There are ha systems that do this already. There's nothing special
about controlling the mains, you just have to take a bit more care.
> The system would be centrally operated, but the control system would be
> modular and
> independent of the central control, right? My question is this. How
> much automation
> would be involved? How sophistocated would the automation be? This is
> where the
> protocal would come in.
>
> If someone could maybe post a protocol that's already been
define, maybe
> there would
> be some direction we could all head towards.
>
> I hope I'm not hogging up the discussion here.
>
That's pretty much what we have to answer here. The control
system may be independent of the central control, but not
necessarily. I also think we need to make some terms clear.
"central control" we should probably refer to as the "house hub."
(Anything that sounds catchy or neat I automatically assert a
copyleft on and grant all rights to this group. I also grant a copyleft
to "Home Brew Home Automation" which is what I called it on the
web site. But I digress.)
The house hub is the central point of connection; it probably will do
little or no control of its own unless there is no other controller
present. Then it should probably have some rudimentary logic in it,
but I have no idea what form this logic should take.
Throughout my entire tenure here, I am going to hold my ideas up
against the framework of the house that I am designing. If I appear
to be wandering too close to something that sounds suspiciously
proprietary or stupid, please let me know. However, my wife and I
have had a house on the drawing board of our mind for about 6
months and we are, hopefully, within a few months of beginning
construction. This house will have home automation in it as a large
part. Here's hoping we can get some specs together and maybe
even a parts list before I have to go buy the stuff I really have been
lusting after...!
Functional description/Physical Layer
The central point of control should be a house hub. This hub
should sink a multitude of signals from varied sources, and provide
sources to controllers, monitors or other devices.
The house hub should be adaptable to any type of source,
including carrier-current (X-10) or direct low-voltage wiring. This
therefore presupposes an interface module. Do we say that the
house hub accepts a certain type of input as a default and if you
are using another transmission protocol, you add a different kind of
box?
If so, then simplicity pretty much demands that the carrier-current
people lose. If you're running X-10 interfaces, you will need to plug
in modules to interface with your X-10 units.
It's revelation time. I work for Lucent Technologies. As in the
company that recently introduced the Home Wire spec and is
partnering with Tut Systems for an HA solution using standard
phone wire. (I do not work in that business unit. I work for the
Microelectronics group -- we make semiconductors and
optoelectronics -- and I do EDI and electronic commerce.) I don't
want my Lucent affiliation to pop up in an untoward fashion and I
certainly don't want people to think I'm deceiving them. I will not
reveal any proprietary Lucent secrets (not that I even know any) :-{)
and I have no financial interest in Lucent's home automation
system so our secrets are safe with me.
Hope nobody has a problem with this.
Anyway, I bring this up because I remembered about the house
wiring. :-{) Should we decide that we want to try and run this HA
system on the residential phone wiring in the house, or should we
demand pulling Category 5 data cable? The latter is obviously
easier, except in old houses where pulling cable isn't practical.
Finally, my last point refers to a post from Robin where she mulls
over using IP/UDP for the network layer. It's a small detail, but it
got me excited. We could take the Class A non-routable address
(what is it -? 10.x.x.x) and somehow work the octets such that the
last one will define a family of like devices, the 2nd-to-last octet
would be a group of families (IOW "light controllers", "temp
controllers", etc.)
Well, that's it for now. I'm getting incoherent and I really need to
get my sleep.
-- Over the router and through the bridge, to grandmother's page we go!