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Arduino Serial to LED communication

 * ShiftPWM blocking RGB fades example, (c) Elco Jacobs, updated August
 * ShiftPWM blocking RGB fades example. This example uses simple delay
loops to create fades.
 * If you want to change the fading mode based on inputs (sensors,
buttons, serial), use the non-blocking example as a starting point.
 * Please go to for documentation, fuction
reference and schematics.
 * If you want to use ShiftPWM with LED strips or high power LED's,
visit the shop for boards.
// Clock and data pins are pins from the hardware SPI, you cannot choose them yourself if you use the hardware SPI.
// Data pin is MOSI (Uno and earlier: 11, Leonardo: ICSP 4, Mega: 51, Teensy 2.0: 2, Teensy 2.0++: 22)
// Clock pin is SCK (Uno and earlier: 13, Leonardo: ICSP 3, Mega: 52, Teensy 2.0: 1, Teensy 2.0++: 21)
// You can choose the latch pin yourself. 
const int ShiftPWM_latchPin=8;
// If your LED's turn on if the pin is low, set this to true, otherwise set it to false.
const bool ShiftPWM_invertOutputs = false;
// You can enable the option below to shift the PWM phase of each shift register by 8 compared to the previous.
// This will slightly increase the interrupt load, but will prevent all PWM signals from becoming high at the same time.
// This will be a bit easier on your power supply, because the current peaks are distributed.
const bool ShiftPWM_balanceLoad = false;
#include <ShiftPWM.h>   // include ShiftPWM.h after setting the pins!
unsigned char maxBrightness = 128;
unsigned char pwmFrequency = 75;
int numRegisters = 3;
int numRGBleds = 4;
void setup(){
  // Sets the number of 8-bit registers that are used.
  // SetPinGrouping allows flexibility in LED setup.
  // If your LED's are connected like this: RRRRGGGGBBBBRRRRGGGGBBBB, use SetPinGrouping(4).
  ShiftPWM.SetPinGrouping(1); //This is the default, but I added here to demonstrate how to use the function
void loop()
  /*for(int led=0;led<numRGBleds;led++){ // loop over all LED's
  for(int intensity=0;intensity<255;intensity++){ // loop over all LED's
    ShiftPWM.SetRGBW(led, intensity, 0, 0, 0);
   for(int intensity=255;intensity>0;intensity--){ // loop over all LED's
    ShiftPWM.SetRGBW(led, intensity, 0, 0, 0);
   while (Serial.available() > 0) {
     int led = Serial.parseInt();
     int red = Serial.parseInt();
     int green = Serial.parseInt();
     int blue = Serial.parseInt();
     //int white = Serial.parseInt();
     if ( == '\n') {
       ShiftPWM.SetRGBW(led, red, green, blue, 0);
serial-parse-led.txt · Last modified: 2014/09/03 19:42 by zoza