zephyr

History

Keith Packard 0b90fd5adf samples, tests, boards: Switch main return type from void to int As both C and C++ standards require applications running under an OS to return 'int', adapt that for Zephyr to align with those standard. This also eliminates errors when building with clang when not using -ffreestanding, and reduces the need for compiler flags to silence warnings for both clang and gcc. Most of these changes were automated using coccinelle with the following script: @@ @@ - void + int main(...) { ... - return; + return 0; ... } Approximately 40 files had to be edited by hand as coccinelle was unable to fix them. Signed-off-by: Keith Packard <keithp@keithp.com>		2023-04-14 07:49:41 +09:00
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boards	…
src	samples, tests, boards: Switch main return type from void to int	2023-04-14 07:49:41 +09:00
CMakeLists.txt	…
README.rst	…
prj.conf	…
sample.yaml	…

README.rst

.. _dht:

DHT: Aosong DHT Digital-output Humidity and Temperature Sensor
##############################################################

Description
***********

This sample application periodically (0.5 Hz) measures the ambient
temperature and humidity. The result is written to the console.

Wiring
*******

This sample uses an external breakout for the sensor.  A devicetree
overlay must be provided to identify the sensor variant and the GPIO
used to control the sensor.

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

After providing a devicetree overlay that specifies the sensor location,
build this sample app using:

.. zephyr-app-commands::
   :zephyr-app: samples/sensor/dht
   :board: nrf52dk_nrf52832
   :goals: build flash

Sample Output
=============

.. code-block:: console

   *** Booting Zephyr OS build zephyr-v2.1.0-329-g38418b26c4cc  ***
   [0:00:00.027]: 20.0 Cel ; 48.7 %RH
   [0:00:02.053]: 19.8 Cel ; 48.7 %RH
   [0:00:04.079]: 20.0 Cel ; 48.7 %RH
   [0:00:06.105]: 19.8 Cel ; 48.7 %RH
   [0:00:08.130]: 20.0 Cel ; 48.8 %RH
   [0:00:10.156]: 20.1 Cel ; 48.8 %RH
   [0:00:12.182]: 19.7 Cel ; 48.7 %RH
   [0:00:14.207]: 20.0 Cel ; 48.8 %RH

<repeats endlessly>