Keyestudio KS4028 Manual page 174

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The 20 in the code is an arbitrary value of light intensity. If the current light
level is less than or equal to 20, the icon moon will appear on the LED dot
matrix. If it's bigger than 20, the sun will appear.
If you're running Windows 7 or 8 instead of Windows 10, via Google
Chrome won't be able to match devices. You'll need to use the CoolTerm
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