46 lines
1.2 KiB
Markdown
46 lines
1.2 KiB
Markdown
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# night light activity
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change the brightness of the BBC micro:bit. #docs #tutorials #stepByStep
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### ~avatar avatar
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### @video td/videos/night-light-0
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Welcome! This tutorial will teach you how to change the brightness of the BBC micro:bit. Let's get started!
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### ~
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The brightness of the LED screen can be changed by using the `led->set brightness` function. This function takes a number between ``0`` (off) and ``255`` (full brightness).
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Let's build a little app that dims the screen when pressing button ``A``.
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Add the code `led->plot all` to turn on all the LEDs. Don't hesitate to run your code to see what happens.
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```
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led.plotAll() // ***
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```
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The screen starts with a 50% brightness value by default (128). Add a new line of code to set the full brightness (255) using `led->set brightness`.
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```
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led.setBrightness(255) // ***
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led.plotAll()
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```
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Add a new event handler for `input->on button pressed(A)` and add the code to set the brightness to `64`.
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```
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led.setBrightness(255)
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led.plotAll()
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input.onButtonPressed("A", () => {
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led.setBrightness(64) // ***
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}) // ***
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```
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### ~avatar boothing
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Excellent, you're ready to continue with the [challenges](/microbit/lessons/night-light/challenges)!
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### ~
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