F1/F2 Brightness for iOS

[balsman225]

I am trying to use an ESP32 to control a wall mounted iPad screen brightness (plan on pairing this library with MQTT).

On a normal Apple Bluetooth keyboard you can used F1 and F2 to adjust the brightness.
I have looked over Keyboard Modifier

I tried several combination without success
bleKeyboard.press(KEY_F1)
bleKeyboard.write(KEY_F1)
bleKeyboard.press(194)
bleKeyboard.write(194)
bleKeyboard.write(0xC2)

When testing with the "SendKeyStrokes" sketch I am able to get all other tests to work.
KEY_MEDIA_VOLUME_UP and KEY_MEDIA_VOLUME_DOWN work fine as well.

I'm curious if I need to create a custom "KEY_MEDIA" for brightness since iOS does not seem to be responding to F1/F2 keys

Thank you for the assistance
Also - Thank you for the great library

[T-vK]

Can you check if your keys are recognized in any way? https://www.keyboardtester.com/tester.html

[balsman225]

Thanks for the pointer - I looked over #3 and tested something out -
I changed the Volume increase and decrease to a custom brightness button.

I found the needed Hex for the Brightness Adjustment Link Here

For Brightness Up -

ESP32-BLE-Keyboard/BleKeyboard.cpp

Line 77 in 63e08b7

USAGE(1), 0xE9, // USAGE (Volume Increment) ; bit 5: 32

with

    USAGE(1),           0x006F,        //   USAGE (Brightness Up)       ; bit 5: 32

For Brightness Down -

ESP32-BLE-Keyboard/BleKeyboard.cpp

Line 78 in 63e08b7

USAGE(1), 0xEA, // USAGE (Volume Decrement) ; bit 6: 64

with

  USAGE(1),           0x0070,        //   USAGE (Brightness Down)     ; bit 6: 64

For Brightness Up -

ESP32-BLE-Keyboard/BleKeyboard.h

Line 68 in 63e08b7

const MediaKeyReport KEY_MEDIA_VOLUME_UP = {32, 0};

with

const MediaKeyReport KEY_MEDIA_BRIGHTNESS_UP = {32, 0};

For Brightness Down -

ESP32-BLE-Keyboard/BleKeyboard.h

Line 69 in 63e08b7

const MediaKeyReport KEY_MEDIA_VOLUME_DOWN = {64, 0};

with

const MediaKeyReport KEY_MEDIA_BRIGHTNESS_DOWN = {64, 0};

Once I added
bleKeyboard.write(KEY_MEDIA_BRIGHTNESS_UP)
and
bleKeyboard.write(KEY_MEDIA_BRIGHTNESS_DOWN)
to my test sketch It seems to be working great now.

This is all new to me so I don't know how to help added this to as a new media key in the library instead of stealing the volume entries but I would be happy to test for you if needed.

[T-vK]

I can't quite remember, but I think there was a reason why I only implemented a few media keys. Maybe it was a limitation in the hid descriptor or some kind of compatibility issue with the official Arduino USB keyboard library. If it was easy, I would of course have added way more, if not all media keys.
But thanks for sharing. This is probably gonna be useful to someone in the future.

[theguaz]

@balsman225 @T-vK Hello !, first of all nice work, I've found your solution while browsing for brightness control using BLe devices, I followed the changes u made in both files to basically swap the volume control with brightness control but so far when I swaped the values I only get volume control on iOS (iphone) but it behaves correctly on OSX (MacbookPro).

In CPP file:
//const MediaKeyReport KEY_MEDIA_VOLUME_UP = {32, 0};
//const MediaKeyReport KEY_MEDIA_VOLUME_DOWN = {64, 0};

const MediaKeyReport KEY_MEDIA_BRIGHTNESS_UP = {32, 0};
const MediaKeyReport KEY_MEDIA_BRIGHTNESS_DOWN = {64, 0};

In H file:
USAGE(1),           0xCD,          //   USAGE (Play/Pause)          ; bit 3: 8
USAGE(1),           0xE2,          //   USAGE (Mute)                ; bit 4: 16
USAGE(1),           0x006F,        	//   USAGE (Bright Increment)    ; bit 5: 32
USAGE(1),           0x0070,        	//   USAGE (Bright Decrement)    ; bit 6: 64
USAGE(2),           0x23, 0x02,    //   Usage (WWW Home)            ; bit 7: 128

The hexadecimal needs to be edited somewhere else in order to trigger brightness?
Thank you in advance :)

[TanjuDuygu]

Hi balsman.

You are on the right way

USAGE(1), 0x006F, // USAGE (Bright Increment) ; bit 5: 32
USAGE(1), 0x0070, // USAGE (Bright Decrement) ; bit 6: 64

You need just need unpair (forget device on your iphone bluetoot menu) and again pair your bluetooth device on your iphone. I treid %100 working birightness on my iphone and ipad. If you din't refresh pair still stick working just volume up and down.
Good luck

[and7ey]

@balsman225 sorry for off top question - is it possible to switch off the iOS screen with ESP32 keyboard? or to lock the iPad?