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[roger1818]

It would be nice if the firmware in the
LM465 Lamp Module could be updated so that
it can be brightened from off without going
to full brightness first.  I know that this
is available in the LM14A and there is a
workaround where you dim the module to zero
instead of turning it off, but this would
be an easy update that shouldn't require
any hardware changes.

[donald mcmow]

It would require that you change the
firmware chip to make the required command
available. Since this chip is soldered onto
the board it is a little more difficult
than you think. It would be better to
utilize it in a location that would not
require you to use the dim function or
where it would not matter.

[roger1818]

Donald:  I am not suggesting they retrofit
existing lamp modules but only new ones
that are manufactured.  The way they have
had the RCA overstock promotion on for over
five years now, I have to wonder if they
haven't had a new build in a long time.
This might explain why they haven't made
any improvements to it.

[dave w]

Roger H: Am I missing something here? If X10
gives LM14A features to the LM465 they will
have to start charging LM14 prices for it.
If you want LM14 features, then buy an
LM14A. Not having "preset dim" is one of the
reasons the LM465 is 20 bucks cheaper than
the LM14A.

[roger1818]

Dave:  The main cause of the extra cost for
the LM14A is the 2-way interface, which
requires additional hardware and software.
Besides, I am not asking for Preset Dim
(that would require adding support of
extended commands).  What I am asking for
is changing the off state to be the same as
0% brightness.  That way you can ramp it up
to the desired brightness using the
brighten command instead of having to go to
100% and then dim it.

[dave w]

Roger H: I think the problem is the LM 465
is too dumb to do that. 0% brightness keeps
the triac firing at some very low level. You
would still have to have a triac OFF state
to satisfy any number of safety regulations.
Now you have two "light bulb dark"
states,"OFF" and "0%"  so there would have
to be some memory in the LM465. Which means
hardware change.
I use AHP's relative DIM and BRIGHTEN
commands to create a bathroom light which
brightens from 0% rather than come on at
full brightness. Wouldn't that work for you.?

[roger1818]

Dave:  I just had a look at the schematic
for the LM465 and pin 6 of the PIC controls
both the brightness and ON/OFF state of the
triac so the 0% level and OFF states must
defined in firmware not hardware.  Making
the 0% level turn off the triac would
satisfy the safety regulations.  I am not
sure why you think reducing the number
of "light bulb dark" states from 2 to 1
would require memory that doesn’t currently
exist?

If you read my original post, I did mention
your method of dimming to 0% instead of
turning it off, but it would be nice if you
didn’t have to do this.

[dave w]

H-m-m-m. Well, here is what I was thinking.
The 0% (actually it isn't "0" but some value
below the bulb filament being incandescent)
and the triac OFF state, are two different
states. What I called "0%" actually requires
the triac to be constantly fired at some low
current angle. This requires a continous
60Hz pulse train out of pin 6. In order for
the module to "remember" what that firing
angle is, AND still allow the triac to quit
conducting thus totally interupt current to
the bulb, then the chip would need some
memory to remember the phase angle it must
gate the triac at, to start the bulb out dim
and then brighten it.

A side question, are you sure the chip in
the simple lamp module and wall switch is
actually a PIC?

Thanks