1-wire & HobbyBoard (et al) -- First 1w project! Recommendations?

messypotamia

New Member
My project is to install a couple temperature sensors (an underwater sensor based on the DS18B20, as found at [ link was here... PROHIBITED cuz I'm NEW? It is a probe w/ 2m sealed cable] )
So I'm going thru owfs.org's site and clicked through all their Intro pages (1 of which has some of their vendors, 1 of them is HobbyBoard), and it's starting to make sense... the data bus is pretty self explanatory (used to work R&D airborne instrumentation so data busses aren't new to me), I need a bus controller, sensors, and a 1w USB adaptor (will plug into RPi B+ ). So I get ready to think about ordering and what seems like an important component to me, the 4-port Hub, isn't available, hasn't been available, and an online inquiry to HB resulted in them responding "we don't know when it will be available".
So is there something I don't understand? If I want to create a 1w bus, don't I need a 1w bus?
 
I want a couple waterproof (preferably with 2 - 3m sealed leads) temp probes, and eventually some other 1w probes/sensors, and put it on a 1w bus, and hook it to my RPi B+. 
 
What do I need? Where should I get it? Should I just wait till HB has the Hub in stock or is there someone else?
 
Thanks for your advice!
"MP"
 
Sorry ... Meant to say "If I want to create a 1w bus, don't I need a 1w HUB" ?  //meaning I believe the Hub acts as the bus controller, and connects to my RPi//  -- please correct me if assumptions are wrong, thanks --
 
The USB adapter is the bus controller, more or less.   You don't need a hub.
http://www.hobby-boards.com/store/products.php?product=1%252dWire-USB-Adaptor
 
You only need a hub if you want to split up your 1w bus into multiple segments for topology and/or function.  For example, I put my attic temp sensors on one segment, and my HVAC temp sensors on another, and weather sensors on another.  If you use a hub, you need to make sure the software supports it.
 
I have a older 6-channel hub from 2007 and it worked great when I was playing with this stuff.
No experience with the newer unavailable 4-channel or the new master and wireless master hubs.
 
Hubs are not used with 1Wire devices, possibly splitters. Typically they are designed for daisy chain topology only but some have extreme reliability with star topology. One ISY994i HA person is using an Autelis box with a single 1wire interface, combining star and daisy chain topologies, using over a mile of cable to temp sensors all over his house and HVAC system, stuffing the results into his ISY over Ethernet, all built into the Autelis box and claims he has never missed a stroke yet.

The reliability is mostly dependant on the 1wire interface. Some not so good. Some never hiccup. All devices need to have specifically written interrogation drivers to use any sensor. None are generic.
 
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