Support for multimedia keys

[biemster]

The current implementation only supports alphanumeric and KBD keys as defined from here on further:

3keys_1knob/include/usb_conkbd.h

Line 41 in 5f5ef65

// Special keys

There are a few consumer keys that would be very handly (for example volume up/down) defined from here on:

3keys_1knob/include/usb_conkbd.h

Line 82 in 5f5ef65

// Consumer Keyboard Keycodes

Support for those would be much appreciated, but would require some rework of the internals. Especially the storage in and reading from EEPROM.

[eworm-de]

Indeed, that would be nice to have...

[eworm-de]

I had a brainstorm and hacking session with @mgisbers...

This is the official documentation: USB HID Usage Tables - Keyboard/Keypad Page
... which gives a nice table with ids to be written into KBD_report.

The idea on this: We ditch the ASCII to keycode mapping, as it interferes with some generic codes we want to send. After all one should be able to look up an id in a table if the same person is expected to write that id to a file with a hex editor. 😜

The eeprom layout is changed to two bytes for every key:

• first byte is a bitmap of modifiers (control, shift, alt, ...)
• second byte is the usage id found in table

Let's have some examples:

• a → 0x0004
• A (capital a) → 0x0204
• Ctrl+Alt+Del → 0x054c
• Volume up → 0x0080
• Volume down → 0x0081

Any thoughts on this?

[eworm-de]

I've come up with a prove of concept...
https://github.com/eworm-de/3keys_1knob/tree/modifier-and-code

[biemster]

Yeah that looks nice! I was also thinking about a 2 byte layout indeed, and even a bit more elaborate since I was considering having the pad send whole sequences. So maybe the first byte can also indicate how many ids are coming?
I have to be honest though that my free time is very limited at the moment, and this project is not really high on my list, sorry.

[eworm-de]

Yes, sequences of keys (macros) would be nice... Already thinking about it.

[MrGeorgeK55]

i'm having problems with the Consumer Keyboard Keycodes, do you need a modifier in the first byte? or i'm missing something?

[biemster]

@MrGeorgeK55 instead of KBD_{press,releaseAll} here

3keys_1knob/3keys_1knob.c

Line 195 in 5f5ef65

KBD_press(currentKnobKey); // press corresponding key ...

and here

3keys_1knob/3keys_1knob.c

Line 198 in 5f5ef65

KBD_releaseAll(); // ... or release last key

you need CON_{press,releaseAll}.

[hugokernel]

Thank you @eworm-de: Your branch works perfectly well, however, I had to make a horrible hack to be able to send the Mute keycode via the consumer functions.

I can't wait for this project to evolve a bit.

[biemster]

I can't wait for this project to evolve a bit.

Winter is coming, and with that more indoors time so this ticket will be picked up at some point.

[hugokernel]

• Ctrl+Alt+Del → 0x054c

Could you explains how you get 0x054c ?

I want to send this: Ctrl + Win + l but I don't really understand how I can do that.

Edit: Bitmap is ?|?|?|?|WIN|CTRL|SHIFT|ALT

[MisterRager]

I wanted to also add support for the consumer page keys, so I added a third configuration byte in eeprom per-key:
eworm-de#1

[MrGeorgeK55]

• Ctrl+Alt+Del → 0x054c

Could you explains how you get 0x054c ?

I want to send this: Ctrl + Win + l but I don't really understand how I can do that.

Edit: Bitmap is ?|?|?|?|WIN|CTRL|SHIFT|ALT

So far with the results of my tests, this is the table of modifier keys:

00 None
01 Ctrl
02 Shift
03 Ctrl + Shift
04 Alt
05 Ctrl + Alt
06 Shift + Alt
07 Ctrl + Shift + Alt

[MrGeorgeK55]

Also i Modified the code for a different project: Macropad 8 Keys based on CH552g, working with Keyboard keys. Consumer keys and macros up to 10 keys. im working to adapt it to this keyboard

[MrGeorgeK55]

Came with a proof of concept of macros up to 19 consecutive keys (without any modifier by now), also with more documentation.
Macropad-3-Keys-1-Knob

[biemster]

nice work @MrGeorgeK55! I'll gave a closer look soon when time allows