Your keyboard can make sounds! If you've got a Planck, Preonic, or basically any AVR keyboard that allows access to certain PWM-capable pins, you can hook up a simple speaker and make it beep. You can use those beeps to indicate layer transitions, modifiers, special keys, or just to play some funky 8bit tunes.
Up to two simultaneous audio voices are supported, one driven by timer 1 and another driven by timer 3. The following pins can be defined as audio outputs in config.h:
If you add `AUDIO_ENABLE = yes` to your `rules.mk`, there's a couple different sounds that will automatically be enabled without any other configuration:
```
STARTUP_SONG // plays when the keyboard starts up (audio.c)
GOODBYE_SONG // plays when you press the RESET key (quantum.c)
AG_NORM_SONG // plays when you press AG_NORM (quantum.c)
AG_SWAP_SONG // plays when you press AG_SWAP (quantum.c)
MUSIC_ON_SONG // plays when music mode is activated (process_music.c)
MUSIC_OFF_SONG // plays when music mode is deactivated (process_music.c)
CHROMATIC_SONG // plays when the chromatic music mode is selected (process_music.c)
GUITAR_SONG // plays when the guitar music mode is selected (process_music.c)
VIOLIN_SONG // plays when the violin music mode is selected (process_music.c)
MAJOR_SONG // plays when the major music mode is selected (process_music.c)
```
You can override the default songs by doing something like this in your `config.h`:
```c
#ifdef AUDIO_ENABLE
#define STARTUP_SONG SONG(STARTUP_SOUND)
#endif
```
A full list of sounds can be found in [quantum/audio/song_list.h](https://github.com/qmk/qmk_firmware/blob/master/quantum/audio/song_list.h) - feel free to add your own to this list! All available notes can be seen in [quantum/audio/musical_notes.h](https://github.com/qmk/qmk_firmware/blob/master/quantum/audio/musical_notes.h).
To play a custom sound at a particular time, you can define a song like this (near the top of the file):
```c
float my_song[][2] = SONG(QWERTY_SOUND);
```
And then play your song like this:
```c
PLAY_SONG(my_song);
```
Alternatively, you can play it in a loop like this:
```c
PLAY_LOOP(my_song);
```
It's advised that you wrap all audio features in `#ifdef AUDIO_ENABLE` / `#endif` to avoid causing problems when audio isn't built into the keyboard.
!> These keycodes turn all of the audio functionality on and off. Turning it off means that audio feedback, audio clicky, music mode, etc. are disabled, completely.
For ARM devices, you can adjust the DAC sample values. If your board is too loud for you or your coworkers, you can set the max using `DAC_SAMPLE_MAX` in your `config.h`:
The music mode maps your columns to a chromatic scale, and your rows to octaves. This works best with ortholinear keyboards, but can be made to work with others. All keycodes less than `0xFF` get blocked, so you won't type while playing notes - if you have special keys/mods, those will still work. A work-around for this is to jump to a different layer with KC_NOs before (or after) enabling music mode.
The pitch standard (`PITCH_STANDARD_A`) is 440.0f by default - to change this, add something like this to your `config.h`:
#define PITCH_STANDARD_A 432.0f
You can completely disable Music Mode as well. This is useful, if you're pressed for space on your controller. To disable it, add this to your `config.h`:
By default, `MUSIC_MASK` is set to `keycode < 0xFF` which means keycodes less than `0xFF` are turned into notes, and don't output anything. You can change this by defining this in your `config.h` like this:
#define MUSIC_MASK keycode != KC_NO
Which will capture all keycodes - be careful, this will get you stuck in music mode until you restart your keyboard!
For a more advanced way to control which keycodes should still be processed, you can use `music_mask_kb(keycode)` in `<keyboard>.c` and `music_mask_user(keycode)` in your `keymap.c`:
bool music_mask_user(uint16_t keycode) {
switch (keycode) {
case RAISE:
case LOWER:
return false;
default:
return true;
}
}
Things that return false are not part of the mask, and are always processed.
By default, the Music Mode uses the columns and row to determine the scale for the keys. For a board that uses a rectangular matrix that matches the keyboard layout, this is just fine. However, for boards that use a more complicated matrix (such as the Planck Rev6, or many split keyboards) this would result in a very skewed experience.
To enable this feature, add `#define MUSIC_MAP` to your `config.h` file, and then you will want to add a `uint8_t music_map` to your keyboard's `c` file, or your `keymap.c`.
You will want to use whichever `LAYOUT` macro that your keyboard uses here. This maps it to the correct key location. Start in the bottom left of the keyboard layout, and move to the right, and then upwards. Fill in all the entries until you have a complete matrix.
You can look at the [Planck Keyboard](https://github.com/qmk/qmk_firmware/blob/e9ace1487887c1f8b4a7e8e6d87c322988bec9ce/keyboards/planck/planck.c#L24-L29) as an example of how to implement this.
This adds a click sound each time you hit a button, to simulate click sounds from the keyboard. And the sounds are slightly different for each keypress, so it doesn't sound like a single long note, if you type rapidly.
*`CK_TOGG` - Toggles the status (will play sound if enabled)
| `AUDIO_CLICKY_FREQ_FACTOR` | 1.18921f| Sets the stepping of UP/DOWN key codes. This is a multiplicative factor. The default steps the frequency up/down by a musical minor third. |
| `AUDIO_CLICKY_FREQ_RANDOMNESS` | 0.05f | Sets a factor of randomness for the clicks, Setting this to `0f` will make each click identical, and `1.0f` will make this sound much like the 90's computer screen scrolling/typing effect. |
| `AUDIO_CLICKY_DELAY_DURATION` | 1 | An integer note duration where 1 is 1/16th of the tempo, or a sixty-fourth note (see `quantum/audio/musical_notes.h` for implementation details). The main clicky effect will be delayed by this duration. Adjusting this to values around 6-12 will help compensate for loud switches. |
