DHT Temperature and Humidity Readings Displayed on the on- board ESP8266's OLED Display
426.DHT Temperature and Humidity Readings Displayed on the on- board ESP8266's OLED Display Discover how to read the temperature and humidity from a DHT11 or DHT22 sensor on an SSD1306 OL…
Know the mission before touching a wire.
Understand what you are making, prepare the right tools, and make the workbench safe.
Project details
DHT Temperature and Humidity Readings Displayed on the on- board ESP8266's OLED Display is a iot project. 426.DHT Temperature and Humidity Readings Displayed on the on- board ESP8266's OLED Display Discover how to read the temperature and humidity from a DHT11 or DHT22 sensor on an SSD1306 OL…
- Source pages
- 1022-1027
- Named parts
- 6
- Build goal
- Working, tested prototype
Tools you need
- Digital multimeter
- Wire stripper and side cutters
- Soldering iron with a fine tip
- Current-limited bench supply
- Computer with a data-capable USB cable
Use eye protection, good lighting, and a clean insulated surface throughout the build.
Safety precautions
- Disconnect every power source before changing a connection.
- Check component polarity, pinout, and supply voltage twice.
- Use a current limit for the first power-up.
- Keep liquids, loose metal, and uninsulated wires away from the bench.
Gather, identify, and understand every part.
Use the standardized inventory, then open What's this? to learn each part's role, advantages, limitations, handling, and specifications.
What's this?Image, role, pros, cons, handling & specifications
inches of OLED screen real estate
An output component turns an electrical control signal into light, sound, motion, switching, or displayed information.
What it does hereIt presents the circuit result or acts on the physical world.
Buy / compare this part ↗Advantages
- Makes system state visible
- Can be tested separately
- Supports clear troubleshooting
Limitations
- Loads may exceed controller current
- Polarity or driver direction can matter
- Inductive loads create voltage spikes
Handling
- Use the documented driver stage
- Check polarity and load current
- Add flyback protection for inductive loads
Specifications to verify
- Use the exact model, value, package, and rating listed for inches of OLED screen real estate; similar-looking parts are not always interchangeable.
- Confirm voltage, current, polarity, interface, driver requirements, and duty cycle.
What's this?Image, role, pros, cons, handling & specifications
ESP32 or ESP8266; both are available (read ESP32 vs ESP8266)
A programmable controller that reads inputs, makes decisions, and drives the project's outputs.
What it does hereIt is the control centre and must use the documented board, pin map, supply, and logic level.
Buy / compare this part ↗Advantages
- Reprogrammable and reusable
- Large learning ecosystem
- Complex behaviour remains changeable
Limitations
- GPIO voltage and current are limited
- Some pins affect boot or communication
- Loads normally need a driver
Handling
- Disconnect power before rewiring
- Avoid static discharge
- Never power motors, relays, or pumps directly from GPIO
Specifications to verify
- Use the exact model, value, package, and rating listed for ESP32 or ESP8266; both are available (read ESP32 vs ESP8266); similar-looking parts are not always interchangeable.
- Confirm operating voltage, logic level, pinout, memory, USB interface, and maximum GPIO current.
What's this?Image, role, pros, cons, handling & specifications
Temperature and humidity sensors of the DHT22 or DHT11 kind
A named project component whose exact role is defined by the source circuit and build guide.
What it does hereIt performs a documented electrical, control, interface, or construction function in this project.
Buy / compare this part ↗Advantages
- Selected for this project
- Can be checked independently
- Supports modular troubleshooting
Limitations
- Substitutes may differ
- Generic names can hide variants
- Pinouts and ratings vary
Handling
- Compare the received part with the source
- Keep it labelled
- Do not force connectors or adjusters
Specifications to verify
- Use the exact model, value, package, and rating listed for Temperature and humidity sensors of the DHT22 or DHT11 kind; similar-looking parts are not always interchangeable.
- Confirm dimensions, ratings, connection method, polarity, and environmental limits.
