# Adafruit HTU21D-F Temperature & Humidity Sensor

## Overview

![](https://cdn-learn.adafruit.com/assets/assets/000/101/434/medium800/temperature___humidity_HTU_top.jpg?1618430995)

It's summer and you're sweating and your hair's all frizzy and all you really want to know is why the weatherman said this morning that today's relative humidity would max out at a perfectly reasonable 52% when it feels more like 77%. Enter the **HTU21D-F Temperature + Humidity Sensor** - the best way to prove the weatherman wrong!

![](https://cdn-learn.adafruit.com/assets/assets/000/101/435/medium800/temperature___humidity_HTU_back.jpg?1618431002)

This I2C digital humidity sensor is an accurate and intelligent alternative to the much simpler [Humidity and Temperature Sensor - SHT15 Breakout](https://www.adafruit.com/products/1638) It has a typical accuracy of ±2% with an operating range that's optimized from 5% to 95% RH. Operation outside this range is still possible - just the accuracy might drop a bit. The temperature output has an accuracy of ±1°C from -30~90°C. If you're looking to measure temperature more accurately, we recommend the [MCP9808 High Accuracy I2C Temperature Sensor Breakout Board.](https://www.adafruit.com/products/1782)

![](https://cdn-learn.adafruit.com/assets/assets/000/101/437/medium800/temperature___humidity_HTU_top_angle.jpg?1618431111)

Such a lovely chip - so we spun up a breakout board that includes the Filtered version (the white bit of plastic which is a PTFE filter to keep the sensor clean), a 3.3V regulator and I2C level shifting circuitry. This lets you use it safely with any kind of microcontroller with 3.3V-5V power or logic.

![](https://cdn-learn.adafruit.com/assets/assets/000/101/436/medium800/temperature___humidity_HTU_top_header.jpg?1618431094)

To get you going fast, we spun up a custom made PCB in the[**STEMMA QT** form factor](https://www.adafruit.com/?q=stemma%20qt%20sensor "STEMMA QT form factor"), making them easy to interface with. The [STEMMA QT connectors](https://learn.adafruit.com/introducing-adafruit-stemma-qt/what-is-stemma-qt) on either side are compatible with the [SparkFun Qwiic](https://www.sparkfun.com/qwiic) I2C connectors. This allows you to make solderless connections between your development board and the HTU21Ds or to chain them with a wide range of other sensors and accessories using a [**compatible cable**](https://www.adafruit.com/?q=stemma%20qt%20cable). [QT Cable is not included, but we have a variety in the shop](https://www.adafruit.com/?q=stemma+qt+cable&sort=BestMatch).

Each order comes with one fully assembled and tested PCB breakout and a small piece of header. You'll need to solder the header onto the PCB but it's fairly easy and takes only a few minutes even for a beginner.

Info: 

![](https://cdn-learn.adafruit.com/assets/assets/000/017/113/medium800/sensors_1899-01.jpg?1401846030)

# Adafruit HTU21D-F Temperature & Humidity Sensor

## Pinouts

The HTU21D-F is a I2C sensor. That means it uses the two I2C data/clock wires available on most microcontrollers, and can share those pins with other sensors as long as they don't have an address collision. For future reference, the I2C address is **0x40** and you _can't_ change it!

![](https://cdn-learn.adafruit.com/assets/assets/000/101/438/medium800/temperature___humidity_HTU_pinouts.jpg?1618431437)

![](https://cdn-learn.adafruit.com/assets/assets/000/017/115/medium800/sensors_pinouts.png?1401846159)

## Power Pins:

- **Vin** - this is the power pin. Since the chip uses 3 VDC, we have included a voltage regulator on board that will take 3-5VDC and safely convert it down. To power the board, give it the same power as the logic level of your microcontroller - e.g. for a 5V micro like Arduino, use 5V
- **3Vo (3v3 on original version)** - this is the 3.3V output from the voltage regulator, you can grab up to 100mA from this if you like
- **GND** - common ground for power and logic

## I2C Logic pins:

- **SCL** - I2C clock pin, connect to your microcontrollers I2C clock line.
- **SDA** - I2C data pin, connect to your microcontrollers I2C data line.
- **[STEMMA QT](https://learn.adafruit.com/introducing-adafruit-stemma-qt) -** These connectors allow you to connect to development boards with **STEMMA QT** connectors, or to other things, with [various associated accessories](https://www.adafruit.com/?q=JST%20SH%204).

