2 · Inputs & sensors
Temperature & humidity (DHT22)
Intermediate18 min
Goal
Read a digital sensor once every 2 seconds.
Why it matters
A digital sensor sets its own pace: reading too fast returns errors.
What you need
- Arduino UNO board
- DHT22 température/humidité
Nothing to buy: every component below is simulated in the browser.
Steps
- 01Add the DHT22 on pin 7.
- 02Read temperature and humidity.
- 03Space readings by at least 2000 ms using millis().
- 04Print both values on one line.
This tutorial runs inside the Circuitly simulator: your wiring and your code are checked automatically at every step.
Frequently asked questions
- Do I need to buy hardware for this tutorial?
- No. Everything runs in the browser: Circuitly simulates the board, the components and the code. Real hardware is optional if you want to rebuild the circuit afterwards.
- Which components are used?
- Arduino UNO board, DHT22 température/humidité. They are already available in the simulator library.
- How long does it take?
- About 18 minutes, intermediate level, in 4 guided steps.
- What should I know before starting?
- The previous tutorial in the series, “Ultrasonic range finder (HC-SR04)”, is enough preparation. No software install is required.
- Is the code provided and checked?
- The simulator checks your wiring and your code automatically at every step, and shows the commented solution if you get stuck.
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