI only monitor, or has only a working DisplayPort, the board is able to intake either signal and then output the other. The FPGA, SoC, can act as a GPU, or be a signal converter. For example, a camera could input an HDMI signal to the board, the controller could do image processing and then display it via the DisplayPort.

This board should have been made earlier by other computer creators. Regardless of if the technology is a source or sink, the main controller should be able to have bi-directional ports to allow feedback. Both protocols are behind a pay wall for the newest versions, but the older ones are free to all. My board connects to the SYZYGY connector on any compatible board:

The DisplayPort protocol (in a nutshell) sends video data via four differential lanes. There are other ports and those are used for control. The HDMI protocol uses LVDS and TMDS to send video and audio over three differential lanes and one differential clock lane. I have no HDL for this board. This board is based off of TI bidirectional chips. For HDMI:

For DisplayPort, I copied and changed the TIDA board they created:

I removed the USB-C, controller IC and changed the voltage along with a different layout.

I wish I could have this board created, but I am not sure if I could create the HDL that is needed to connect it to my SoC.