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Mini DP to HDMI converter CD0095

Former Member
Former Member

Hi everyone,

I've been working on a MPSoC design with a XU5Ev plateform. I've managed to get a video output from display port controller using petalinux and modetest.

Like many, I'd like to get an HDMI output, which is why I thought about using DP to HDMI adapter. I found this discussion on the forum : /products/devtools/avnetboardscommunity/avnetboard-forums/f/ultra96-hardware-design/38397/ultra96-v2-mini-dp-to-hdmi-adapter

In which the CD0095 seems to the solution. So I got the cable and tried it out !

Unfortunatly, no pattern on screen.

But, I did get the EDID from the screen : 

image

which is quite encouraging.

I did see this two warnings when I disconnected/reconnected the adapter 

image

I'm starting to think that it could be a bug from Xilinx SDK (that wouldn't be a first)

Do you guys use modetest and Petalinux for your tests ? Or do you have another method ? 

I'm starting to think about getting a Ultra96 kit

Regards

  • How many channels have you allocated to DisplayPort in your design? Did you see this comment? "Be aware that the active mini-DP to HDMI CableCreation cable does not support 5.4 Gbps per channel mode and that the ultra96 has only 2 channels for miniDP out."

    I'm not sure about modetest, but I know that our out-of-box design for Ultra96-V2 is PetaLinux-based. Perhaps can provide more detail.

    Bryan

  • Former Member
    Former Member in reply to bhfletcher

    Hello Bryan,

    If by channels you mean lanes, the design I use is configured with two lanes for displayport. 

    My assumption of the training phase of displayport is that the controler start with a pattern emitted as HBR2 (5.4 Gbps) then switch to HBR if failing then RBR if failing again. Regarding the comment you mention, I'm thinking that because the adapter does not support HBR2, it would be drived with HBR or RBR automaticly after the training phase (but maybe I'm wrong about that). 

    Perhaps, modetest try only the HBR2 rate and should be modified to use HBR directly.

  • Hi LBO,
    If the DisplayPort lanes are configured correctly in the hw platform and likewise for Linux in the devicetree, you should see colorbars if you run the modetest command:
    # modetest -D fd4a0000.display -s 43:1920x1080@RG16
    Yes, we use modetest and PetaLinux for our tests.
    In order to see video on the attached monitor you will also need sw packages like X, matchbox, yavta, etc. installed in your root filesystem. Do you have these installed?
    You mentioned possibly purchasing a Ultra96-V2 board to test with. That is a good idea to have a known-good kit of hardware, Vivado hw platform, and PetaLinux BSP to start with.