1. Install [MHV AVR Tools](https://github.com/jackhumbert/qmk_firmware). Disable smatch, but **be sure to leave the option to add the tools to the PATH checked**.
2. Install [MinGW](https://sourceforge.net/projects/mingw/files/Installer/mingw-get-setup.exe/download). During installation, uncheck the option to install a graphical user interface. **DO NOT change the default installation folder.** The scripts depend on the default location.
3. Clone this repository. [This link will download it as a zip file, which you'll need to extract.](https://github.com/jackhumbert/qmk_firmware/archive/master.zip) Open the extracted folder in Windows Explorer.
4. Right-click on the 1-setup-path-win batch script, select "Run as administrator", and accept the User Account Control prompt. Press the spacebar to dismiss the success message in the command prompt that pops up.
5. Right-click on the 2-setup-environment-win batch script, select "Run as administrator", and accept the User Account Control prompt. This part may take a couple of minutes, and you'll need to approve a driver installation, but once it finishes, your environment is complete!
Unlike the other keymaps, prefixing the keycodes with `KC_` is required. A full list of the keycodes is available [here](https://github.com/jackhumbert/qmk_firmware/blob/master/tmk_core/doc/keycode.txt). For the keycodes available only in the extended keymap, see this [header file](https://github.com/jackhumbert/qmk_firmware/blob/master/quantum/keymap_common.h).
The extended keymap extends the number of function layers from 32 to the near-infinite value of 256. Rather than using `FN<num>` notation (still available, but limited to `FN0`-`FN31`), you can use the `FUNC(<num>)` notation. `F(<num>)` is a shortcut for this.
The function actions are unchanged, and you can see the full list of them [here](https://github.com/jackhumbert/tmk_keyboard/blob/master/common/action_code.h). They are explained in detail [here](https://github.com/jackhumbert/tmk_keyboard/blob/master/doc/keymap.md#2-action).
Macros have been setup in the `keymaps/keymap_default.c` file so that you can use `M(<num>)` to access a macro in the `action_get_macro` section on your keymap. The switch/case structure you see here is required, and is setup for `M(0)` - you'll need to copy and paste the code to look like this (e.g. to support `M(3)`):
`MACRODOWN()` is a shortcut for `(record->event.pressed ? MACRO(__VA_ARGS__) : MACRO_NONE)` which tells the macro to execute when the key is pressed. Without this, the macro will be executed on both the down and up stroke.