What's this?Image, role, pros, cons, handling & specifications
PASSIVE LEARNING VIEWk Ohm resistor
A passive component sets current, voltage, timing, filtering, or signal behaviour without adding gain.
What it does hereIts exact value and tolerance determine how the surrounding stage behaves.
Buy / compare this part ↗Advantages
- Simple and dependable
- Low cost
- Easy to measure before installation
Limitations
- A wrong value can stop or damage the circuit
- Ratings must not be exceeded
- Polarized parts require correct orientation
Handling
- Measure unclear values
- Observe capacitor polarity
- Avoid overheating leads while soldering
Specifications to verify
- Use the exact model, value, package, and rating listed for k Ohm resistor; similar-looking parts are not always interchangeable.
- Confirm value, tolerance, power or voltage rating, polarity, and package size.
What's this?Image, role, pros, cons, handling & specifications
A set of jumper wires
A named project component whose exact role is defined by the source circuit and build guide.
What it does hereIt performs a documented electrical, control, interface, or construction function in this project.
Buy / compare this part ↗Advantages
- Selected for this project
- Can be checked independently
- Supports modular troubleshooting
Limitations
- Substitutes may differ
- Generic names can hide variants
- Pinouts and ratings vary
Handling
- Compare the received part with the source
- Keep it labelled
- Do not force connectors or adjusters
Specifications to verify
- Use the exact model, value, package, and rating listed for A set of jumper wires; similar-looking parts are not always interchangeable.
- Confirm dimensions, ratings, connection method, polarity, and environmental limits.
What's this?Image, role, pros, cons, handling & specifications
Schematic
A named project component whose exact role is defined by the source circuit and build guide.
What it does hereIt performs a documented electrical, control, interface, or construction function in this project.
Buy / compare this part ↗Advantages
- Selected for this project
- Can be checked independently
- Supports modular troubleshooting
Limitations
- Substitutes may differ
- Generic names can hide variants
- Pinouts and ratings vary
Handling
- Compare the received part with the source
- Keep it labelled
- Do not force connectors or adjusters
Specifications to verify
- Use the exact model, value, package, and rating listed for Schematic; similar-looking parts are not always interchangeable.
- Confirm dimensions, ratings, connection method, polarity, and environmental limits.
Connect one verified path at a time.
Explore the named components and standardized signal flow, then use Source Check to verify exact physical pins, values, and topology before applying power.
Trace this circuit.
DHT Temperature and Humidity Readings Displayed on the on- board ESP8266's OLED Display: interactive parts, standardized terminals, responsive anchored wires, student explanations, and the original circuit reference in one shared system.
Trace before wiring
Follow power, ground, inputs, processing, and outputs in that order. Never guess a pin from package shape alone.
Connect with power off
Make short, labelled connections and share a common ground only where the schematic requires it.
Inspect every joint
Check continuity, polarity, adjacent shorts, and loose connections before the first power-up.
Open all source diagrams and build views 3 visuals
Confirm the hardware-only control path.
This project does not include firmware in the source. The circuit itself provides the required behaviour.
How to connect
- Match every controller label to the circuit view and source pin map.
- Join grounds before signal wires when separate low-voltage supplies are used.
- Keep motors, relays, pumps, and other loads on a suitable driver and external supply.
Common mistakes
Reversed VCC/GND, board-label versus GPIO-number confusion, missing common ground, and charge-only USB cables.
Troubleshoot
Disconnect loads, continuity-test one path at a time, then test with a current limit.
Software preparation
No IDE, board package, library, or firmware upload is required for this project.
If you add a programmable controller as an extension, document its pin map separately.
How to upload code
The original design is implemented entirely in hardware, so proceed after verifying the circuit and supply.
Assemble, deploy, test, and troubleshoot.
Use the complete source notes in build order, then pass the final checks before calling the project finished.
