# Displaying a single pixel on LED display showed two LEDs lit up

**URL:** <https://discourse.processing.org/t/displaying-a-single-pixel-on-led-display-showed-two-leds-lit-up/27009>\
**Category:** Processing\
**Created:** [January 13, 2021, 7:43am UTC](https://discourse.processing.org/t/displaying-a-single-pixel-on-led-display-showed-two-leds-lit-up/27009 "2021-01-13T07:43:31Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![mchangxe](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@mchangxe](https://discourse.processing.org/u/mchangxe)\
**Post date:** [January 13, 2021, 7:43am UTC](https://discourse.processing.org/t/displaying-a-single-pixel-on-led-display-showed-two-leds-lit-up/27009/1 "2021-01-13T07:43:31Z")

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In my processing program, I am setting just a single pixel to red, however on my LED screen, two LED lights lit up red, with one dimmer than the other. How can I make sure that only 1 LED light lights up?

I have set the processing P2D canvas to exactly the same size as the external display (at least i think the external display is indeed 2468 \* 64). Therefore I think that 1 pixel in processing should correspond to 1 led light on the screen. But this is clearly not the case now.

Thanks in advance.

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**Author:** ![TfGuy44](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/tfguy44/32/41_2.png) [@TfGuy44](https://discourse.processing.org/u/TfGuy44)\
**Post date:** [January 13, 2021, 10:01am UTC](https://discourse.processing.org/t/displaying-a-single-pixel-on-led-display-showed-two-leds-lit-up/27009/2 "2021-01-13T10:01:54Z")

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This might be because `smooth()` is on by default.

Try adding `noSmooth()` to `setup()` and see if that helps.

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**Author:** ![mchangxe](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@mchangxe](https://discourse.processing.org/u/mchangxe)\
**Post date:** [January 19, 2021, 9:38am UTC](https://discourse.processing.org/t/displaying-a-single-pixel-on-led-display-showed-two-leds-lit-up/27009/3 "2021-01-19T09:38:57Z")

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thanks, but i found that my LED display was actually not displaying at the resolution I thought it was.