From: James Sentman <james-AT-sentman.com>
Date: 15 May 2008 08:33:50 UTC   (12:33:50 PM in author's locale)
To: xtensionlist-AT-shed.com

On May 15, 2008, at 11:45 AM, Rob Lewis wrote:

> OK, let me take a shot at decoding this (James, you may have been
> spending too much time around Unix geeks :-)
>
> --Somebody (such as, for example, me) writes code to execute on the > Arduino. This code looks for events on its sensors and reports them > over the USB bus.
>
> --Somebody else (such as, for example, you) writes code to run on
> the Mac. This code receives the reports from the Arduino and … what,
> exactly?
>
> Aargh, I'm lost again.
> --Where exactly does your "conduit" run? Is it part of XTension?
> --Where does the Arduino API run? In the Arduino microcontroller
> itself?
> --Is this a 2-way interface?
> --What does "in our arduino work" mean exactly?
> --Where does the proposed command "XTTurnOn" occur? In unit scripts? > Why is it needed over standard XTension verbs?
> --It sounds like you are proposing mapping X10 unit addresses to
> inputs and outputs on the Arduino board. Am I close?
>
> Waaah! Maybe a block diagram would help :-{
>
> (Want to continue this offline?)

I think you're making this too complex ;)

i thought it would be interesting to provide a way to easily get
information about units from XTension to the arduino board, and get
information out of the arduino board back into XTension.

THink about how you would do that now. Say you wanted to have a unit
in XTension turn on an LED connected to the arduino board. Well, you'd make a pseudo in XTension with an applescript that told some
scriptable serial port device to write something to the serial port
that the arduino was connected to, then you'd write some code on the
arduino that read that serial data, parsed it out into useful bits and figured out what to do with it. To go the opposite direction you'd
have to do something similar. a contact closure connected to the
arduino causes a bit of your code on the chip to run, that would write some data up the serial port which would be read by the scriptable app that was connected to it, which would read it, parse it out for useful bits and applescript the pseudo in XTension again? This gets all very complicated in a hurry ;)

What of instead of just raw "write some series of bits to the serial
port" on the arduino, it actually had a command that you could just
call that said "set the value of XTension unit B1 to 175" and that
took care of talking up the serial port and communicating with
XTension. Thats all I'm suggesting. Almost anybody here could write
enough arduino code to do that! But it would take quite a bit more in the way of chops and patience to design your own serial protocol to
handle that and then write both the arduino portion and the
applescript portion on the host to do it, plus then yo'uve got lots of programs and bits and pieces in the middle and it gets complex and
easy to get hosed up.

I think it should be possible to provide an interface in XTension that interfaced to some starter code that we could provide as a starting
place for arduino work. So that if a unit is controlled in XTension a very simple method is run in the arduino automagically by this code
allowing you to turn on and off something with just a line of code or 2. The opposide direction would be just as easy.

So we provide the "verbs" in the arduino itself for controlling
XTension and being controlled by XTension and then YOU customize those in any way you like.

So now instead of designing a serial protocol and writing a bunch of
complex bit parsing code on the pic chip in there, you're writing
something much more similar to what you do in XTension. Oh, I got an
ON for A1, so I want to turn on digital IO pin 3 or something like that.

We could even do a basic setup out of the box which provided some
basic simple input/output control... I'll have to re-read the
documentation now to see what is possible. But perhaps it begins to
make sense? I'ts like just a data capture system, but it could be so
much more if you wanted it to be.

-J

Thanks,
James

James Sentman sentman.com MacHomeAutomation.com