Control/Dimming RF-controlled RGB LED lamp

Letho

Member
Joined
Nov 9, 2011
Location
South Africa
Hello everybody!

I am humbly asking for guidance in my project;the project requires me to design a mini-lighting console to control a multi-colored LED light. This light must be dimmable and must be RF controlled. I am of cause thinking of having 3 RGB linear pots (faders),each giving out the amount of either RED,GREEN or BLUE on the output side. I am still not sure whether i can use the three different LEDs or use the multi-colored LED,but either way,the light emitted will be covered with a white globe in order to perfectly realise the effective output while demonstrating this.
It therefore requires me to write the code and build the hardware.

Thank you in advance!
 

JChenault

Well-Known Member
Joined
Jan 5, 2009
Location
seattle, wa USA
What is the goal of this project? Are you trying to learn how to write code, build a fixture, understand RF controls or what?

Virtually all of the things you are trying to build are available off the shelf. Is this a school project and if so what are you trying to learn?
 

Letho

Member
Joined
Nov 9, 2011
Location
South Africa
What is the goal of this project? Are you trying to learn how to write code, build a fixture, understand RF controls or what?

Virtually all of the things you are trying to build are available off the shelf. Is this a school project and if so what are you trying to learn?
This is a school project towards a B-tech qualification in Electrical and electronics engineering,and i basically have to bring everything I have learned together to come up with a working model. The major concern here is the controller that i have to design,yes i'm thinking of using an off the shelf RF module that understands DMX. and even the slave that will execute what it has been commanded but i think there'll be modifications here and there in order to suit the project title..
Thank you
 

n1ist

Well-Known Member
Joined
Jun 30, 2005
Location
Malden MA
I don't know of any off-the-shelf wireless modules that speak DMX (talking about PCB-mountable radios here, not complete packaged units); most hit a bandwidth limit. One of the guys over at DIYC has managed to push a full universe over Microchip's 802.15.4 module with his own protocol.

That being said, I would make two units - a DMX or slide pot to wireless bridge that sends a small number of channels (3 or 4 per fixture), and the fixture itself. XBEEs make good radios for this, as does Microchip and some of the other procesor vendors.

For the fixture, I would probably use RGB LEDs to get around issues with color mixing; they mix better without color fringes due to the close spacing of the LED dies. You may need more than one to get even illumination.

So for the sender, it would be either three pots or an RS485 receiver, a micro, and a radio. For the receiver, a radio, micro, drivers, and the LEDs. No real load on the micro here; one needs either a UART or some A/D inputs, the other a UART and 3 PWM channels. I'd go with an ATMega8 myself, but a PIC or MSP430 would also work well; use whichever you are familiar with.

Feel free to PM or email me if you have more questions.
/mike