# Adafruit HTU21D-F Temperature & Humidity Sensor

## Assembly

![](https://cdn-learn.adafruit.com/assets/assets/000/017/128/medium800/sensors_1899-01.jpg?1401898656)

 
## Prepare the header strip:
Cut the strip to length if necessary. It will be easier to solder if you insert it into a breadboard - **long pins down** ![sensors_header.jpg](https://cdn-learn.adafruit.com/assets/assets/000/017/129/medium640/sensors_header.jpg?1401898667)

## Add the breakout board:
Place the breakout board over the pins so that the short pins poke through the breakout pads![sensors_place.jpg](https://cdn-learn.adafruit.com/assets/assets/000/017/134/medium640/sensors_place.jpg?1401898834)

 
## And Solder!
 Be sure to solder all pins for reliable electrical contact.  
  
_(For tips on soldering, be sure to check out our_ [_Guide to Excellent Soldering_](http://learn.adafruit.com/adafruit-guide-excellent-soldering)_)._![sensors_solder1.jpg](https://cdn-learn.adafruit.com/assets/assets/000/017/131/medium640/sensors_solder1.jpg?1401898721)

![sensors_solder2.jpg](https://cdn-learn.adafruit.com/assets/assets/000/017/132/medium640/sensors_solder2.jpg?1401898750)

You're done! Check your solder joints visually and continue onto the next steps

![sensors_done.jpg](https://cdn-learn.adafruit.com/assets/assets/000/017/135/medium640/sensors_done.jpg?1401898844)

# Adafruit HTU21D-F Temperature & Humidity Sensor

## Wiring & Test

You can easily wire this breakout to any microcontroller, we'll be using an Arduino. For another kind of microcontroller, just make sure it has I2C, then port the code - its pretty simple stuff!

- Connect **Vin** to the power supply, 3-5V is fine. **(red wire on STEMMA QT version)** Use the same voltage that the microcontroller logic is based off of. For most Arduinos, that is 5V
- Connect **GND** to common power/data ground **(black wire on STEMMA QT version)**
- Connect the **SCL** pin to the I2C clock **SCL** pin on your Arduino. **(yellow wire on STEMMA QT version)** On an UNO & '328 based Arduino, this is also known as **A5** , on a Mega it is also known as **digital 21** and on a Leonardo/Micro, **digital 3**
- Connect the **SDA** pin to the I2C data **SDA** pin on your Arduino. **(blue wire on STEMMA QT verison)** On an UNO & '328 based Arduino, this is also known as **A4** , on a Mega it is also known as **digital 20** and on a Leonardo/Micro, **digital 2**

The HTU21D-F has a default I2C address of **0x40** and cannot be changed!

![temperature___humidity_HTU_arduino_STEMMA_bb.jpg](https://cdn-learn.adafruit.com/assets/assets/000/101/444/medium640/temperature___humidity_HTU_arduino_STEMMA_bb.jpg?1618434738)

![temperature___humidity_HTU_arduino_breadboard_bb.jpg](https://cdn-learn.adafruit.com/assets/assets/000/101/445/medium640/temperature___humidity_HTU_arduino_breadboard_bb.jpg?1618434754)

![temperature___humidity_HTU_arduino_original.jpg](https://cdn-learn.adafruit.com/assets/assets/000/101/446/medium640/temperature___humidity_HTU_arduino_original.jpg?1618434773)

# Download Adafruit\_HTU21DF

To begin reading sensor data, you will need to download the  **Adafruit HTU21DF ** library from the Arduino library manager.

Open up the Arduino library manager:

![](https://cdn-learn.adafruit.com/assets/assets/000/084/399/medium800/temperature___humidity_1library_manager_menu.png?1573954893)

Search for the  **Adafruit HTU21DF ** library and install it

![](https://cdn-learn.adafruit.com/assets/assets/000/084/398/medium800/temperature___humidity_htu21df.png?1573954851)

We also have a great tutorial on Arduino library installation at:  
[http://learn.adafruit.com/adafruit-all-about-arduino-libraries-install-use](http://learn.adafruit.com/adafruit-all-about-arduino-libraries-install-use "Link: http://learn.adafruit.com/adafruit-all-about-arduino-libraries-install-use")

# Load Demo
Open up **File-\>Examples-\>Adafruit\_HTU21DF**** -\>HTU21DFtest** and upload to your Arduino wired up to the sensor ![](https://cdn-learn.adafruit.com/assets/assets/000/017/117/medium800/sensors_loadup.png?1401848116)

Thats it! Now open up the serial terminal window at 9600 speed to begin the test.

![](https://cdn-learn.adafruit.com/assets/assets/000/017/119/medium800/sensors_test.png?1401848456)

You can try breathing on the sensor to increase the humidity. The sensor reacts very fast!

# Library Reference
The library we have is simple and easy to use  
  
You can create the **Adafruit\_HTU21DF** object with:

```
Adafruit_HTU21DF htu = Adafruit_HTU21DF()
```

There are no pins to set since you must use the I2C bus!  
  
Then initialize the sensor with:

```
htu.begin()
```

this function returns **True** if the sensor was found and responded correctly and **False** if it was not found  
  
Once initialized, you can query the temperature in °C with

```
htu.readTemperature()
```

Which will return floating point (decimal + fractional) temperature. You can convert to Fahrenheit by multiplying by 1.8 and adding 32 as you have learned in grade school!  
  
Reading the humidity is equally simple. Call

```
htu.readHumidity()
```

to read the humidity also as a floating point value between 0 and 100 (this reads % humidity)

# Adafruit HTU21D-F Temperature & Humidity Sensor

## Python & CircuitPython

It's easy to use the HTU21D-F sensor with Python or CircuitPython and the [Adafruit CircuitPython HTU21D](https://github.com/adafruit/Adafruit_CircuitPython_HTU21D) module.  This module allows you to easily write Python code that reads the humidity and temperature from the sensor.

You can use this sensor with any CircuitPython microcontroller board or with a computer that has GPIO and Python [thanks to Adafruit\_Blinka, our CircuitPython-for-Python compatibility library](https://learn.adafruit.com/circuitpython-on-raspberrypi-linux).

# CircuitPython MicroController Wiring
First wire up a HTU21D-F to your board exactly as shown on the previous pages for Arduino. Here's an example of wiring a Feather M0 Express to the sensor with I2C:

- **Board 3V3** to **sensor VIN (red wire on STEMMA QT version)**  
- **Board GND** to **sensor GND (black wire on STEMMA QT version)**  
- **Board SCL** to **sensor SCL (yellow wire on STEMMA QT version)**  
- **Board SDA** to **sensor SDA (blue wire on STEMMA QT version)**

![temperature___humidity_feather_m0_express_htu21d-f_i2c_bb_rot.png](https://cdn-learn.adafruit.com/assets/assets/000/062/683/medium640/temperature___humidity_feather_m0_express_htu21d-f_i2c_bb_rot.png?1538158123)

![temperature___humidity_HTU_Feather_STEMMA_bb.jpg](https://cdn-learn.adafruit.com/assets/assets/000/101/447/medium640/temperature___humidity_HTU_Feather_STEMMA_bb.jpg?1618434878)

![temperature___humidity_HTU_Feather_breadboard_bb.jpg](https://cdn-learn.adafruit.com/assets/assets/000/101/448/medium640/temperature___humidity_HTU_Feather_breadboard_bb.jpg?1618434892)

# Python Computer Wiring
Since there's _dozens_ of Linux computers/boards you can use we will show wiring for Raspberry Pi. For other platforms, [please visit the guide for CircuitPython on Linux to see whether your platform is supported](https://learn.adafruit.com/circuitpython-on-raspberrypi-linux). 

Here's the Raspberry Pi wired with I2C:

- **Pi GND** to **sensor GND (black wire on STEMMA QT version)**  
- **Pi 3V3** to **sensor VIN (red wire on STEMMA QT version)**  
- **Pi SDA** to **sensor SDA (blue wire on STEMMA QT version)**  
- **Pi SCL** to **sensor SCL (yellow wire on STEMMA QT version)**

![temperature___humidity_raspi_htu21d-f_i2c_bb.png](https://cdn-learn.adafruit.com/assets/assets/000/062/682/medium640/temperature___humidity_raspi_htu21d-f_i2c_bb.png?1538158004)

