Firmware-only Keycodes
Firmware only keycodes are keycodes that modify the behavior of the keyboard firmware and are processed to send something different.
Layers​
These keycodes are used by the firmware to switch from one layer to another.
| Usage ID (HEX) | Usage Name | Keycode Identifiers |
|---|---|---|
| 0xF0 | Access Layer 0 (default) | LAYER_0 |
| 0xF1 | Access Layer 1 (default) | LAYER_1 |
| 0xF2 | Access Layer 2 (default) | LAYER_2 |
| 0xF3 | Access Layer 3 (default) | LAYER_3 |
| 0xF4 | Access Layer 4 (default) | LAYER_4 |
| 0xF5 | Access Layer 0 (default) | LAYER_5 |
| 0xF6 | Access Layer 1 (default) | LAYER_6 |
| 0xF7 | Access Layer 2 (default) | LAYER_7 |
| 0xF8 | Access Layer 3 (default) | LAYER_8 |
| 0xF9 | Access Layer 4 (default) | LAYER_9 |
| 0xFA | Access Layer 4 (default) | LAYER_A |
| 0xFB | Access Layer 0 (default) | LAYER_B |
| 0xFC | Access Layer 1 (default) | LAYER_C |
| 0xFD | Access Layer 2 (default) | LAYER_D |
| 0xFE | Access Layer 3 (default) | LAYER_E |
| 0xFF | Access Layer 4 (default) | LAYER_F |
If you want to activate a layer by pressing a combination of two other layer keycodes, you can use the function process_user_layers to define the behavior you want.
You will need to add the following two lines to your keymap.h
#define USER_LAYER_FUNCTION 0
void process_user_layers(uint16_t layermask);
You will also need to define which two layer activate the 3rd one. This is done by adding a few lines in keymap.cpp
void process_user_layers(uint16_t layermask)
{
KeyScanner::process_for_tri_layers(_L1, _L2, _L3);
}
In the example above, both LAYER_1 and LAYER_2 need to be pressed for LAYER_3 to be activated.
Note that _L1, _L2 and _L3 are not keycodes.
If combinations with more layers are needed, you can add them in that function.
Page is still a work in progress. Refer to hid_keycodes.h and advanced_keycodes.h for a detailed list of keycodes.