1.**Toolchain** On Windows install [Atmel AVR Toolchain][atmelgcc] for AVR GCC compiler and [Cygwin][cygwin](or [MinGW][mingw]) for shell terminal. On Mac you can use [CrossPack][crosspack] or your favorite package manager. On Linux you can install AVR GCC with your favorite package manager.
3.**Driver** On Windows you start DFU bootloader on the chip first time you will see 'Found New Hardware Wizard' to install driver. If you install device driver properly you can find chip name like 'ATmega32U4' under 'LibUSB-Win32 Devices' tree on 'Device Manager'. If not you shall need to update its driver on 'Device Manager'. You will find the driver in `FLIP` install directory like: C:\Program Files (x86)\Atmel\Flip 3.4.5\usb\. In case of `dfu-programmer` use its driver.
Open terminal window to get access to commands. Use Cygwin(or MingGW) `shell terminal` in Windows or `Terminal.app` on Mac OSX. In Windows press `Windows` key and `R` then enter `cmd` in 'Run command' dialog showing up.
cd tmk_keyboard/{'keyboard' or 'converter'}/<project>
### 3. Make
Build firmware using GNU `make` command. You'll see `<project>_<variant>.hex` file in that directory unless something unexpected occurs in build process.
Now you have **hex** file to program on current directory. This **hex** is only needed to program your controller, other files are used for development and you may leave and forget them.
### 1. Start bootloader
How to program controller depends on controller chip and its board design. To program AVR USB chips you'll need to start it up in bootloader mode. Most of boards with the chip have a push button to let bootloader come up. Consult with your controller board manual.
Stock AVR USB chips have DFU bootloader by factory default. `FLIP` is a DFU programmer on Windows offered by Atmel. Open source command line tool `dfu-programmer` also supports AVR chips, it runs on Linux, Mac OSX and even Windows.
3. On menu bar click File -> Load HEX File, then select your firmware hex file on File Selector dialog.
4. On 'Operations Flow' panel click 'Run' button to load the firmware binary to the chip. Note that you should keep 'Erase', 'Blank Check', 'Program' and 'Verify' check boxes selected.
5. Re-plug USB cord or click 'Start Application' button to restart your controller.
You may want to use other programmer like `avrdude` with AVRISPmkII, Arduino or USBasp. In that case you can still use make target `program` for build with configuring `PROGRAM_CMD` in Makefile.
Optional. Set proper command for your controller, bootloader and programmer. This command can be used with `make program`. Not needed if you use `FLIP`, `dfu-programmer` or `Teensy Loader`.