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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	…
sample.yaml	…

README.rst

.. _mcp9808-sample:

MCP9808 Temperature Sensor
##########################

Overview
********

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

If triggered measurements are enabled the sample initializes and
maintains a |plusminus| 2 |deg| C window around the current temperature.
When the temperature moves outside the window an alert is given, and the
window is moved to center on the new temperature.

Requirements
************

The MCP9808 digital temperature sensor converts temperatures between -20 |deg|
C and +100 |deg| C to a digital word with |plusminus| 0.5 |deg| C (max.)
accuracy. It is I2C compatible and supports up to 16 devices on the bus.

Wiring
*******

The MCP9808 is available in a discrete component form but it is much easier to
use it mounted on a breakout board.  We used the Adafruit `MCP9808
Sensor`_ breakout board.

.. _`MCP9808 Sensor`: https://www.adafruit.com/product/1782

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

After providing a devicetree overlay that specifies the sensor I2C bus
and alert GPIO, build this sample app using:

.. zephyr-app-commands::
   :zephyr-app: samples/sensor/mcp9808
   :board: particle_xenon
   :goals: build flash

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

Note that in the capture below output from the trigger callback and the
main thread are interleaved.

.. code-block:: console

   *** Booting Zephyr OS build zephyr-v2.1.0-537-gbbdeaa1ae5bb  ***
   Alert on temp outside [24500, 25500] milli-Celsius
   Trtrigger fired 1, temp 15.9375 C
   iggAlert on temp outside [15437, 16437] milli-Celsius
   er set got 0
   0:00:00.017: 15.9375 C
   0:00:02.020: 16 C
   0:00:04.022: 16.125 C
   0:00:06.024: 16.1875 C
   trigger fired 2, temp 16.3125 C
   Alert on temp outside [15812, 16812] milli-Celsius
   0:00:08.027: 16.3125 C
   0:00:10.029: 16.375 C
   0:00:12.032: 16.5 C
   0:00:14.034: 16.5625 C
   0:00:16.037: 16.5625 C
   0:00:18.039: 16.625 C
   0:00:20.042: 16.6875 C
   trigger fired 3, temp 16.8125 C
   Alert on temp outside [16312, 17312] milli-Celsius
   0:00:22.044: 16.8125 C
   0:00:24.047: 16.875 C