No HDMI output

[sam.a...@gmail.com]

Hi,

I have a custom board based on beaglebone's design. I have HDMI output going from TDA19988 directly to TS3DV642. TS3DV642 is being used as a switch between two HDMI sources. One HDMI source is coming from TDA19988 and the other source is coming from a laptop. I am able to switch between the sources, and I can see the output from my laptop's HDMI on a monitor. I am not getting HDMI output on a monitor from TDA19988 side. On my oscilloscope I can see all the HDMI signals at the output of TDA19988, which are very similar to the laptop's HDMI signals. 

HDMI differential pairs coming from TDA19988 have 100ohm impedance. 

I am not sure if its something in the linux image that I have to active or is it something in the hardware that's causing this issue.

Before this custom board, the design was tested on Beaglebone with TS3DV642EVM and it worked fine. The only thing that changed in custom board is I removed micro HDMI connector and routed HDMI differential pairs to TS3DV642.

I would really appreciate any kind of help.

Thank you,

[Robert Nelson]

So how does "beagle clone" device read the end display's edid register
in your design to know what resolution/etc to transmit?

If the answer to that, is it doesn't...

Then you need to force the hdmi output..

aka something similar to this, passed thru /proc/cmdline on bootup..

video=HDMI-A-1:1024x768@60e

Regards,

--
Robert Nelson
https://rcn-ee.com/

[sam.a...@gmail.com]

Hi Robert,

It worked!! I got the display! Thank you so so much!

The only thing is colors are kind of funky. Beagleboard.org and the beagle image on the wallpaper is kind of bluish. How can I get correct colors?

Thank you

[sam.a...@gmail.com]

Hi Robert,

For some reason on my display blue and red colors are inverted. How can I fix it?

Thank you

On Thursday, August 23, 2018 at 3:54:03 PM UTC-6, RobertCNelson wrote: