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	…
CMakeLists.txt	…
README.rst	…
prj.conf	…
sample.yaml	…

README.rst

.. _mpr-sample:

MPR Pressure Sensor
###################

Overview
********

This sample application periodically (1Hz) measures atmospheric pressure in
kilopascal. The result is written to the console.

References
**********

- MPR: https://sensing.honeywell.com/micropressure-mpr-series

Wiring
******

This sample uses an MPRLS0025PA00001A sensor controlled using the i2c
interface. Connect **VIN**, **GND** and Interface: **SDA**, **SCL**.

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

This project outputs sensor data to the console. It requires a sensor from the
MPR series.
It does not work on QEMU.
In the sample below the :ref:`arduino_due` board is used.

.. zephyr-app-commands::
   :zephyr-app: samples/sensor/mpr
   :board: arduino_due
   :goals: build flash

Sample Output
*************

.. code-block:: console

   pressure value: 101.976303 kPa
   pressure value: 101.986024 kPa
   pressure value: 101.989736 kPa
   pressure value: 101.987424 kPa
   pressure value: 101.992099 kPa
   pressure value: 101.989171 kPa
   pressure value: 101.984226 kPa

   <repeats endlessly>