RE: xAP switch

[Ian B]

Hi Steve

The relay board controller I am working on currently has 8 inputs. These
are
switches than can be momentary or locking. The program lets you configure
whether a message is sent on the input going low, high or both. I also use
a
Maxim chip (max6818) to do all my debouncing which saves a lot of
processing
time.

It would be quite easy to modify the program to just send input changes and
even make a new PCB for it. Having said that the board has 8 open collector
outputs which folks might find useful. There is also RS485 and serial on
board although only one can be used at once. You can see the current
prototype on my site under projects then relay board controller. Note the
'production' version will not have the switches on board. They will be
connected by a plug of some nature so can be remote.

I have been thinking of adding another 8 inputs, not for any reason other
than I can. Well, that's not quite true. Since this is designed to control
my relay board and I am thinking of using them at home I might need more
than the current inputs. This might be for travel limit sensing for
example.
We shall see.

All this is done on an Atmel chip using the CodeVision compiler. I found
PIC's became unreliable and space became tight once I got beyond the first
page of memory.

Ian

>-----Original Message-----
>From: Kevin Hawkins [mailto:<a
href="/group/xAP_developer/post?postID=-O7hHn0Nzp8kfgIJPY3VHIdnDZHG1Y_QIKk4S4_1-PlrfyJet-HTDrBgyHeBHpx6k5Hg38ue1WblywIMjxgR-w">lists@u...</a>]
>Sent: 14 April 2003 12:17
>To: <a
href="/group/xAP_developer/post?postID=sndT6bw6H4s7LpESJQm9mHUvXjAuDiXbfPJAQZmgGLJoit9X1WiRjcvauQ9h17T6LgPQpVqHfbXL7o3yEb1XqPI6WD9B9Q">xAP_developer@xxxxxxx</a>
>Subject: RE: [xAP_developer] xAP switch
>
>
>Basic switch functionality to send xAP messages can as you say be done
at
>any level of complexity. The lightest implementation could just
effectively
>send an ON or OFF state based on switch change and all you would
>really need
>is to alter the last two digits of the UID to represent each switch on
one
>unit. (It would have to transmit it's xAP source address 'text' as well
of
>course).
> A receiver could also be very lightweight if you wanted just
>monitoring the UID to know when your switch has changed state - this is
one
>of the great features of the UID facilitating an absolutely
>minimal receiver
>complexity. However this would not support wildcarding if you needed
that
>feature.
> The choice of coding several xAP message types into the transmitter
>or not is really one you personally have to decide. You could achieve
the
>same by monitoring a particular switch (or switches) from the xAPp
>receiver,
>and as the receiver may already be a PC based application this might be
>easier code wise. In my view switches should provide basic switch type
xAP
>functionality and loading them with additional functionality may prove
>problematic to maintain as you system expands. If you had several
switches
>each controlling one device they would all need updating 'code wise' if
and
>when the destinations changed. Really you should just be updating
target
>addresses on the switch rather than the format of the messages
themselves I
>feel.
> It sounds like your real decision here is based on whether you will
>envisage using some form of xAP controller in your setup in the long
term -
>a central co-ordinator for exactly this sort of issue that might
provide
>some mapping of sources to destination. Really an issue of if you will
have
>a PC running 24/7 and if you are happy with reducing your reliability
down
>by becoming dependant on such a controller for the system to work
(ignoring
>the possibility of having a backup/redundant second controller). The
system
>would be far more resilient if you supported a direct source to target
>linking (or even a wildcard variant) and I guess (thinking as I type
here)
>that incorporating the filtering in the target xAPp's might be easier
and
>the approach I would take.
> Ian B's xAP relay board has some switch inputs IIRR - you could use
>one of these - indeed maybe Ian could consider offering an input only
>version for exactly this purpose (essentially a partially populated
board).
>A Clipsal C-BUS switch would also do this via the xAP gateway and is
>cosmetically appealing.
>
> I too am interested in the state of any PIC based xAP framework....
>
> Kevin
>
> > -----Original Message-----
> > From: <a
href="/group/xAP_developer/post?postID=2UgkCSQocpULgcPXOgEX1bm6ogRav6AQg24u7JdnwixyPJtMPVDxT_UAF13c7w5tXnb99gm2gMGa4Pw_QOhgcOny">steve.cooper@u...</a>
[mailto:<a
href="/group/xAP_developer/post?postID=2UgkCSQocpULgcPXOgEX1bm6ogRav6AQg24u7JdnwixyPJtMPVDxT_UAF13c7w5tXnb99gm2gMGa4Pw_QOhgcOny">steve.cooper@u...</a>]
> > Sent: 14 April 2003 11:20
> > To: <a
href="/group/xAP_developer/post?postID=sndT6bw6H4s7LpESJQm9mHUvXjAuDiXbfPJAQZmgGLJoit9X1WiRjcvauQ9h17T6LgPQpVqHfbXL7o3yEb1XqPI6WD9B9Q">xAP_developer@xxxxxxx</a>
> > Subject: [xAP_developer] xAP switch
> >
> >
> > Hi
> >
> > Been out of the loop for a while as we have been rewiring and
> > decorating
> > our house. Anyway just starting to catch up again and last night
> > thought
> > of an ideal xAP device.
> >
> > What I need is to have keypad at different points round the
>house. For
> > instance in the bedroom I could do with a small keypad stuck to
the
> > wall
> > that will arm the alarm to night mode, change the volume on the
Rio,
> > trigger the headline and news to be read over the speakers,
switch on
> > the
> > bedroom lights.
> >
> > My thought was either to make a xAP switch device that sends
>out a sort
> > of
> > I'm switch unit A and button 1 has been pressed, then let a
controller
> > device on the PC translate the xAP message from a switch xAP
>message to
> > say
> > a Rio or Comfort type xAP message. The alternative is to program
the
> > switch with the ability to send multiple xAP messages types
>up front so
> > it
> > send the correct message out straight away. The later sound
>better but
> > requires a bit more coding space and I was thinking of just
bashing it
> > out
> > on a PIC. Any views?
> >
> > Also are we anywhere with the PIC developer code framework based
on
> > Patrick's success with xAP message detection and heartbeats.
> >
> > S.