+If your target is **HHKB JP** you need to set `HHKB_JP` build option in `Makefile` or use `Makefile.jp` instead of `Makefile`.
+
+If you use other than **TMK Alt Controller Board** set proper `MCU`, `BOOTLOADER_SIZE` and other build options in `Makefile` and `config.h`. At least PJRC Teensy requires changing `BOOTLOADER_SIZE` to 512.