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docs/reference/js/lessons/flashing-heart/activity.md

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+# flashing heart activity
+
+Ccontrol images with variables.
+
+### ~avatar avatar
+
+### @video td/videos/flashing-heart-0
+
+In this activity, you will learn how to blink an image on the LED screen.
+
+### ~
+
+To create a new script, go to the [Create Code](https://www.microbit.co.uk/create-code) page and tap `New Project` under **KindScript**.
+
+Let's start by adding code that plots a heart image on the screen using `basic->plot image`. Once you are done coding, don't forget to run your code in the simulator or the BBC micro:bit.
+
+```
+basic.plotImage(`
+. # . # .
+# # # # #
+# # # # #
+. # # # .
+. . # . .
+`) // ***
+```
+
+We want to leave the image on the screen for 0.5 seconds (500 milliseconds), then clear the screen. We can use `basic->pause` to wait and `basic->clear screen` to turn off the LEDs.
+
+```
+basic.plotImage(`
+. # . # .
+# # # # #
+# # # # #
+. # # # .
+. . # . .
+`)
+basic.pause(500) // ***
+basic.clearScreen() // ***
+```
+
+Finally, we can surround this code with a `basic->forever` loop to repeat it and add a pause after `basic->clear screen` to keep the screen off for a little while. Modify your code so that your code looks like this.
+
+```
+basic.forever(() => {
+    basic.plotImage(`
+. # . # .
+# # # # #
+# # # # #
+. # # # .
+. . # . .
+`)
+    basic.pause(500)
+    basic.clearScreen()
+    basic.pause(500)
+})
+```
+
+### ~avatar boothing
+
+Excellent, you're ready to continue with the [challenges](/microbit/lessons/flashing-heart/challenges)!
+
+### ~
+