DHT11 Temperature and Humidity Sensor

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Does it support plain “one-wire” ? Is it possible to use it with the GHI OneWire class ?

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I have looked in many places and I am not able to know if that sensor uses Maximm/dalas “one wire” protocol! :wall:

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Looking at the arduino code here: [url]http://sheepdogguides.com/arduino/ar3ne1humDHT11.htm[/url] it does not use the onewire protocol. As far as I know, all onewire devices have an address, and surely the DHTxx doesn’t.

Eric

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You mean SHT11 not DHT11.
Check out http://www.fezzer.com :wink:

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@ Joe There are two DHT11 single wire (D- robotics) and SHT11 two wire ( sensirion )

I think there’s drivers for both…

Cheers Ian

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Guys, I found the SHT11 stuff on Fezzer, but I am interested in the DHT11. It does use a one wire protocol - no clock pin. A search for DHT11 on Fezzer does return any hits.

Some web posts declare that it would be impossible to do this on a managed C# device (on a Netduino) - of course, I expect that we can do it with Fez. It needs 50us timing, but surely we can find a way.

I will keep working on it, but does anyone have any code working?

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OK, I am working on this. I do think it will be possible to read the signal fast enough using a trick or two (I mean an appropriate algorithm ;)). I will post details when I get it running, but if anyone has working code in the mean time I would love to see it.

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A driver is now available here : http://code.tinyclr.com/project/289/dht11---temperature-and-humidity-sensor/