zephyr/samples/drivers/led_pwm
Gerard Marull-Paretas 79e6b0e0f6 includes: prefer <zephyr/kernel.h> over <zephyr/zephyr.h>
As of today <zephyr/zephyr.h> is 100% equivalent to <zephyr/kernel.h>.
This patch proposes to then include <zephyr/kernel.h> instead of
<zephyr/zephyr.h> since it is more clear that you are including the
Kernel APIs and (probably) nothing else. <zephyr/zephyr.h> sounds like a
catch-all header that may be confusing. Most applications need to
include a bunch of other things to compile, e.g. driver headers or
subsystem headers like BT, logging, etc.

The idea of a catch-all header in Zephyr is probably not feasible
anyway. Reason is that Zephyr is not a library, like it could be for
example `libpython`. Zephyr provides many utilities nowadays: a kernel,
drivers, subsystems, etc and things will likely grow. A catch-all header
would be massive, difficult to keep up-to-date. It is also likely that
an application will only build a small subset. Note that subsystem-level
headers may use a catch-all approach to make things easier, though.

NOTE: This patch is **NOT** removing the header, just removing its usage
in-tree. I'd advocate for its deprecation (add a #warning on it), but I
understand many people will have concerns.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
2022-09-05 16:31:47 +02:00
..
boards
src includes: prefer <zephyr/kernel.h> over <zephyr/zephyr.h> 2022-09-05 16:31:47 +02:00
CMakeLists.txt
README.rst
prj.conf drivers: led: Remove unnecessary Kconfig settings 2022-08-11 17:46:43 +02:00
sample.yaml samples: drivers: led_pwm: Update driver to remove DEVICE_DT_GET 2022-07-23 11:39:11 -05:00

README.rst

.. _led_pwm:

LED PWM sample application
##########################

Overview
********

This sample allows to test the led-pwm driver. The first "pwm-leds" compatible
device instance found in DT is used. For each LEDs attached to this device
(child nodes) the same test pattern (described below) is executed. The LED API
functions are used to control the LEDs.

Test pattern
============

For each PWM LEDs (one after the other):

- Turning on
- Turning off
- Increasing brightness gradually
- Blinking on: 0.1 sec, off: 0.1 sec
- Blinking on: 1 sec, off: 1 sec
- Turning off

Building and Running
********************

This sample can be built and executed on all the boards with PWM LEDs connected.
The LEDs must be correctly described in the DTS: the compatible property of the
device node must match "pwm-leds". And for each LED, a child node must be
defined and the PWM configuration must be provided through a "pwms" phandle's
node.