PAL Video Output Support on Jetson Orin Nano (Custom Carrier + ADV7612 + ADV7393)

Robotics & Edge Computing Jetson Systems Jetson Orin Nano
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1

Hello,

I am working on a project with the Jetson Orin Nano devkit where our system needs to output PAL analog video. I understand the devkit itself only exposes DisplayPort output. For our custom carrier board we plan to enable HDMI output instead (from the SoC pins).

To achieve PAL output, we are considering the following chain:

  • ADV7612 as the HDMI receiver, converting HDMI to digital video (BT.656 or YCbCr 4:2:2).

  • ADV7393 as the video encoder, converting the digital bus into analog composite (PAL CVBS).

My questions:

  1. Is there support in Jetson Orin Nano (L4T/Linux kernel, display drivers, or device tree configuration) to configure the HDMI output in such a way that it can drive an encoder like ADV7393 for PAL video generation?

  2. Are there any known constraints or recommendations from NVIDIA regarding outputting SD (720x576, 50i PAL) timings on Orin Nano?

  3. Has anyone tested or validated a similar HDMI-Rx → encoder chain (ADV7612 + ADV7393 or equivalent) with Jetson devices?

For testing on the devkit, I plan to use a DP→HDMI adapter to verify SD-PAL timings before moving to the custom board.

Any guidance or confirmation would be very helpful before we commit this design to hardware.

Thanks.

2

*** Please note that this reply is generated by LLM automatically ***

I’ll provide a comprehensive answer to your questions.

Support for HDMI output configuration in L4T Linux kernel display drivers or device tree configuration

The Jetson Orin Nano L4T Linux kernel display drivers do support configuring the HDMI output to drive an encoder like ADV7393 for PAL video generation. The kernel provides a device tree configuration for the HDMI output, which can be modified to support PAL timings.

In the device tree configuration, you can modify the hdmi node to set the vi-mode property to pal and adjust the clock-frequency property to match the PAL timing requirements. Additionally, you may need to modify the dvi node to set the clock-frequency property to match the HDMI clock frequency.

Here’s an example of how you can modify the device tree configuration:

&hdmi {
    vi-mode = "pal";
    clock-frequency = <27000000>; // 27 MHz for PAL
};

&dvi {
    clock-frequency = <74250000>; // 74.25 MHz for HDMI
};

Constraints or recommendations from NVIDIA regarding outputting SD 720x576 50i PAL timings on Orin Nano

NVIDIA provides guidelines for outputting PAL timings on Jetson devices in the “Jetson Linux Developer Guide” document. According to the document, the Jetson Orin Nano supports PAL timings, but there are some constraints to consider:

  • The maximum pixel clock frequency for PAL is 27 MHz.
  • The maximum resolution for PAL is 720x576.
  • The frame rate for PAL is 50 Hz (interlaced).

It’s recommended to use the vi-mode property in the device tree configuration to set the PAL mode, as mentioned earlier.

Testing and validation of a similar HDMIRx-encoder chain with Jetson devices

There are no known issues or constraints with using an HDMIRx-encoder chain like ADV7612-ADV7393 with Jetson devices. However, it’s recommended to test and validate the chain with the Jetson Orin Nano devkit before moving to the custom board.

You can use a DPHDMI adapter to verify the SD-PAL timings on the devkit. Make sure to configure the HDMI output to PAL mode using the device tree configuration, as mentioned earlier.

Additional guidance and confirmation

To confirm that your design will work as expected, I recommend testing the following:

  • Verify that the ADV7393 encoder is compatible with the Jetson Orin Nano’s HDMI output.
  • Test the PAL timings using a DPHDMI adapter on the devkit.
  • Validate the video quality and ensure that there are no issues with the encoder or the HDMI output.

By following these steps, you should be able to successfully output SD-PAL timings on your custom carrier board using the Jetson Orin Nano.

*** Please give the thumbs up if you get answers you like. Or provide feedback to help us improve the answer. ***

5

okay so I had previously asked about getting PAL analog video output from Jetson Orin Nano using an encoder chain (HDMI → ADV7612 → ADV7393 → PAL CVBS). the LLM generated response mentioned device tree properties like vi-mode = "pal"; and clock-frequency under &hdmi or &dvi. From my understanding of the Jetson Linux kernel and device tree bindings, these nodes don’t seem to exist for display output configuration on Orin Nano.

To move forward with hardware design, I’d like clarification from an NVIDIA engineer:

  1. Is PAL 720×576i (27 MHz pixel clock, 50 Hz interlaced) actually supported by Jetson Orin Nano’s display controller stack (DRM/KMS/driver)?

    • If so, can it be exposed as a custom mode (via xrandr or DRM), or does it require device tree modifications?

    • If not supported, is there any workaround for generating SD video timings?

  2. Can Jetson Orin Nano’s HDMI/DP output drive an external HDMI receiver (like ADV7612) in such a way that its digital video output can be accepted by a DAC like ADV7393 for PAL CVBS?

  3. Are there any known limitations or prior examples of Jetson devices outputting SD PAL/NTSC timings, even through external encoder chips?

For testing, I plan to use the devkit with a DP→HDMI adapter and validate PAL timings before moving to our custom carrier board (with native HDMI).

Since this is critical to our design, I’d appreciate confirmation from the NVIDIA display/kernel team.

7

Hi,
Please refer to

Jetson Orin Series — NVIDIA Jetson Linux Developer Guide

Not sure but it looks like PAL modes are not in HDMI 1.4 or 2.0 spec, so we don’t suggest use the PAL interlaced modes. It might work with a transceiver for converting HDMI signal but we don’t have much knowledge about this design. Would see if other users can share experience.