Following are the steps for flashing heart in the micro:bit's LED
Click this link https://microbit.org/
Then click on official code editor Microsoft Make Code to do programming
Then click on New Project and give project name as Flashing Heart then this window will display
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4. From Basic drag and drop Show Leds block in the forever block and draw heart shape on it.
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5. If you have a micro:bit connected into laptop/pc/mobile using USB cable, Click on download button to transfer your code (hex file) and see the result
6. The result is shown below: it will flashing heart on led
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