72 lines
1.3 KiB
Markdown
72 lines
1.3 KiB
Markdown
# flashing heart blocks activity
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Control images with a variable.
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## ~avatar avatar
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In this activity, you will learn how to blink an image on the LED screen.
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## ~
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Let's start by adding code that plots a heart image on the screen using `show LEDs`. Once you are done coding, don't forget to run your code in the simulator or the @boardname@.
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```blocks
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basic.showLeds(`
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. # . # .
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# # # # #
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# # # # #
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. # # # .
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. . # . .`);
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```
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We want to leave the image on the screen for 0.5 seconds (500 milliseconds), then clear the screen. We can use `pause` to wait and `clear screen` to turn off the LEDs.
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```blocks
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basic.forever(() => {
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basic.showLeds(`
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. # . # .
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# # # # #
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# # # # #
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. # # # .
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. . # . .
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`)
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basic.pause(500)
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basic.clearScreen()
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})
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```
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Finally, we can surround this code with a `forever` loop to repeat it and add a pause after `clear screen` to keep the screen off for a little while. Modify your code so that your code looks like this.
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```blocks
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basic.forever(() => {
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basic.showLeds(`
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. # . # .
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# # # # #
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# # # # #
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. # # # .
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. . # . .
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`)
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basic.pause(500)
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basic.clearScreen()
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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](/lessons/flashing-heart/challenges)!
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## ~
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