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docs/lessons/flashing-heart/activity.md

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+# flashing heart blocks activity
+
+Control images with a variable.
+
+### ~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](/microbit/create-code) page and tap *New Project* under *Block Editor*.
+
+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 micro:bit.
+
+
+```blocks
+basic.showLeds(`
+. # . # .
+# # # # #
+# # # # #
+. # # # .
+. . # . .`);
+```
+
+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.
+
+
+```blocks
+basic.forever(() => {
+    basic.showLeds(`
+        . # . # .
+        # # # # #
+        # # # # #
+        . # # # .
+        . . # . .
+        `)
+    basic.pause(500)
+    basic.clearScreen()
+})
+
+
+```
+
+
+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.
+
+
+```blocks
+basic.forever(() => {
+    basic.showLeds(`
+        . # . # .
+        # # # # #
+        # # # # #
+        . # # # .
+        . . # . .
+        `)
+    basic.pause(500)
+    basic.clearScreen()
+    basic.pause(500)
+
+})
+
+
+
+```
+
+
+### ~avatar boothing
+
+Excellent, you're ready to continue with the [challenges](/microbit/lessons/flashing-heart/challenges)!
+
+### ~
+