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Thread: LED display - colors

  1. #1
    Senior Member Projectitis's Avatar
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    LED display - colors

    Hi all,

    Sorry, this isn't a Teensy question, but I'm hoping someone here might be able to help.

    I've put together some LED panels made up of SMD2121 LEDs and have a small HC-1w Wifi controller that displays images on the screen. Everything is basically working, except the images only display in about 4 levels of grayscale (each of R, G and B seem to only have 4 levels, or 2 bits per channel).

    Is this normal for LED displays? Am I correct in assuming this is a limitation of the controller, and not the panels? The controller advertises "64 gray levels" but obviously not. I've played around with all of the settings available, but am not able to make a difference so far.

    [EDIT] - It looks like that "64 levels of grayscale" might actually mean "64 colors", like the Sega Master System palette. I'll try and render that exact palette on screen and see if there is a match. That would mean 6-bit color as I suspected (2 bits per channel).

    Original image:
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    How it looks on the display:
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    Cheers,
    Peter

    p.s. Despite the low color levels, I've managed to get it looking pretty good with select images...
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    Last edited by Projectitis; 06-04-2021 at 11:06 AM.

  2. #2
    Senior Member
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    Yes, it's a limitation of the driver you're using. Something like a SmartMatrix can display thousands of colors with a Teensy: https://github.com/pixelmatix/SmartMatrix

  3. #3
    Senior Member Projectitis's Avatar
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    Thanks ecurtz. Wow, that library looks amazing! I have a spare T4 and a T4.1, but actually I've just received 10 ESP32 chips and this looks like a perfect project for that. The ESP32 has built-in bluetooth and wifi, so I don't need to worry about that.

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