DHT22

The DHT22 is a basic, low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analog input pins needed). It's fairly simple to use, but requires careful timing to grab data. The only real downside of this sensor is you can only get new data from it once every 2 seconds, so when using our library, sensor readings can be up to 2 seconds old.

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Node-RED Console for Teaching Physical Computing / AI / IoT

“Through Code Club I have come to appreciate the value of visual, no-code approaches to teaching computational thinking. I wanted to expand upon the physical computing education possible with a Micro:Bit and also to introduce IoT and AI to …

DIY Air Quality Monitor – PM2.5, CO2, VOC, Ozone, Temp & Hum Arduino Meter

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COVID-19 and PM10 Levels!

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Freezer Failure Alarm

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An ESP8266-based Temperature, Humidity and Line Voltage monitor

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Pandemic Dayclock with Indoor Air Quality Sensors

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Humidity Sensor Calibration

“This experiment will reveal ability measuring of Humid sensor DHT22, SHT21, BME280. Also mention about how to calibrate them I’ve got 3 sensors that can measure relative humidity of the air: BME280, SHT21, DHT22. They stated ability of measuring …