![temperature___humidity_HTU_RasPi_STEMMA_bb.jpg](https://cdn-learn.adafruit.com/assets/assets/000/101/449/medium640/temperature___humidity_HTU_RasPi_STEMMA_bb.jpg?1618434957)

![temperature___humidity_HTU_RasPi_breadboard_bb.jpg](https://cdn-learn.adafruit.com/assets/assets/000/101/450/medium640/temperature___humidity_HTU_RasPi_breadboard_bb.jpg?1618434982)

# CircuitPython Installation of HTU21D Library
You'll need to install the [Adafruit CircuitPython HTU21D](https://github.com/adafruit/Adafruit_CircuitPython_HTU21D) library on your CircuitPython board.

First make sure you are running the [latest version of Adafruit CircuitPython](https://learn.adafruit.com/welcome-to-circuitpython/installing-circuitpython) for your board.

Next you'll need to install the necessary libraries to use the hardware--carefully follow the steps to find and install these libraries from [Adafruit's CircuitPython library bundle](https://github.com/adafruit/Adafruit_CircuitPython_Bundle/releases).  Our CircuitPython starter guide has [a great page on how to install the library bundle](https://learn.adafruit.com/welcome-to-circuitpython/circuitpython-libraries).

For non-express boards like the Trinket M0 or Gemma M0, you'll need to manually install the necessary libraries from the bundle:

- **adafruit\_htu21d.mpy**
- **adafruit\_bus\_device**

Before continuing make sure your board's lib folder or root filesystem has the **adafruit\_htu21d.mpy,** and **adafruit\_bus\_device****   **files and folders**  **copied over.

Next[ connect to the board's serial REPL](https://learn.adafruit.com/welcome-to-circuitpython/the-repl) so you are at the CircuitPython  **\>\>\>**  prompt.

# Python Installation of HTU21D Library
You'll need to install the Adafruit\_Blinka library that provides the CircuitPython support in Python. This may also require enabling I2C on your platform and verifying you are running Python 3. [Since each platform is a little different, and Linux changes often, please visit the CircuitPython on Linux guide to get your computer ready](https://learn.adafruit.com/circuitpython-on-raspberrypi-linux)!

Once that's done, from your command line run the following command:

- `sudo pip3 install adafruit-circuitpython-htu21d`

If your default Python is version 3 you may need to run 'pip' instead. Just make sure you aren't trying to use CircuitPython on Python 2.x, it isn't supported!

# CircuitPython & Python Usage
To demonstrate the usage of the sensor we'll initialize it and read the humidity and temperature values from the board's Python REPL.

Run the following code to import the necessary modules and initialize the I2C connection with the sensor:

```
    import time
import board
import busio
from adafruit_htu21d import HTU21D

# Create library object using our Bus I2C port
i2c = busio.I2C(board.SCL, board.SDA)
sensor = HTU21D(i2c)
  
```

Now you're ready to read values from the sensor using any of these properties:

- **temperature** - the temperature in degrees Celsius.
- **relative\_humidity** - the relative humidity in percent.

For example to print temperature:

```
    print("\nTemperature: %0.1f C" % sensor.temperature)
  
```

![](https://cdn-learn.adafruit.com/assets/assets/000/062/671/medium800/temperature___humidity_Screenshot-2018-09-28-11_01_56.png?1538154150)

That's all there is to using the HTU21D-F sensor with CircuitPython!

# Full Example Code
https://github.com/adafruit/Adafruit_CircuitPython_HTU21D/blob/main/examples/htu21d_simpletest.py

# Adafruit HTU21D-F Temperature & Humidity Sensor

## Python Docs

# Adafruit HTU21D-F Temperature & Humidity Sensor

## WipperSnapper

![](https://cdn-learn.adafruit.com/assets/assets/000/125/163/medium800/temperature___humidity_01_DeviceList.png?1697218957)

## What is WipperSnapper

WipperSnapper is a firmware designed to turn any WiFi-capable board into an Internet-of-Things device without programming a single line of code. WipperSnapper connects to [Adafruit IO](https://io.adafruit.com/), a web platform designed ([by Adafruit!](https://www.adafruit.com/about)) to _display_, _respond_, and _interact_ with your project's data.

Simply load the WipperSnapper firmware onto your board, add credentials, and plug it into power. Your board will automatically register itself with your Adafruit IO account.

