Jetson Nano Custom Carrier Board - No HDMI

I have designed a custom carrier board that is almost identical to Nvidias carrier board for the Jetson Nano. I can’t get the HDMI to work at all. There appears to be SDA and SCL signals for communication from the SOM but there are no data signals. The monitor does not appear to detect my device. The only difference is that I used mini HDMI instead of regular HDMI.

Can you share the schematic of HDMI part for checking? In general, it should be able to work if you follow the design guide well.

Here is the schematic for the HDMI. As you can see, it is almost exactly the same as the Nvidia carrier. After several days of investigating, we cannot figure out why it isn’t working. Any help would be appreciated.

Is it connected to DP1 port of module connector? It looks same to reference. Do you have log info of it?

Also, did you observe the HPD action when HDMI device plug in?

Hello. Do you got B01 Jetson of A02 Jetson? And which documentation you have used for making custom board? If official docs, then it is because you got docs for B01 and used A02 Jetson. I got this problem to, but with ethernet port.

Here is the schematic page where the HDMI is connected to the Nano.

We did observe the HPD action when we plugged and unplugged the HDMI. When the cable is plugged in, the HDMI_HPD pin is pulled low because the transistor (Q4) is on. When the cable is not plugged in, Q4 is off and the HPD pin is pulled high to 1.8V. The data sheet says that for a display port the HPD needs to be non-inverting, but it doesn’t say anything for the HDMI HPD.

Any log info?

Here is my bootup log:

JetsonNano_Boot_Log.txt (30.1 KB)


Please share the dmesg too. Your boot up log does not have kernel log.

There is no update from you for a period, assuming this is not an issue any more.
Hence we are closing this topic. If need further support, please open a new one.

Hi abby,kitchen,

Have you clarified the cause and resolved the issue?
Any result can be shared?

I almost screwed up my carrier board HDMI design by using mini-HDMI and realizing last moment that connector pinout is different from standard HDMI.
I’m not saying yours isn’t correct, but it’s an easy check :)
Good luck!