HDMI output with jetpack 6.2.1

Robotics & Edge Computing Jetson Systems Jetson Orin NX
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Our carrier board uses DP so these pins will be configured for DP_AUX. In pinmux you can change these to I2C.

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For a custom carrier board design you will need to follow the design guide and compare it for any differences on your end. You will also need pull up on both sides of the level shifter for I2C signals on the Jetson Module side and the HDMI connector side. Refer to the carrier board design files for detailed schematics. Jetson Orin Nano Developer Kit Carrier Board Reference Design Files https://developer.nvidia.com/downloads/assets/embedded/secure/jetson/orin_nano/docs/jetson_orin_nano_devkit_carrier_board_reference_design_files_a04_20230320.zip/

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That was the solution.

I added pull-up resistors to pins 98 and 100. I finally saw I2C communication once the hotplug was activated.
After reconnecting all the signals, HDMI is now working properly.

The hotplug was correctly configured, but HDMI was blocked at the I2C communication level.

Out of curiosity, how are pins 98 and 100 configured ? I am surprised that they do not have internal pull-up resistors. When these pins are left floating, the I2C communication is not visible and there are no logs. Does the Jetson perform a read on these pins before actually using them ?

Thank you very much for your help.

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I can’t speak for whoever actually designed it, but adding a pull-up or pull-down potentially increases power consumption. Also, on an embedded system intended to use a custom carrier board of unknown requirements, it seems logical to not include those resistors on the module itself. Most of what you see is more or less a reference and not intended for a final product (the custom carrier board in combination with a commercial module is what one should find in final products).