| .. _thermometer-sample: |
| |
| Thermometer sample |
| ################## |
| |
| Overview |
| ******** |
| |
| This sample application periodically measures the ambient temperature |
| at 1Hz. The result is written to the console. |
| |
| Wiring |
| ******* |
| |
| VDD pin should be connected to 2.3V to 5.5V |
| GND pin connected to 0V |
| VOUT pin connected to the ADC input pin. |
| |
| .. _`MCP970X Sensor`: http://ww1.microchip.com/downloads/en/devicedoc/20001942g.pdf |
| |
| An overlay is provided for the nrf52840dk_nrf52840 board with the |
| sensor connected to pin AIN7. |
| |
| Building and Running |
| ******************** |
| |
| To build for the nrf52840dk_nrf52840 board use: |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/sensor/thermometer |
| :board: nrf52840dk_nrf52840 |
| :goals: build flash |
| :compact: |
| |
| |
| To build for other boards and ambient temperature sensors, enable the sensor |
| node that supports ``SENSOR_CHAN_AMBIENT_TEMP`` and use an overlay to create an |
| alias named ``ambient-temp0`` to link to the node. See the overlay used for the |
| ``nrf52840dk_nrf52840`` board within this sample: |
| ``boards/nrf52840dk_nrf52840.overlay`` |
| |
| |
| Temperature Alert |
| ================= |
| |
| If the attached sensor supports alerts when the temperature drifts above or |
| below a threshold, the sample will enable the sensor's trigger functionality. |
| This will require the sensor's TRIGGER KConfig setting to be enabled. An |
| example of this setup is provided for the ``frdm_k22f`` board, using |
| ``boards/frdm_k22f.conf``. |
| |
| Sample Output |
| ============= |
| |
| .. code-block:: console |
| |
| *** Booting Zephyr OS build zephyr-v3.3.0-2354-gb4f4bd1f1c22 *** |
| Thermometer Example (arm) |
| Temperature device is 0x525c, name is tcn75a@48 |
| Set temperature lower limit to 25.5°C |
| Set temperature upper limit to 26.5°C |
| Enabled sensor threshold triggers |
| Temperature is 25.0°C |
| Temperature is 25.0°C |
| Temperature is 25.0°C |
| Temperature is 25.0°C |
| Temperature is 25.5°C |
| Temperature above threshold: 26.5°C |
| Temperature is 26.5°C |