Controlling Ac lighint

[gadget-evilusions]

I am looking to do some weird stuff with incandescent bulbs. I know if I want to flciker, I could probably use an rc-4 and turn them on and off and random times, but what I am looking for is the ability to dim. Similar to what you would get with pwm'ing leds. Is there anything that I could interface with a prop-1 to do such a thing. (I really don't want to contol a rotary dimmer switch with a servo, which I know is one option.)

[livinlowe]

Dimming lights is possible, but a commercial solution that is cheaply available for the prop-1 or 2 isn't around. Yet. I have a feeling (think I read it) people are working on it though. Check out the Parallax website forums and search for this subject. Someone posted a homebrew circuit that does the job. :D

[gadget-evilusions]

Unfortunately most of the talk on the parallax forums are over my head. I have to pay people to design and build my circuit boards.

[JonnyMac]

We're listening.  As part of my book project for Parallax I'm doing some fader circuits and in the process created this prototype for what we will call the FC-4 (four-channel fader):



It works like the RC-4, accepting serial commands at 2400 (Prop-1) or 38,400 (Prop-2) baud -- there are no manual controls; it requires an external host.

I just got it working the other day and this is a PROTOTYPE only; moving to production will take a couple months (probably mid summer).  Stop by our booth at HauntCon and we'll show you how it works.

PS: Sorry for the fuzzy photo, I snapped it in a hurry to include it in this post.

[clinefx1]

Awesome.

[JonnyMac]

Thanks, Chris.  Here's the command set that FC-4 currently supports (after the "!FC4" header and board address):

"V" - returns version (3 bytes)
"G" - returns brightness levels (0 - 255) of all channels (4 bytes)
"L" - set the level of an individual channel (pass channel and level; two bytes)
"S" - set the level of all channels (pass levels; four bytes)
"P" - preset all channels to a level (pass the level; one byte)
"A" - sell all channels to full bright
"C" - cross fade between two channels (pass channel A, channel B, step timing [xfade takes 256 steps]; three bytes)
"D" - digital control of channels (pass nib with on/off status bits; one byte)
"X" - reset all channels to full off

I've tested with the Prop-1 and Prop-2 -- everything seems to be working as we want.  The only thing I may do is add a linearization table to the code as triac switching as in these kinds of dimmers is distinctly non-linear.

[livinlowe]

Jon-
I hope you guys like making money and being EXTREMELY busy! ;D This is BAD! I cannot wait to get one! Good Job!!

P.S. ( I just knew you guys are good!)

[gadget-evilusions]

That is awesome. I couldn't find anything like this and was about to have one designed for me. I guess I don't have too now. Thanks for everything you guys do! I will definelty stop by your booth at Hauntcon, I think my booth is in the same aisle.