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+# KBD firmware
+
+## How to build
+Get src of `qmk/qmk_firmware` and `vial-kb/vial-qmk` first
+```sh
+make git-submodule
+```
+
+### VIA
+
+```sh
+make qmk-clean
+kb=crkbd make qmk-init
+kb=crkbd kr=rev4/standard km=via make qmk-compile
+```
+A built data will be stored on `keyboards/crkbd/qmk/qmk_firmware/.build`\
+Please change `kb`, `kr` and `km` when build other.
+
+### Vial
+```sh
+make vial-qmk-clean
+kb=crkbd make vial-qmk-init
+kb=crkbd kr=rev4/standard km=vial make vial-qmk-compile
+```
+A built data will be stored on `keyboards/crkbd/vial-kb/vial-qmk/.build`\
+Please change `kb`, `kr` and `km` when build other.
+
+### All clean and build
+```sh
+make git-submodule
+```