Note

This is the documentation for the latest development branch and may refer to features that are not available in released versions. If you are looking for the documentation for a specific release, use the drop-down menu on the left and select the desired version.

How to Run and Add a HelloWorld Application

This document covers two parts:

• First, run the HelloWorld already provided by the SDK (quickest way to verify your environment)

• Then, add or modify your own HelloWorld application

Run the Built-in HelloWorld (Recommended First)

The SDK provides a sample directory: src/applications/helloworld

cd <sdk_root>
ls src/applications/helloworld

If the directory contains Kconfig, Makefile, and main.c, the sample is ready to use.

Enable the HelloWorld Build Switch

make menuconfig

Enable the following option in the menu:

Application Configuration > Enable Application HelloWorld

Build and Flash

make

After flashing, the application will be packaged into the /sdcard/app/ directory on the board.

Run on the Board

/sdcard/app/helloworld

Add / Modify HelloWorld

You can modify the existing src/applications/helloworld directly, or copy it as a new application directory.

Build

Build Standalone

cd <sdk_root>/src/applications/helloworld
make
ls

This produces an executable helloworld that you can manually copy to the board and run.

Build as Part of the Full Image

1. Edit src/applications/apps.mk to add the corresponding directory to the build system.

cat src/applications/apps.mk
-include $(SDK_SRC_ROOT_DIR)/.config

subdirs-$(CONFIG_APP_ENABLE_HELLOWORLD) += helloworld

1. Enable the APP build feature in menuconfig.

make menuconfig

Application Configuration > Enable Application HelloWorld

Then run make or make app to build the applications under src/applications.

make

Flash the resulting image to the development board. The application will be packaged into the image’s /sdcard/app/ directory, where it can be set to auto-start on boot or run manually for testing.