DIY Arduino Uno Mini LE Weather Station

By: Pranav Putta

With this project, you'll find the fundamental instructions for building a circuit board that will eventually show the ambient humidity and temperature on an LCD screen. For those who have worked with Arduino before, this is a great project using the Arduino Mini LE microcontroller board. It is encouraged that you make this kit your own by modifying the project to your liking and expanding upon the instructions.

To get started, it helps to have a fundamental understanding of the components that make up a breadboard and an Arduino Uno Mini. Take a look at the following diagrams:

Arduino Uno Mini Limited-Edition Layout

Arduino Uno Mini Layout


Breadboard Layout

Breadboard Layout


Digital Temperature Humidity Sensor Module Layout (DHT 11)

Note: Double check the pins on your DHT 11 sensor, as some have different layouts than the image below.

Sensor


Serial I2C TWI Module

Serial I2C TWI Module

16x2 LCD Display

LCD Display


The parts you need to get started:

STEP 1 Attach the 16 x 2 LCD to the breadboard using the pins on the backside as shown below.

LCD Display and Breadboard


Step 2: Attach the Digital Temperature Humidity Sensor Module as shown below. Refer to the DHT 11 layout above for what each pin is labeled as (Double check online as some DHT 11 sensors have different pin layouts). Attach a male-to-male jumper wire from the VCC node to the negative (-) rail of the breadboard. Attach a male-to-male jumper wire from the Data node to the A0 port on the Arduino Uno Mini Limited Edition. Attach a male-to-male jumper write from the GND node to the positive (+) rail of the breadboard. Refer to the images below for clarity:

Note: You can find the ports on the Arduino Mini Limited Edition labeled underneath it.

Breadboard Sensor

Arduino Mini


Step 3: Attach the I2C TWI Module above the pre-soldered pins of the LCD. Attach 4 male to female jumper wires to the I2C TWI Module. Refer to the images below.

I2C Attach

Step 4: Wire the GND port on the I2C TWI Module to the negative (-) rail on the breadboard, the VCC port to the positive (+) rail, the SDA port to the SDA port on the Arduino Uno Mini Limited Edition, and the SCL port to the SCL port on the Arduino Uno Mini Limited Edition. Refer to the images below:

Ground Port Wire


Arduino Wired


Step 5: Connect the 5V port on the Arduino Uno Mini Limited Edition to the positive (+) rail on the breadboard. Connect the GND port on the Arduino Uno Mini Limited Edition to the negative (-) rail on the breadboard. Refer to the images below:
5V Port


Project Connected


Step 6: Connect the Arduino Uno Mini to your laptop/computer. Open the Arduino IDE and use the code which is linked in the article below (Use the article as a guide to this project as well). You will need to download the libraries linked below as well. After you’ve completed these steps, you may upload the code to your Arduino.

Libraries Link
Code Link

Weather Station Demonstration Photo

Note: You may need to use a screwdriver to twist the blue square on the I2C module to change the contrast of the LCD if it displays a blank screen.

Completed Weather Station