Introduction: Arduino Temperature and Humidity Measuring System | Technic Joe

After building two useless games with Arduino and wasting my time by playing them I wanted to create something useful with Arduino. I came up with the idea of a temperature and airhumidity measuring system for plants. To make the project a bit more interesting I wanted the Arduino to automatically calculate the deviation to the optimal conditions of each plant.

Step 1: Building the Project on a Breadboard

Hardware is very simple. You need:

- an Arduino (Nano/Uno/...)

- a Nokia 5110 LCD Display

- a DHT22

- a Pushbutton

- 1 kΩ Resistor for the button

- 10 kΩ Resistor for the DHT22

Just build everything up like in the picture and the hardware is correctly connected. You can change to different digital pins of the Arduino, if you make adjustments in the program. There are different types of the Nokia LCD with different pinorders available. Maybe you'll have to adjust the wiring or change the program a bit.

Step 2: Prepare the Program

The program is very simple and easy to set up. The most important thing is to install the correct libraries ( Link to the three libraries: | | Just download the files and copy the libraries in the correct folder. You can change the pins for the Nokia 5110 LCD, the DHT22 and the button at the top of the program. If the displays contrast is not correct, you can adjust it too. For the program just download the .zip file and copy the folder.

Like in my last project I designed all the graphics with paint and used LCDAssistant to convert the pictures into hex.

Step 3: Shrinking the Project

To shrink the project I designed and milled a circuit board with Eagle. Finally I used a 3D-Printer to build a case for my measuring system. As always I designed the CAD-Files in Thinkercad and used the material PLA. I attached the circuit board layout, but I think it is easier to soldier everything on perfboard.