Re: Controlling Holiday Lights

[johnh@xxxxxxxxx (John Haskey)]

In article <slrnejfnul.uc9.ZsdbUse1+noZs_0610@xxxxxxxxxxxxxxx>,
sylvan butler  <ZsdbUse1+noZs_0610@xxxxxxxxxxxxxxxxxxxxx> wrote:
>On Wed, 18 Oct 2006 23:35:59 +0000 (UTC), John Haskey <johnh@xxxxxxxxx> wrote:
>> In article <slrnejam1g.thm.ZsdbUse1+noZs_0610@xxxxxxxxxxxxxxx>,
>> sylvan butler  <ZsdbUse1+noZs_0610@xxxxxxxxxxxxxxxxxxxxx> wrote:
>>>
>>>Anybody have a source for cheap PCI parallel port cards (e.g. four
>>>parallel ports on one card)?
>>
>> Why not use MIDI?
>
>SsssssssLlllllllOoooooooWwwwwwwww

Given the solid state relay you reference in the previous post you could
send the MIDI command to turn the light on and off four times (worst case)
in the time it would take the relay to turn on.

>Granted, MIDI is probably 10x the speed (in theory) of X10, but I
>haven't seen a complete solution to know what is achievable.  And that
>still means only about 10 cycles per second (Hertz or Hz), which still
>limits you to only basic on/off effects.  (Compare to 50-60Hz for a
>zero-crossing A.C. relay or way over 1000Hz for a PC parallel port.)

I agree that the parallel port is much faster but how fast is fast
enough?  Your relay is going to take ~8ms to turn on.  An incandescent
bulb can take at least 25ms to reach full brightness (often more).
It depends on how many relays you are going to control and that's
pretty limited unless you multiplex your parallel port.

Do whatever works.  I think MIDI may be fine in many cases.  And it'd
be easy to program given the free software that is available.

							---john.