HID Keyboard + brightness button USB Out

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shilpasonone04
Level 1
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I am designing HID Keyboard USB out data. On my keyboard, I want to add Brightness increment and Brightness Decrement keys. In my system brightness is controlled by Fn+f1 and Fn+f2, I am trying to implement this but my issue is there is no specific value for the Fn key. How can I implement the Brightness button on my keyboard? Thank you in Advance.

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Rakshith
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Rakshith
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250 likes received 1000 replies posted 750 replies posted

Hi @shilpasonone04

I found these threads that could help you with your query -  

https://stackoverflow.com/questions/24423724/finding-the-scan-code-of-fn-key

https://forum.arduino.cc/t/keyboardmodifier-for-function-key/656273/8

Thanks and Regards,
Rakshith M B
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Renate
Level 3
Level 3
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Fn is not a "real" key. The action is peeled off before it gets to the OS.

You'll want to use HID Consumer controls for Display Brightness Increment/Decrement, Usage Page 0xc, Usages 0x6f, 0x70. You'll need to make a separate HID report for that with a report ID.

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