Re: XTB-II Enhanced Repeater

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Jeff Volp" <JeffVolp@xxxxxxx> wrote in message news:iRzEi.77842

> >> I've been trying to make this the best X10 repeater available.
> >
> > Don't take this the wrong way but as an owner of the XTB-II that's not
> > going to be upgradeable to the XTB-IIR the subject of the world's best
> > repeater is primarily an academic one for me now.  On the other hand,
> > my interest in house-wide, real-time X-10 signal strength readings and
> > broadcast storm detection are quite high on my list, hence my discussion
> > of the details of  that project in the "broadcast storm" thread.
>
> While there are certainly some features that cannot be ported over to the
> 8-pin PIC, things like enhanced error detection, abort transmit on
> collision, and command storm shutdown can be.  It may also be possible to
> add the smart bright/dim repeat for sequential commands.  The real
question
> is whether it is worth the effort if only a few people are interested in a
> firmware upgrade.

It depends on a lot of things.  The most important, to me at least, is
whether the upgrade is simple to perform and bulletproof.  Even if you
volunteered to do it for a fee, the XTB-II is a critical component to be
missing from a house for very long.  You've got a wide range of customers
from those with no electronics experience to whose who could reprogram the
PIC without blinking.  That's a factor that will determine at least some of
the upgrade decisions.  Based on my experience with PC firmware, upgrading
is often an iffy proposition.

Then there's the issue of whether they'll need those features.  Polite mode
(abort on collision) is nice, but it could be a liability as well as an
asset.  If it fixes the rare cases where two transmitters send an X-10
command simultaneously, it's an asset.  If it however fixes a problem that
shouldn't be happening in the first place, it may be a liability in terms of
discovering and fixing the colliders, at least for me.  I'd want to know if
the repeater was being polite more than a few times a day.

(You've alerted me to the need to add such detection capabilities to the BSD
cradle.  I need to monitor the "X-10 Good" LED and the two or more segments
of the ESM1's bargraph LED for collisions and send a message, light an LED
or take some other action to alert me that more than a handful of collisions
a day are occurring.)

If you're still looking for features to add to the XTB-IIR, a way to read
the incoming signal strength and to alert the user to an unusual number of
collisions would be nice to have for most people, although perhaps not for
me.  I am afraid that the BSD would probably conflict with the XTB-IIR
because the IIR might detect and shut down the broadcast storm before the
BSD ever had a chance to detect the storm and sound an alarm.  It would
depend on whose time limit was set shorter.  I believe you've allowed for
different broadcast storm lengths in your device, so if my timing and yours
are both variable, that should be a problem that's easy to work around.

I also realized that detecting a broadcast storm has some interesting issues
associated with it, namely making sure that a legitimately long string of
X-10 commands doesn't get misinterpreted as a broadcast storm.  In my case,
I'll have to make assumptions based on the way the ESM1 parses the X-10
command.  It's only after the bargraph LEDs go out that the "X-10 Good"
detector lights.  I'm working on setting up my Sanyo CCTV recorder to film
the ESM1 display as it reacts to X-10 traffic.  Since it allows for very
high speed capture, with frame by frame viewing and millisecond time
stamping, I should be able to make very good estimates of how long each LED
stays lit and the exact on and off times.  It's probably overkill, but I've
found that examining reams and reams of raw data can often point out the
nasty exception cases that often prove quite troublesome to resolve after
the design is complete.

Sorry.  I'm hijacking your thread again.  (-:  It's hard to avoid because
discussing the XTB's functions naturally links up in my brain to the
sketching out the full spectrum of the BSDs capabilities that I've been
contemplating. I want to try to get it right in "wetware" before I go
soldering any wires.  (While writing this, I had the "ah ha" experience
about how I need to set up the TV remotes which I'll describe in another
thread.)  Even this tiny project has given me a greater respect for all the
time and effort that's gone into building the XTBs.  There must have been an
incredible number of decisions you had to make regarding component size,
cost, operation, interactions, etc.  The BSD universe is quite tiny by
comparison and yet it is still perplexing.  Every time I think I'll do X,
either some design constraint or unexpected behavior means I have to do Y.
Which leads us right back to your quandary:  To upgrade or not upgrade the
XTB-II?

Since most of the transmitters I use now for extemporaneous commands
(ControlLinc Maxi's) have polite modes, it's probably not terribly important
to have it in the XTB-II.  But it would be nice to have for the few devices
that still collide.  If I need the IIR, I'll just remove the II and use it
as a standalone device.  It's not as if the newer IIR obsoletes the original
unit into worthlessness.  So far, the HAC-8X8 switcher works fine with the
TW-523 plugged into the XTB-I outlet so perhaps when I finally get the
CPU-XA doing something useful again I will use the II as its powerline
interface.

Getting back to original question of who wants the upgrade, you're the only
one that's got the XTB customer list, so if you're losing sleep over the
upgrade you know who to ask!  I realize that it's the kind of question that
you might not want to ask because the (legitimate) fear is that everyone
will answer "yes I want it" and then never follow through.  So I'll quash
those expectations here and now by just saying "no."  (-:

If I need the better repeater, I'll buy it from you because I know you're
not buying a fleet of huge flatscreen TV's based on the profits you've made
on this venture.  I shudder to think how small a TV fleet you could actually
buy with XTB profits.  When I look at the cost of switching to Insteon or
Z-wave, which I was seriously considering before the XTB arrived, it's still
quite a deal even if I have to buy another repeater.  I just snagged a whole
bunch of X-10 gear from Ebay NIB at 1/4 what I used to pay from Worthington
so I'm not unhappy about passing that savings on to you by buying the IIR.
If I didn't have the XTB's, I would be paying a lot more per controlled load
than $5 and I would have perhaps 1/4 the overall capability and choice of
components.

The XTB-II's had their purpose.  It's reasonable to make people buy the IIR
if they want a super-duper, "handles all cases" repeater.  There will be at
least a few grumblers out there that won't agree, but if I were you I would
consider the cost of porting the IIR code to that of a quiet trade-up
program for any extremely noisy and unhappy XTB-II owners.  Not sure what
you can do with the returned XTB-II's, but I am sure that over the years at
least a few will be fried by direct lightning strikes, home fires, etc.
I'll bet you could do the trade and sell the used ones cheap on Ebay and
still sort of break even.  It all depends on the value you place on your own
time.  You couldn't get me to do much of anything for $1 an hour.

So the bottom line is, no, I don't think it would be worth the effort to
port the code.  Even though I would like to have it, there are good business
reasons not to, mainly because your time is probably better spent perfecting
the XTB-IIR.  If there were no other uses for the retired XTB-II, I would
feel differently, but there are.  Also, since you inspired me (and led me to
a great vendor, Fruit Ridge Tools*, for the parts) to use a twist-lock
220VAC outlet to mount the XTB-II, there's very little switchover cost
involved between the two devices.  FWIW:

* "Fruit Ridge Tools specializes in electrical surplus tools and supplies.
Offering a wide variety of switches, dimmers, plugs, wallplates, etc"  Also
has a store on Ebay.

www.fruitridgetools.com/

(No commercial interest or kickbacks involved, just a fairly priced and very
helpful merchant.)

--
Bobby G.