Make example for this keyboard (after setting up your build environment):
make kj_modify/rs40:default
Flashing example for this keyboard:
make kj_modify/rs40:default:flash
See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
## Bootloader
Enter the bootloader in 3 ways:
* **Bootmagic reset**: Hold down the key at (0,0) in the matrix (usually the top left key or Escape) and plug in the keyboard
* **Physical reset button**: Briefly press the button on the back of the PCB - some may have pads you must short instead
* **Keycode in layout**: Press the key mapped to `QK_BOOT` if it is available