Re: CM-11A Versus CM-15A

[Charles Sullivan <cwsulliv@xxxxxxxxxxxx>]

On Wed, 09 Dec 2009 17:28:50 +0000, David White wrote:

> Charles Sullivan wrote:
>> The calendar in the CM11A is just a 366 day counter.  For non-leap
>> years the ActiveHome software programs only 365 days, so on the 366th
>> day (Jan 1st), nothing works.  The counter will roll over to 0 the next
>> day and things will start working again on Jan 2nd, although a day off.
>> The day of the week, an independent 7 day counter, will continue to
>> operate correctly. So if you are doing the same things on the same days
>> of the week every week, you probably won't notice much amiss until the
>> date when Daylight Time starts.
>
> Interesting. I only noticed that stuff didn't work on the new year so I
> have gotten into the habit of re-setting the whole shebang on new year's
> day. I have never waited to see if things stated working again on the
> 2nd. Maybe I will this year just for grins.
>
>
>> The CM11A clock is always internally set to run on Standard Time, else
>> you wouldn't be able to run it disconnected from the computer all year.
>> There are no one-hour "jumps" in the times of Dawn/Dusk when measured
>> on Standard Time.  The ActiveHome software adjusts the programmed fixed
>> timers by an hour during periods of Daylight Time.  However since the
>> US Congress changed the dates of Daylight time in 2007, it's not clear
>> that ActiveHome can correctly use the new dates even when manually
>> entered.
>
> Yes, the "jumps" I mean are not caused by the CM11A but by how it is
> programmed by ActiveHome. On the statistics dialog one can see the
> "jump" in the times used for dawn/dusk at daylight savings. I haven't
> checked in detail but it did seem like ActiveHome was doing about the
> right thing with the DST. I recall having to do changes to Windows and
> it seemed like ActiveHome "saw" those changes. I will have to
> double-check though. In my case "close" is ok.

The Dawn/Dusk curves displayed by ActiveHome use Civil Time, i.e., wall
clock time, so Dawn and Dusk will show the jumps. The fixed times would
appear "flat".

If displayed using Standard Time, the Dawn/Dusk curves would show only
the stair-step approximations but no one-hour jumps at the Daylight Time
transitions.  The fixed times would have the jumps.

I haven't used ActiveHome in many years.  Have you found that it uses
the correct dates for the post-2007 Daylight Time transitions (either
automatic or manually entered)?  I'd be interested in knowing for sure
whether or not it's salvageable in this regard.

>> A lot of people are happy with the newer CM15A and ActiveHome Pro
>> software, but I found the firmware and/or software had more bugs than
>> fleas on a hound dog, and the more X-10 fiddled with it, the worse it
>> seemed to get.  I gave it up as a lost cause a year or two ago, but
>> that's just me.
>
> That's what I was afraid of. I'd rather stick with the devil known than
> spend more and get something even worse.

Before you give it up, check out http://forums.x10.com and see what
others are doing.  I'm more of a nitpicker than most, but many people are
happy with the CM15A and ActiveHome Pro.  A potential problem in sticking
with the CM11A is that it's now out of production and may be difficult to
replace if yours goes bad.

Regards,
Charles Sullivan

>
>> If you run Linux, Unix, or Max OS X, you can use the free Heyu software
>> (http://www.heyu.org) with your CM11A.  It solves both problems you
>> mentioned above.
>>
>>
> As a Windows guy, I can't use this. But I did look at it and it seems
> interesting. Thanks for your comments and time.