DMX and xPL

["g8kmh" <lehane@xxxxxxxxxxxxxxxxxxx>]

There does seem to be a lot of DMX information and equipment about.
So it would seem a good starting place for lamp dimmers, which at a
low level is probably one of the more useful HA functions. There is
the schematics and code for a PIC at
http://www.geocities.com/ph_zone/Digi_Pack/Digi_Pack.html
and this
could be extended to more channels easily, as well as ditching some
of the other features. Secondhand units also seem to be reasonably
available at lower prices per channel than C-BUS.

Philoshically it would be ideal to extend xPL onto dumb devices. A
couple of downsides to a PC based parser revolve around the fact that
a light switch (say) will need to send a message to the parser and
then the parser (or script/determinator) will resend it back out. No
PC, software or microcontroller = no lights. With xPL on the, say,
CAN bus then a switch could be configured to send an xPL command to
the lounge lights also on the RS485/CAN bus but also picked up by the
PC interface and used to run scripts, etc. Yes, the switch would need
enough smarts to be able to be configured but that's not too tough.
Now, that kind of breaks the xPL schemas since a switch should use
sensor.basic - is it 'legal' for a switch to issue a control.basic
command as well as a sensor.basic trigger?

CANbus does start to look attractive and vscp or yasp as the low
level protocol, although I'm sure there are others!

The reason for the original point was that we're doing major building
works and an extension next year so have a clean slate. X10 isn't on
the shopping list :)

Lehane