From there, you can add _components_ to your board such as buttons, switches, potentiometers, sensors, and more! Components are _dynamically _added to hardware, so you can immediately start interacting, logging, and streaming the data your projects produce without writing code.

If you've never used WipperSnapper, click below to read through the quick start guide before continuing.

[Quickstart: Adafruit IO WipperSnapper](https://learn.adafruit.com/quickstart-adafruit-io-wippersnapper)
## Wiring
First, wire up an HTU21-D to your board exactly as follows. Here is an example of the HTU21-D wired to an [Adafruit ESP32 Feather V2](https://www.adafruit.com/product/5400) using I2C [with a STEMMA QT cable (no soldering required)](https://www.adafruit.com/product/4210)

 

- **Board 3V**  to **sensor VIN (red wire on STEMMA QT)**  
- **Board GND**  to **sensor GND (black wire on STEMMA QT)**  
- **Board SCL**  to **sensor SCL (yellow wire on STEMMA QT)**  
- **Board SDA**  to **sensor SDA (blue wire on STEMMA QT)**

![temperature___humidity_featherV2_HTU21-D_Breadboard_bb.png](https://cdn-learn.adafruit.com/assets/assets/000/125/165/medium640/temperature___humidity_featherV2_HTU21-D_Breadboard_bb.png?1697219948)

![temperature___humidity_featherV2_HTU21-D_bb.png](https://cdn-learn.adafruit.com/assets/assets/000/125/166/medium640/temperature___humidity_featherV2_HTU21-D_bb.png?1697220006)

## Usage

Connect your board to Adafruit IO Wippersnapper and **[navigate to the WipperSnapper board list](https://io.adafruit.com/wippersnapper).**

On this page, **select the WipperSnapper board you're using** to be brought to the board's interface page.

![](https://cdn-learn.adafruit.com/assets/assets/000/125/167/medium800/temperature___humidity_02_DeviceSelection.png?1697220106)

If you do not see your board listed here - you need [to connect your board to Adafruit IO](https://learn.adafruit.com/quickstart-adafruit-io-wippersnapper) first.

On the device page, quickly  **check that you're running the latest version of the WipperSnapper firmware**.

The device tile on the left indicates the version number of the firmware running on the connected board.

- **If the firmware version is green with a checkmark -**  continue with this guide.
- **If the firmware version is red with an exclamation mark "!" -**  [update to the latest WipperSnapper firmware](https://learn.adafruit.com/quickstart-adafruit-io-wippersnapper) on your board before continuing.

![temperature___humidity_04_LatestVersion.png](https://cdn-learn.adafruit.com/assets/assets/000/125/301/medium640/temperature___humidity_04_LatestVersion.png?1697553285)

![temperature___humidity_04_UpdateRequired.png](https://cdn-learn.adafruit.com/assets/assets/000/125/302/medium640/temperature___humidity_04_UpdateRequired.png?1697553304)

Next, make sure the sensor is plugged into your board and click the ** I2C Scan ** button.

![](https://cdn-learn.adafruit.com/assets/assets/000/113/177/medium800/sensor_page_crop_scan.png?1657724520)

You should see the HTU21-D's default I2C address of `0x40` pop-up in the I2C scan list.

![](https://cdn-learn.adafruit.com/assets/assets/000/125/303/medium800/temperature___humidity_I2C_0x40.png?1697553561)

###  I don't see the sensor's I2C address listed! 


First, double-check the connection and/or wiring between the sensor and the board.

Then, reset the board and let it re-connect to Adafruit IO WipperSnapper.

With the sensor detected in an I2C scan, you're ready to add the sensor to your board.

**Click the New Component button or the + button** to bring up the component picker.

![](https://cdn-learn.adafruit.com/assets/assets/000/127/931/medium800/sensor_page_temperature___humidity_06_AddComponent.png?1708631009)

Adafruit IO supports a large amount of components. To quickly find your sensor, type `HTU12-D` into the search bar, then select the  **HTU21-D** from the component picker.

![](https://cdn-learn.adafruit.com/assets/assets/000/126/880/medium800/temperature___humidity_HTU21D_twin_arrows_text.png?1704473227)

On the component configuration page, the HTU21-D's sensor address should be listed along with the sensor's settings.

