Re: xAP Configuration, Serial RS485 Bridge and PIC's

["g8kmh" <g8kmh@xxxxxxxxxxx>]

KH> I have long thought that a (nice low cost) embedded xAP BSC
Mapper would be the ideal. A standalone basic xAP engine implemented
on say PIC or Rabbit - with perhpas a config schema or web config
page. This would handle mappings, some logic (if then etc) and some
scheduling.   Then you can eliminate the PC altogether and could also
support 'press' 'release' type mapping in a controller so your
switches remain standard as one config.   Maybe using Phaedrus'
hardware and a different chip to make it such a device.

Indeed, this would also make the HA system more robust to PC failure.
Perhaps something for later....much later.
KH> At this point we have no xAP official configuration schema , what
> initially appears easy becomes a surprisingly complex area to
accomodate
> anything but the simplest of devices/parameters - plus it requires
that
> all configurable devices be transceivers -  we need something more
> capable than the alternatives out there.    This is an interesting
area
> for someone to take up the task  ;-)    James did a lot of work on
this
> and it's almost there , but not quite....  FTTB however you can
always
> set up your own schema to configure your own devices including the
UID
> if necessary. It is expected most people will do this either via
xAP
> messages, a web config screen or in some cases only switches.  The
UID
> is powerfully & extensively used in BSC, indeed it's the
cornerstone
> that makes it possible. UID's also offer the ability to detect
sources
> based on 4 bytes of stored data. Very useful for small memory
devices,
> automation controllers and groups and scenes.
>
> *******************
> Actually having an agreed standard way to configure the key
parameters
> (UID , source address,  hbeat interval etc) - ie the header values
is
> probably very easy and we should at least have an interim schema
> solution pending a full config schema. This probably can extend to
sub
> address names too.  What do people think ????
> *******************

Absolutely. Anyway I can help I will. I'm not sure about the
transceiver argument. Most devices will (BSC have to?) respond to
queries anyway.
> Ahh I think you may have misunderstood the UID in this respect - no
> device can 'respond' to a UID as it is not in any way targetable. A
> message can't be sent to a UID.  You can only target the longform
> address using target= .  The reason for this is again that
wildcarding
> wold fail (be bypassed)  if you were allowed to directly target a
UID  .
>
> eg a device is listening for all messages sent to  X10  by applying
a
> filter of 'target= *.X10.>:>   and it sees a message targeted at
> FF123400  is that being sent to an X10 device ??   You can't tell.
>
> However a device can recognise a sender (at either the device or
node
> level) based on just the 4 byte UID. Hence a device monitoring a
group
> of triggers eg a lamp that is operated by 4 different light
switches
> need only store 16 bytes of data - indeed possibly only 8 bytes if
you
> can afford to ignore the first byte (network) and last byte
(subaddress)
> in your particular implementation.

OK, I'll put it another way. I'm a xAP dumb light dimmer. Single
channel, zero crossing triac, etc. Which UID is the lightswitch(es) I
should listen for? If I've made 40 of them, how as 'small' devices do
they get the source UID(s) they should listen for programmed in? (and
for the moment assume it's so dumb it can't parse the header fully)

With a config schema and a broadcast UID it becomes easier. The
device always listens for the broadcast UID and a config message
(perhaps a one shot) can then send the other UID's it should
listen/filter for (in this simple case of course it only works with
one device listening!). If this can't be done and the device has to
parse the target address then UID's are mainly redundant anyway.

Actually it may be acceptable to commission in that way. Connect one
at time, send the one shot commission/config message, move on. If a
reconfigure is required then it would have to originate from one of
the programmed UID's.

Lehane