Re: xPL...1 Wire

[Ian Lowe]

----- Original Message -----
From: <<a
href="/group/ukha_xpl/post?postID=-BWrG8UXQcq879LrZ_Lh845-vD0-i_5c9lDlIO-btFdDHuTCp5fEpWGptYY0MjQrM83SIy-pnDY2ghDYkXzu7Tc">steve.cooper@u...</a>>
>
> 1) No need to, the best way to achieve zoning is to use DS2409 that
have a
> main and aux line. You can switch on individual DS2409's either main
or
> aux so that part of the 1-wire network is exposed to the master. You
just
> put all the devices for each zone on the main line and put a 1-wire
memory
> chip on the aux line with the zone name programmed into it. When you
want
> info for a particular zone you just switch on that DS2409 which will
> disable all the other DS2409 for other zones then switch on the aux
line
> read the zone name then switch over to the main line and read the
various
> 1-wire devices.
>
> 2) Easy enough to do the device id includes a device family code which
> tells you if it's a temperature sensor, memory, iButton type etc. So
you
> know what to do with it. In a zoning example you would just search the
> 1-wire network for DS2409's that way when you plug in a new zone with
a
new
> name it just picks it up automatically.
>
> 3) &amp; 4) See above the way I would see a 1-wire to xPL network
working is
> that you could specific up front that the topology must be zoned with
all
> devices hanging off of DS2409s. You could then start by releasing a
> temperature sensor xPL master board then later upgrade the software so
it
> would report other 1-wire device either via a new board or just a
program
> upgrade. Once you start supporting two many different devices you may
find
> you outgrow a PIC chip though. As an example I have some code that
will
do
> a full 1-wire search and report ID back that is about 1200 bytes.

I'm sensing a "been there, done that, got the T-Shirt" expert
lurking in the
background here ;)

It's kinda obvious that myself and Frank are scrabbling around in the
simple
end of the 1-wire pool, but it's probably worthwhile as a learning
exercise.

What do you suggest as a way forward Steve? are you happy to act as a
technical mentor, casting an eye over our suggestions?

Can we tempt you to start building yourself? ;)

As a precursor, do you feel 1-wire can be viewed simply as a transport, and
leave the nitty gritty of working the bus etc to the gateway device/app, or
do you feel that 1wire is enough "meat" in and of itself to
justify a
separate schema?

Ian.