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Products For this project I'll describe how to hook up 10 of our 20mm RGB modules and control them any way you like using an Arduino Duemilanove. You can use any Arduino or compatible board, but if you want to run a lot of LEDs you'll need one with the 328 controller - it's twice as fast as the old ones and has 2k of memory rather than 1k. Having said that, any Arduino will easily run a few hundred LEDs. Connect the blue wire to GND and the red wire to 5V on the Arduino. The LEDs need 5 Volts to run. We'll take that straight off the Arduino since we're only using 10 LEDs here.  Each LED can pull a maximum of 60mA at full brightness white light, so don't go running it over warp 9 for too long. Connect the yellow wire to 11 (Data) and the green wire to 12 (Clock) You can change which pins you'd like to use in the code. The code uses the Arduino TimerOne library: http://www.arduino.cc/playground/Code/Timer1 Download as per the instructions. Now, start a new Arduino Sketch and paste in the example code below. Compile. Upload. #include <TimerOne.h> //Example to control 10 RGB LED Modules. //Bliptronics.com //Ben Moyes 2009 //Use this as you wish, but please give credit, or at least buy some of my LEDs! // // Choose which 2 pins you will use for output. // Can be any valid output pins. int clockPin = 12; int dataPin = 11; byte SendMode=0; // Used in interrupt 0=start,1=header,2=data,3=data done byte BitCount=0; // Used in interrupt byte LedIndex=0; // Used in interrupt - Which LED we are sending. byte BlankCounter=0; //Used in interrupt. unsigned int BitMask; //Used in interrupt. //Holds the 15 bit RGB values for each LED. //You'll need one for each LED, we're using 10 LEDs here. //Note you've only got limited memory on the Arduino, so you can only control //Several hundred LEDs on a normal arduino. Double that on a Duemilanove. unsigned int Display[10]; void setup() { byte Counter; pinMode(clockPin, OUTPUT); pinMode(dataPin, OUTPUT); // Turn all LEDs off. for(Counter=0;Counter < 10; Counter++) Display[Counter]=Color(Counter,0,31-Counter); show(); Timer1.initialize(25); // initialize timer1, 25 microseconds refresh rate. Timer1.attachInterrupt(LedOut); // attaches callback() as a timer overflow interrupt } //Interrupt routine. //Frequency was set in setup(). Called once for every bit of data sent //In your code, set global Sendmode to 0 to re-send the data to the pixels //Otherwise it will just send clocks. void LedOut() { switch(SendMode) { case 3: //Done..just send clocks with zero data digitalWrite(dataPin, 0); digitalWrite(clockPin, HIGH); digitalWrite(clockPin, LOW); break; case 2: //Sending Data if (BitCount==0) //First bit is always 1 { digitalWrite(dataPin, 1); BitMask=0x8000;//Init bit mask } else if(BitMask & Display[LedIndex]) //If not the first bit then output the next bits (Starting with MSB bit 15 down.) digitalWrite(dataPin, 1); else digitalWrite(dataPin, 0); BitMask>>=1; BitCount++; if(BitCount == 16) //Last bit? { LedIndex++; //Move to next LED if (LedIndex < 10) //Still more leds to go or are we done? { BitCount=0; //Start from the fist bit of the next LED } else SendMode=3; //No more LEDs to go, we are done! } // Clock out data. digitalWrite(clockPin, HIGH); digitalWrite(clockPin, LOW); break; case 1: //Header if (BitCount < 32) { digitalWrite(dataPin, 0); BitCount++; if(BitCount==32) { SendMode++; //If this was the last bit of header then move on to data. LedIndex=0; BitCount=0; } } digitalWrite(clockPin, HIGH); digitalWrite(clockPin, LOW); break; case 0: //Start if(!BlankCounter) //AS SOON AS CURRENT pwm IS DONE. BlankCounter { BitCount=0; LedIndex=0; SendMode=1; } digitalWrite(clockPin, HIGH); digitalWrite(clockPin, LOW); break; } //Keep track of where the LEDs are at in their pwm cycle. BlankCounter++; } void show() { // The interrupt routine will see this as re-send LED color data. SendMode = 0; } // Create a 15 bit color value from R,G,B unsigned int Color(byte r, byte g, byte b) { //Take the lowest 5 bits of each value and append them end to end return( ((unsigned int)g & 0x1F )<<10 | ((unsigned int)b & 0x1F)<<5 | (unsigned int)r & 0x1F); } // Show a colour bar going up from 0 to 9 void ColorUp( unsigned int ColourToUse) { byte Counter; for(Counter=0;Counter < 10; Counter++) { Display[Counter]=ColourToUse; show(); delay(25); } } // Show a colour bar going down from 9 to 0 void ColorDown( unsigned int ColourToUse) { byte Counter; for(Counter=10;Counter > 0; Counter--) { Display[Counter-1]=ColourToUse; show(); delay(25); } } //Input a value 0 to 127 to get a color value. //The colours are a transition r - g -b - back to r unsigned int Wheel(byte WheelPos) { byte r,g,b; switch(WheelPos >> 5) { case 0: r=31- WheelPos % 32; //Red down g=WheelPos % 32; // Green up b=0; //blue off break; case 1: g=31- WheelPos % 32; //green down b=WheelPos % 32; //blue up r=0; //red off break; case 2: b=31- WheelPos % 32; //blue down r=WheelPos % 32; //red up g=0; //green off break; } return(Color(r,g,b)); } void loop() { unsigned int Counter, Counter2, Counter3; // Lets show some demo patterns. // Just change Display array, then set SendMode to 0 //Spin LED with colour changing for(Counter=0;Counter < 10;Counter++) { for(Counter2=0; Counter2 < 10 ; Counter2++) { Display[Counter2] = Wheel(Counter * 10 + Counter2); show(); delay(25); Display[Counter2] = Color(0,0,0) ; show(); } } //Scrolling Rainbow Effect for(Counter=0; Counter < 200 ; Counter++) { Counter3=Counter * 1; for(Counter2=0; Counter2 < 10; Counter2++) { Display[Counter2] = Wheel(Counter3%95); //There's only 96 colors in this pallette. Counter3+=10; } show(); delay(25); } //Color wipes. for(Counter=0;Counter < 2;Counter++) { ColorUp(Color(random(0,32),random(0,32),random(0,32))); delay(500); ColorDown(Color(random(0,32),random(0,32),random(0,32))); delay(500); } } Voila! You now can sit back and watch the blinkenlights. Your Cart Cart is empty Your currency Australian Dollars British Pounds Euro Japan Yen South Korea Won US Dollars Information About us
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