APA102 Sample Application¶
This sample application demonstrates basic usage of the APA102 LED strip driver, for controlling LED strips using APA102, Adafruit DotStar, and compatible driver chips.
- Ensure your Zephyr board, the 5V power supply, and the LED strip share a common ground.
- Connect the MOSI pin of your board’s SPI master to the data input pin of the first APA102 IC in the strip.
- Connect the SCLK pin of your board’s SPI master to the clock input pin of the first APA102 IC in the strip.
- Connect the 5V power supply pin to the 5V input of the LED strip.
Building and Running¶
The sample application is located at
in the Zephyr source tree.
Configure For Your Board¶
Now check if your board is already supported, by looking for a file
boards/YOUR_BOARD_NAME.conf in the application directory.
If your board isn’t supported yet, you’ll need to configure the application as follows.
Configure your board’s SPI master in a configuration file under
boards/in the sample directory.
To provide additional configuration for some particular board, create a
boards/YOUR_BOARD_NAME.conffile in the application directory. It will be merged into the application configuration.
In this file, you must ensure that the SPI peripheral you want to use for this demo is enabled. See
boards/nucleo_l432kc.conffor an example.
#. Configure your board’s dts overlay. See
nucleo_l432kc.overlayfor an example.
Set the number of LEDs in your strip in the application sources. This is determined by the macro
STRIP_NUM_LEDSin the file
Then build and flash the application:
# On Linux/macOS cd $ZEPHYR_BASE/samples/drivers/led_apa102 mkdir build && cd build # On Windows cd %ZEPHYR_BASE%\samples\drivers\led_apa102 mkdir build & cd build cmake -GNinja -DBOARD=<board> .. ninja flash
Refer to your board’s documentation for alternative
flash instructions if your board doesn’t support the
When you connect to your board’s serial console, you should see the following output:
***** BOOTING ZEPHYR OS zepyhr-v1.13.XX ***** [general] [INF] main: Found LED strip device APA102