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No you can't swap that at all. you need other libraries for the DHT22 sensor. please google a bit before asking :)

there are excellent how-to's on the net. even from adafruit like this one: http://learn.adafruit.com/dht

Sorry, this question was about the hardware not the software, hence the post being in the hardware section of the forum.

Could work just out of the box. Both use 1-wire, both use 4,7k resistor.

To be safe measure voltage level before trying it!

I just interchanged them (well just with a DHT11 I had lying around) at a Arduino breadboard against each other with same circuit but different library. Worked fine.

Thanks ToF, i'll give it try.

Please keep us updated!

I've not used the DHT22 myself, but I found these links which hopefully will help

Here is a previous post on the subject http://openenergymonitor.org/emon/node/2389, seems you can connect via the temperature sensor jack or pulse sensor jack.

The DHT22 page in the shop has also useful links / info http://shop.openenergymonitor.com/dht22-temperature-humidity-sensor-am2302/

and here is the sketch

Just to confirm that this works fine without any HARDWARE modifications required, other than using the DHT22 sensor of course :D

I used the 'emonTX LowPower Temperature Example' sketch for this.

As an added extra, I also fitted a NCP1402-3.3v step-up breakout board from Proto-pic to gain the required 3.3v for the sensor from 2 AA batteries.

Phil. T

The DHT22 will work fine with the low power emonTx if it's powered via usb since the DHT22 won't work much under 3.3v. As Phill mentioned above thus can be solved by using a step up converter. It would also be desirable to change the 4.7k resistor for 10k. I think the DHT22 might work with a 4.7k resistor but results might be unreliable.

Thanks for that info Glyn, I'll try and get that resistor changed tomorrow.

Phil T.

Fine.