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Reverse-engineering a $35 backup camera display (AMT630A)

83 points · 25 comments · mogrinz

  1. mogrinz · · focus · HN ↗
    This started because I built a full-size Robby the Robot suit and discovered I couldn&#x27;t actually see out of it (<a href="https:&#x2F;&#x2F;youtu.be&#x2F;gAHd46ErNA8?si=-iOwbobp4trPXdGB" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;gAHd46ErNA8?si=-iOwbobp4trPXdGB)

    I bought a $35 backup camera&#x2F;display to solve that problem, then discovered that the display contained an AMT630A video processor with a surprisingly capable OSD system. That sent me down a rabbit hole of I2C probing, firmware dumping, register tracing, custom graphics, bitmap formats, hidden factory menus, and eventually figuring out how to use an ESP32 to generate a programmable HUD over the live composite video.

    I ended up turning what I learned into an Arduino library, which I&#x27;ve released on GitHub. It supports built-in and custom fonts, multiple OSD windows, 16-color bitmaps, palettes, transparency, and animation. It can also be used with composite video sources other than the camera.

    The library and code are here: <a href="https:&#x2F;&#x2F;github.com&#x2F;mogrinz&#x2F;AMT630A" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;mogrinz&#x2F;AMT630A You can also install directly from the Arduino IDE Library Manager (search for AMT630A)

    1. netsharc · · focus · HN ↗
      Hah, the video is more exciting than the readme, IMO an image of the robot in the readme would be attention-getting.

      Would &quot;rear view mirrors&quot; help navigation in the suit? So 2 extra displays that would give you a view of what&#x27;s over your shoulder, like on some cars nowadays (for example): <a href="https:&#x2F;&#x2F;www.carscoops.com&#x2F;2022&#x2F;02&#x2F;heres-what-you-wanted-to-know-about-the-honda-e&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.carscoops.com&#x2F;2022&#x2F;02&#x2F;heres-what-you-wanted-to-k...

      1. jakzurr · · focus · HN ↗
        Holy smokes I like that. Maybe it will catch on, I dunno.
        1. netsharc · · focus · HN ↗
          Cameras are rear view mirrors? Audi e-trons have them, they&#x27;re also available as option on Hyundai Ioniqs. But apparently it&#x27;s unlawful to not have physical side mirrors in North America...
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