Build in functional stages
- Power and regulation
- Controller or processing stage
- Inputs and sensors
- Outputs and loads
- Enclosure and strain relief
Power up safely
- Inspect unpowered continuity first
- Apply the lowest safe current limit
- Measure supply rails before signals
- Add one load at a time
- Record expected and actual results
Work from simple to complex
- Confirm power, ground, polarity, and orientation
- Compare each pin with the source
- Test inputs separately from outputs
- Replace only one variable at a time
- Power off before every correction
Follow the documented instructions.
These notes come from this project's source and remain in their original order.
Project overview
Project build note426.DHT Temperature and Humidity Readings Displayed on the on- board ESP8266's OLED Display
Discover how to read the temperature and humidity from a DHT11 or DHT22 sensor on an SSD1306 OLED display by utilizing an ESP32 or ESP8266 along with the Arduino IDE. The objective of illustrating how one may develop a physical user interface for their boards is the primary motivation behind combining the OLED display with either the ESP32 or the ESP8266. In this project, we will make use of an I2C SSD1306 128x64 OLED display. A DHT22 temperature and humidity sensor will be utilized in order to obtain accurate readings of the surrounding environment (you can also use DHT11).
Components Required
Project build note0.96 inches of OLED screen real estate ESP32 or ESP8266; both are available (read ESP32 vs ESP8266) Temperature and humidity sensors of the DHT22 or DHT11 kind Breadboard 10k Ohm resistor A set of jumper wires
Schematic Because the OLED display that we are communicates using the I2C communication protocol, you will need to connect it to the I2C pins on either the ESP32 or the ESP8266. The following pins will be assigned as the default I2C connections if you are using an ESP8266: GPIO 5 (D1): SCL
GPIO 4 (D2): SDA
Project build noteIf instead you are working with an ESP8266, go to the following diagram. In this example, the data pin of the DHT sensor is connected to GPIO 14, but you are free to use any other GPIO that is appropriate. Installing Libraries
Installing the libraries necessary to write to the OLED display and the libraries necessary to read from the DHT sensor is required to be done prior to submitting the code. Installing the OLED libraries When using an ESP8266 to operate an OLED display, you can choose from a number of different library options. The Adafruit SSD1306 library and the Adafruit GFX library will be utilized in this tutorial. Both of these libraries can be found on the adafruit website. To successfully install these libraries,
please proceed as follows
Project build note1. Launch the Arduino Integrated Development Environment (IDE), then navigate to Sketch > Include Library > Manage Libraries. It ought to start up the Library Manager. 2. In the search box, enter "SSD1306," and then install the SSD1306 library that may be found on Adafruit. 3. After installing the Adafruit library for the SSD1306 microcontroller, go to the search box and type "GFX." Then, install the library. Installing the DHT Sensor libraries We will be using the libraries provided by Adafruit in order to retrieve data from the DHT sensor. 1. Launch the Arduino Integrated Development Environment (IDE), then navigate to Sketch > Include Library > Manage Libraries. It ought to start up the Library Manager. 2. In the Search box, enter "DHT," and then install the DHT library that may be found on Adafruit's website.
3. After you have finished installing the DHT library that Adafruit provides, go to the search box and enter in "Adafruit Unified Sensor." To locate the library and to install it, go all the way to the bottom. Installing the ESP boards Since we'll be using Arduino IDE to write the code for the ESP32/ESP8266, you'll need to make sure the ESP32/ESP8266 add-on is installed in your copy of Arduino IDE.
Demonstration
Project build noteThe conclusion of this course is depicted in the figure that is presented below for your reference. Readings of both the temperature and the humidity
are displayed on the OLED.
You built DHT Temperature and Humidity Readings Displayed on the on- board ESP8266's OLED Display.
You followed the full workflow from understanding the mission to testing the finished project. That is a real engineering achievement - well done.
Temperature and Humidity Web Server for ESP8266 DHT11/DHT22 with Arduino IDE
Ready to reuse what you learned in another project from the same track?
Start this project →