94 lines
2.4 KiB
ReStructuredText
94 lines
2.4 KiB
ReStructuredText
.. zephyr:code-sample:: lps22hh_i3c
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:name: LPSS22HH Temperature and Pressure Sensor (I3C)
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:relevant-api: sensor_interface
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Get pressure and temperature data from an LPS22HH sensor over I3C (polling &
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trigger mode).
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Overview
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********
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This sample periodically reads pressure from the LPS22HH MEMS pressure
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sensor and displays it on the console.
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Requirements
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************
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This sample uses the LPS22HH sensor controlled using the I3C interface.
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It has been tested using the LPS22HH on the evaluation board
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STEVALMKI192-V1 connected to the I3C header on :ref:`mimxrt685_evk`.
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References
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**********
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- LPS22HH: https://www.st.com/en/mems-and-sensors/lps22hh.html
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Building and Running
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********************
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This project outputs sensor data to the console. It requires an LPS22HH
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sensor (for example, the one on evaluation board STEVALMKI192-V1).
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.. note::
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If ``CONFIG_LPS22HH_TRIGGER`` is enabled, the trigger is using
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I3C In-Band Interrupt (IBI) to signal new data being available.
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Since IBI is initiated by the sensor, it will take over the I3C
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bus. Therefore, when flashing a new image, a power cycle is needed
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to reset the sensor so that it will not generate IBIs anymore.
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Or else the I3C controller will not be able to be initialized,
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resulting in the sample not being able to communicate with
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the sensor.
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Building on mimxrt685_evk board
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====================================
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.. zephyr-app-commands::
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:zephyr-app: samples/sensor/lps22hh_i3c
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:host-os: unix
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:board: mimxrt685_evk/mimxrt685s/cm33
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:goals: build
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:compact:
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Board Preparations
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==================
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mimxrt685_evk
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------------------
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On the board :ref:`mimxrt685_evk`, the I3C pins are exposed on the J18
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header, where:
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* SCL is on pin 1
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* SDA is on pin 2
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* Internal pull-up is on pin 3 (which is connected to pin 2 already)
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* Ground is on pin4
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LPS22HH
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^^^^^^^
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A LPS22HH sensor needs to be connected to this header. For example,
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the evaluation board STEVAL-MKI192V1 can be used. This needs to be
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prepared so that the LPS22HH sensor has address 0x5D (i.e. 0xBA,
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left-shifed).
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Sample Output
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=============
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.. code-block:: console
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Configured for triggered collection at 1 Hz
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Observation: 1
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Pressure: 97.474 kPa
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Temperature: 22.19 C
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Observation: 2
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Pressure: 97.466 kPa
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Temperature: 22.21 C
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Observation: 3
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Pressure: 97.473 kPa
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Temperature: 22.21 C
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Observation: 4
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Pressure: 97.455 kPa
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Temperature: 22.21 C
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<repeats endlessly every second>
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