Author Topic: 1-Wire Microlan  (Read 1846 times)

Offline DaveL17

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1-Wire Microlan
« on: May 05, 2013, 09:43:51 am »
I'm using EDS OW-SERVER-ENET2: http://www.embeddeddatasystems.com/OW-SERVER-1-Wire-to-Ethernet-Server-Revision-2_p_152.html
and the Plugin: http://forum.micasaverde.com/index.php/topic,8381.0.html

Starting to put together ideas of making my own environmental modules instead of buying these: http://www.embeddeddatasystems.com/OW-ENV-TH--Temperature-Humidity-Sensor_p_168.html

How about:
- Temperature/Humidity sensor: DHT21 ($5.00 on eBay) [or SHT11 or SHT25]
- 23mm x 12mm breadboard ($2.00 on eBay)
- Small project box ($2.00 on eBay)

Does anyone have any experience with the DHT21 (or SHT11) humidity sensor with the EDS?
Are there better alternatives for humidity in combination with a DS18B20?

What do 1-Wire folks use for homebrew environmental monitoring?

Offline Chris

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Re: 1-Wire Microlan
« Reply #1 on: May 05, 2013, 11:00:20 am »
The DS18B20 are good temperature sensors, but unfortunately there are no one-wire compatible humidity sensors available. The DHT21 is not one-wire compatible.

I don't think there are a lot of options for humidity - I've seen some code for a pic that can emulate one-wire devices, so you might be able to get something like that working, but when I looked a year or so back the code wasn't very complete.

For temperature, use the DS18B20. For humidity, I suspect you're stuck with the commercial options (which while they aren't especially cheap, they are no more expensive than Z-wave, and they are a lot better!). Or maybe someone will pop up with some other option...

Chris

Offline DaveL17

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Re: 1-Wire Microlan
« Reply #2 on: May 05, 2013, 12:46:58 pm »
Quote
The DS18B20 are good temperature sensors, but unfortunately there are no one-wire compatible humidity sensors available. The DHT21 is not one-wire compatible.

Thanks Chris - you've saved me some grief.  I did some searching to see what the OW-ENV-TH used for parts, but came up empty. I wonder if the EDS device has some on-board processing to convert a digital humidity sensor into Maxim 1-Wire compatibility...  I presume then that the SHTxx sensors are also not Maxim compatible?

Quote
For temperature, use the DS18B20. For humidity, I suspect you're stuck with the commercial options (which while they aren't especially cheap, they are no more expensive than Z-wave, and they are a lot better!).

True enough, they're not more expensive than Z-Wave, but I was hoping to be able to DIY something a lot cheaper and roll out a bunch of them! :)

Quote
Or maybe someone will pop up with some other option...

I hope so!

Thanks again,
Dave