What it is and how it works
The kit includes one DHT11 temperature and humidity module. It converts surrounding air conditions into digital information read through a signal line. Temperature describes how warm the air is; relative humidity compares the water vapour present with the amount possible at that temperature.
DHT11 is suitable for learning about slow changes in a room. It is neither a precision reference instrument nor a fast sensor. A library handles the timing-sensitive communication, but the program still needs to distinguish successful readings from errors. An invalid reading should not become a displayed temperature of zero degrees.
What we can use it for
- Make an OLED room thermometer and humidity display.
- Record conditions before and after airing a classroom.
- Turn on an LED when a reading crosses a selected demonstration threshold.
First exercise
In a stable room, print temperature and humidity every few seconds. Include a message for failed readings. Compare several measurements and record the sensor position instead of drawing conclusions from a single number. Then move the display to the OLED.
Handling notes
A module board and a bare DHT11 may have different connectors. Check VCC, signal and ground, the required pull-up resistor and whether the signal is pulled up to 5 V before connecting to ESP32. Follow the sensor and library guidance on intervals between readings. Keep the sensor away from the board's warm regulator, direct sunlight, water and condensation.