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

.. _ina219:

INA219 Bidirectional Power/Current Monitor
##########################################

Overview
********

This sample application measures shunt voltage, bus voltage, power and current
every 2 seconds and prints them to console.
The calibration/configuration parameters can be set in the devicetree file.

References
**********

 - `INA219 sensor <https://www.ti.com/product/INA219>`_

Wiring
******

The supply voltage of the INA219 can be in the 3V to 5.5V range.
The common mode voltage of the measured bus can be in the 0V to 26V range.

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

.. zephyr-app-commands::
   :zephyr-app: samples/sensor/ina219
   :board: blackpill_f411ce
   :goals: build flash

Sample Output
=============
When monitoring a 3.3 V bus with a 0.1 Ohm shunt resistor
you should get a similar output as below, repeated every 2 seconds:

.. code-block:: console

        Shunt: 0.001570 [V] -- Bus: 3.224000 [V] -- Power: 0.504000 [W] -- Current: 0.157000 [A]


A negative sign indicates current flowing in reverse direction:

.. code-block:: console

        Shunt: -0.001560 [V] -- Bus: 3.224000 [V] -- Power: 0.502000 [W] -- Current: -0.156000 [A]