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Author Topic: Dht22 arduino libary ?  (Read 654 times)
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Hi Im using the arduino DHTLib with multiple dht22 sensors however its a bit slow every time I take a read of the temperature and humidity which is every 2 sec.Is there a library available that wont cause as much of a delay when I read the data from the sensor?
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The DHT22 has a maximum .5 Hz sampling rate - once every two seconds.  Nothing in the library can change that.
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The 2 seconds delay is in the datasheet, you may shorten this delay but you should know you're operating outside the formal specification.
It might work e.g. 1 second intervals or even shorter, but there is no guarantee.

Is the temperature / humidity of your process changing so rapidly that you need a faster measurement?
For temperature you could consider the DS18B20 which is at the same precision about 10x faster.

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Rob Tillaart

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