The  **Send Every**  option is specific to each sensor's measurements. This option will tell the Feather how often it should read from the HTU21-D sensor and send the data to Adafruit IO. Measurements can range from every 30 seconds to every 24 hours.

For this example, set the  **Send Every ** interval to every 30 seconds.

![](https://cdn-learn.adafruit.com/assets/assets/000/125/309/medium800/temperature___humidity_Screenshot_2023-10-17_160434.png?1697555091)

Your device interface should now show the sensor components you created. After the interval you configured elapses, WipperSnapper will automatically read values from the sensor(s) and send them to Adafruit IO.

![](https://cdn-learn.adafruit.com/assets/assets/000/125/310/medium800/temperature___humidity_Screenshot_2023-10-17_160208.png?1697555109)

To view the data that has been logged from the sensor, click on the graph next to the sensor name.

![](https://cdn-learn.adafruit.com/assets/assets/000/125/311/medium800/temperature___humidity_chDhGeeWor.png?1697555121)

Here you can see the feed history and edit things about the feed such as the name, privacy, webhooks associated with the feed and more. If you want to learn more about how feeds work, [check out this page](https://learn.adafruit.com/all-the-internet-of-things-episode-four-adafruit-io/advanced-feeds).

![](https://cdn-learn.adafruit.com/assets/assets/000/125/312/medium800/temperature___humidity_ywIGRkiGJM.png?1697555132)

# Adafruit HTU21D-F Temperature & Humidity Sensor

## Downloads

# Files & Datasheets

- [Datasheet for the HTU21D-F](http://www.adafruit.com/datasheets/1899_HTU21D.pdf) (the -F part is for the PTFE **F** ilter, which is the white insert on top of the sensor)
- [Fritzing object in Adafruit Fritzing library](https://github.com/adafruit/Fritzing-Library)
- [EagleCAD PCB files in GitHub](https://github.com/adafruit/Adafruit-HTU21D-Breakout-PCB)
- [K&R Smith calibration notes](http://www.kandrsmith.org/RJS/Misc/Hygrometers/calib_many.html)

# Schematic and Fab Print for STEMMA QT Version
![](https://cdn-learn.adafruit.com/assets/assets/000/101/441/medium800/temperature___humidity_HTU_sch.png?1618433334)

![](https://cdn-learn.adafruit.com/assets/assets/000/101/442/medium800/temperature___humidity_HTU_fab_print.png?1618433342)

# Schematic and Fab Print for Original Version
![](https://cdn-learn.adafruit.com/assets/assets/000/017/120/medium800/sensors_schem.png?1401849523)

![](https://cdn-learn.adafruit.com/assets/assets/000/017/121/medium800/sensors_print.png?1401849552)


## Primary Products

### Adafruit HTU21D-F Temperature & Humidity Sensor Breakout Board

[Adafruit HTU21D-F Temperature & Humidity Sensor Breakout Board](https://www.adafruit.com/product/1899)
It's summer and you're sweating and your hair's all frizzy and all you really want to know is why the weatherman said this morning that today's relative humidity would max out at a perfectly reasonable 52% when it feels more like 77%. Enter the **HTU21D-F Temperature +...**

In Stock
[Buy Now](https://www.adafruit.com/product/1899)
[Related Guides to the Product](https://learn.adafruit.com/products/1899/guides)
### Adafruit HTU21D-F Temperature & Humidity Sensor Breakout Board

[Adafruit HTU21D-F Temperature & Humidity Sensor Breakout Board](https://www.adafruit.com/product/3515)
It's summer and you're sweating and your hair's all frizzy and all you really want to know is why the weatherman said this morning that today's relative humidity would max out at a perfectly reasonable 52% when it feels more like 77%. Enter the **HTU21D-F Temperature +...**

No Longer Stocked
[Buy Now](https://www.adafruit.com/product/3515)
[Related Guides to the Product](https://learn.adafruit.com/products/3515/guides)

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- [CircuitPython BLE Multi-Temperature Monitoring](https://learn.adafruit.com/circuitpython-multi-temperature-ble-monitoring.md)
- [NeoPixel Sprite Weather Display](https://learn.adafruit.com/neopixel-sprite-weather-display.md)
- [Raspberry Pi Azure IoT Hub Dashboard with CircuitPython](https://learn.adafruit.com/raspberry-pi-iot-dashboard-with-azure-and-circuitpython.md)