zephyr/samples/sensor/mpr
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
..
boards samples: sensors: Remove label property from devicetree overlays 2022-07-19 08:23:35 -05:00
src samples, tests, boards: Switch main return type from void to int 2023-04-14 07:49:41 +09:00
CMakeLists.txt cmake: use find_package() instead of literal include in tests and samples 2021-11-01 10:33:09 -04:00
prj.conf sensors: Remove unnecessary Kconfig setting of sensors 2022-07-25 15:18:56 +02:00
README.rst sample: sensor: mpr: Add MPR sample application 2020-04-22 17:39:31 +02:00
sample.yaml tests/samples: fix usage of integration_platforms 2022-05-14 14:49:59 -04:00

.. _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>