**NOTE:** To abort a make command press `Ctrl-c`
-For more details on the QMK build process see [Make Instructions](Make-Instructions).
+For more details on the QMK build process see [Make Instructions](/Make-Instructions.md).
### Simple instructions for building and uploading a keyboard
* Build all Clueboard keymaps: `make clueboard`
* Build the default Planck keymap: `make planck-rev4-default`
-* Build and flash your ergodox-ez: `make ergodox-ez-default-teensy`
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+* Build and flash your ergodox-ez: `make ergodox-ez-default-teensy`
+
+# The `config.h` file
+
+There are 2 `config.h` locations:
+
+* keyboard (`/keyboards/<keyboard>/`)
+* keymap (`/keyboards/<keyboard>/keymaps/<keymap>/`)
+
+The keyboard `config.h` is included only if the keymap one doesn't exist. The format to use for your custom one [is here](https://github.com/qmk/qmk_firmware/blob/master/doc/keymap_config_h_example.h). If you want to override a setting from the parent `config.h` file, you need to do this:
+
+```c
+#undef MY_SETTING
+#define MY_SETTING 4
+```
+
+For a value of `4` for this imaginary setting. So we `undef` it first, then `define` it.
+
+You can then override any settings, rather than having to copy and paste the whole thing.
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