Simpe RGB Controller again.

[donniedj]

Well simple as a PIC controller can be. You all seen those etched glass blocks with 3d images in the center. These are also equiped with short lighted bases showing semi random RGB lights sequences.

Well I bought a couple but came to realize that the ones I have only work with 3 Alkaline AA batteries. I do not use or by Alkaline for the obvious reason $$$ so now I am stuck with these lighted bases that do not work from 3 NIMH batteries. I made an RGB controller a while back and I know that it runs great from from 3-5v.

I ripped out the original RGB board that had 3 seperate leds and simple patterns and replaced my own PIC single RGB led controller. Now I can easily make any color, any fade, any color gradients, and any pattern with my own code. By the way my board runs longer, runs brighter, and is 1/2 the size of the original.

Excerpts of the code:
'--DORGB(REG,GREEN,BLUE,TIME)
DORGB 249,249,249, 20
DORGB 0,0,0, 5
DORGB 249,249,249, 20
DORGB 0,0,0, 5
DORGB 249,249,249, 100
DORGB 0,0,0, 5
DORGB 150,125,75,100
DORGB 50,125,175,100

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[Mike - K8LH]

Bravo! Nicely done!

May I ask which RGB LED you're using (Manufacturer, Part Number, Source), please?

Mike

 

[blueroomelectronics]

No current limiting resistors? nicely done post.

 

[donniedj]

The LED is common cathode and clear lens, for thats all I know. I bought a lot on feebay a long time ago. I have to sand or paint the epoxy for good color diffustion. This same board also works good on 1W luxen. Though the PIC will not deliver 1W its still bright as hell.

So you noticed no resistors. I never use them in my LED boards. I have many other 8 and 16 led chasers on small footprint boards due to using only chip and led and none have resistors because I PWM real good. Duty cycle is always very low. Even when LEDs look constant on, its not.

In this instance, by activated each RGB channel individually, I can get away with not using a biase resistor, no need for current control. PICs have a lowest load dominator behavior you all should know about by now. If 3 I/O lines are all turned on but on the the lines is a 1.8V led then remaining 2 or port will spit out just above 1.8V which will not illuminate other leds requiring > 3.0V. Activated each RGB channel overcomes that lowest load effect.

 

[theinfamousbob]

You could fit an SMD resistor on the cathode...I like the board though.