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RGB Led PWM controller

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computer

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Hi,

I was wondering if some of you can help me.

I want something that will control 4 RGB leds (through transistors) and PWM them from a PIC chip. I need schematics, chip and code information as I have no knowledge on this, I may also be willing to get someone to program one of these chips for me and then pop it in the post if I pay them for it/the cost/etc.

So,
I need 3 outputs, one for red, green and blue. I need to be able to connect it to some rotary encoders, which I need to buy (I am looking at some ones from Rapid, for £4 which have a push output as well).

I need it so that 3 rotary encoders will turn to control the red, green and blue respectively, and when you push one of the rotary encoders (1-3) it will save their values in its memory, so they can be 'triggered' from 3 push buttons (so I can have 3 presets). I also need an on/off switch, but I think I can manage that ;).

Hope someone can help me, I'm in the UK btw,
computer

PS: I think I need a really idiots guide/lots of help here! I don't have any PIC stuff, no programmers, chips or anything, just some RGB leds and lots of other electronics.
PPS: This needs to run from a LV 12v transformer which is regulated.
 
I am using software control to dim 3 led (pic basic), if u are interested juz pm me:>


cheers
 
RGB-controller using PIC 12C508

Hi,
just found this nice forum.
I have programmed a PIC 12C508 to do the following 'tricks':
- automatic colorfading, speed adjustable in 256 steps
- random colorchanging, speed adjustable in 256 steps
- strobe with automatic colorfading, strobe frequency adjustable in 256 steps
- strobe with random colorchanging, strobe frequency adjustable in 256 steps
- fire simulation
- intensitiy of R (G,B)-channel adjustable in 256 steps (each) to mix static colors
- white light dimmer (256 steps)with same intensity for all 3 channels
- 3 PWM channels (R,G,B) @~80Hz
- operated via 6 buttons
forgot something:
- 'freeze' function to stop actual running FX
- 'on/off' function to switch LEDs on/off. FX is stopped when off.
At the moment i am planning a kit to make assembly easy even for 'newbies'.
Is that what You are looking for?
regards
joachim
 
Hi again,

are Your RGB-LEDs common anode or cathode, or a single LED for each basic color?

joachim
 
well I have some types I want to use as an indicator which is 3 positives (cant remember which is anode/cathode!) and a negative, and my main LEDs I want to use are separate ones...

so do you run all of this including the 'dimming'/level setting from the 6 buttons like a + and - setup?

also does the chip need any external components like a crystal, capacitor/etc to run, if so it might good if you'd be able to slip one in the bag so to say if the price is right...
 
A picture says more than 1000 words, so here is a basic schematic (a bit oversized, sorry):
 

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To drive common cathode LEDs a 'high side driver' is needed, what is a little more complicated if V+ is higher than 5V. I'll post an addendum soon.

Because i don't know the conventions of this forum concerning 'buy,sell,trade' it might be better to mail.
 
@RGBrainbow.. I'm trying to produce a very similar system, but I need it running at a pretty high speed. I plan to swing mine around, but need the PWM signals to be sufficiently fast that you can't see the pulses seperating out. How fast can your code / PIC run?
 
@G33K: It's an internally clocked 12c508. The PWM frequency is about 75Hz. Enough to avoid flickering as long as the LEDs don't move. For a propeller-clock or other moving LED stuff You'll need PWM-frequencies of 10kHz or higher. I don't think that this can be done in software without making too much compromises. Three (for RGB-stuff) fast hardware PWMs are needed or at least one multiplexed into R,G,B channel. Unfortunately Microchip still stints with PWM channels in the midrange series....
regards
joachim
 
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