56 lines
1.3 KiB
Markdown
56 lines
1.3 KiB
Markdown
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# blink activity
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Turn an LED on and off with forever
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### ~avatar avatar
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### @video td/videos/blink-0
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Let's learn how to blink an LED.
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### ~
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Have you ever tried to blink a flashlight at night? The concept is fairly simply: turn on the light, wait for a little, turn off the light, wait again, and repeat. That's exactly what we need to code to get a blinking LED.
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Let's start by adding a line of code that turns on the LED at position ``2, 2``.
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```
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led.plot(2, 2)
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```
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Run your script to make sure it's correct. Then, let's add code to **pause** `500` milliseconds and turn off the LED.
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```
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led.plot(2, 2)
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basic.pause(500)
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led.unplot(2, 2)
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```
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We've got the LED blinking once. Let's add another pause and turn on the LED again.
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```
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led.plot(2, 2)
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basic.pause(500)
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led.unplot(2, 2)
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basic.pause(500)
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led.plot(2, 2)
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```
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The current code works but it only blinks once! We are going to use a `basic->forever` loop and move the code inside it to repeat it forever. We've dropped the second `led-plot` line since we don't need it in the loop.
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```
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basic.forever(() => {
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led.plot(2, 2)
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basic.pause(500)
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led.unplot(2, 2)
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basic.pause(500)
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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/blink/challenges)!
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### ~
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