doc: application: improve Kconfig setting documentation
Now that the above sections more clearly define the behavior of
CONF_FILE, the section on writing a .conf can be cleaned up and made
into a simple primer on syntax.
Signed-off-by: Marti Bolivar <marti@opensourcefoundries.com>
diff --git a/doc/application/application.rst b/doc/application/application.rst
index 2a39b37..648b0f5 100644
--- a/doc/application/application.rst
+++ b/doc/application/application.rst
@@ -355,43 +355,50 @@
For information on available kernel configuration options, including
inter-dependencies between options, see the :ref:`configuration`.
-Application Configuration
-=========================
+Setting Application Configuration Values
+========================================
-As described above, an application can use :makevar:`CONF_FILE` to
-override its default kernel configuration.
+This section describes how to edit Zephyr configuration
+(:file:`.conf`) files.
-#. Navigate to the :file:`app`, and create the :file:`prj.conf` file. Enter:
+- Add each configuration entry on a new line.
- .. code-block:: bash
+- Enable a boolean option by setting its value to ``y``:
- $ vim prj.conf
+ .. code-block:: none
- The application's default configuration is specified by
- ``CONF_FILE``, ``CONF_FILE`` defaults to :file:`prj.conf` unless
- configured otherwise in the application :file:`CMakeLists.txt`
- file.
+ CONFIG_SOME_BOOL=y
-#. Edit the file and add the appropriate configuration entries.
+ To ensure that a boolean configuration option is not set, add a line
+ like this instead (including the leading ``#`` symbol):
- a) Add each configuration entry on a new line.
+ .. code-block:: none
- b) Begin each entry with ``CONFIG_``.
+ # CONFIG_SOME_BOOL is not set
- c) Ensure that each entry contains no spaces
- (including on either side of the = sign).
+- You can set integer and string options as well, like this:
- d) Use a # followed by a space to comment a line.
+ .. code-block:: none
- The example below shows a comment line and a board
- configuration override in the :file:`prj.conf`.
+ CONFIG_SOME_INT=42
+ CONFIG_SOME_STRING="the best value ever"
- .. code-block:: c
+- Ensure that each entry setting an option contains no spaces
+ (including on either side of the = sign).
- # Enable printk for debugging
- CONFIG_PRINTK=y
+- Use a # followed by a space to comment a line:
-#. Save and close the file.
+ .. code-block:: none
+
+ # This is a comment.
+
+The example below shows a comment line and an override setting
+:option:`CONFIG_PRINTK` to ``y``:
+
+.. code-block:: c
+
+ # Enable printk for debugging
+ CONFIG_PRINTK=y
.. _override_kernel_conf:
