Sample code for remote control of Arduino and WS2811 LED strip

ws2811_led_client.py

#!/usr/bin/python

import socket
from time import sleep
from random import randint

# addressing information of target
IPADDR = '2.0.0.20'
PORTNUM = 6000

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, 0)
s.connect((IPADDR, PORTNUM))
s.send(bytes(2) + "\n")
s.close()

def f7(seq):
    seen = set()
    seen_add = seen.add
    return [ x for x in seq if x not in seen and not seen_add(x)]


try:
  for i in range(30000):
      s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, 0)
      s.connect((IPADDR, PORTNUM))
      cmd = chr(1) + chr(randint(1,154)) + chr(randint(1,154)) + chr(randint(1,154))
      cmdlist = []
      for j in range(200):
        #cmd = cmd + chr(randint(1,240))
        #cmd = cmd + chr(j)
        cmdlist.append(randint(1,240))
      print cmdlist
      for j in sorted(f7(cmdlist)):
        cmd = cmd + chr(j)
      #print cmd
      s.send(cmd)
      s.close()
      #sleep(0.61)
      #print i
except:
      s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, 0)
      s.connect((IPADDR, PORTNUM))
      s.send(chr(2))
      s.close()

ws2811_led_server.ino

#include <FastSPI_LED.h>
#include <SPI.h>  
#include <Ethernet.h>
#include <EthernetUdp.h>


#define NUM_LEDS 240

uint8_t mac          [6] = {   1,   2,   3,   0,   0,  20}; // the mac address of node
uint8_t localIp      [4] = {   2,   0,   0,  20};  
unsigned int localPort = 6000; 
// Sometimes chipsets wire in a backwards sort of way
struct CRGB { unsigned char b; unsigned char r; unsigned char g; };
// struct CRGB { unsigned char r; unsigned char g; unsigned char b; };
struct CRGB *leds;

#define PIN 4

//const int MAX_BUFFER_UDP = 1650;
//volatile uint8_t packetBuffer [MAX_BUFFER_UDP];
//unsigned char packetBuffer[UDP_TX_PACKET_MAX_SIZE];
unsigned char packetBuffer[1600];

EthernetUDP Udp;

int freeRam () {
  extern int __heap_start, *__brkval; 
  int v; 
  return (int) &v - (__brkval == 0 ? (int) &__heap_start : (int) __brkval); 
}

void setup()
{
  Serial.begin(115200);
  Ethernet.begin(mac, localIp); 
  Udp.begin(localPort);
  
  FastSPI_LED.setLeds(NUM_LEDS);
  FastSPI_LED.setChipset(CFastSPI_LED::SPI_WS2811);

  FastSPI_LED.setPin(PIN);
  
  FastSPI_LED.init();
  FastSPI_LED.start();

  leds = (struct CRGB*)FastSPI_LED.getRGBData(); 
}

void loop() { 
  
  long packetSize = Udp.parsePacket();
  if( Udp.available()  ) 
    handle_packet(packetSize);
  //Serial.print("freeMemory()=");
  //Serial.println(freeRam());   
}

void handle_packet(long packetSize) {
  
//  Udp.read(packetBuffer,UDP_TX_PACKET_MAX_SIZE); 
  Udp.read(packetBuffer,1600); 
  //Serial.println("Contents:");
  //Serial.println(packetBuffer);

  //packetBuffer[packetSize+1] = '\0';
  int offset = 0;
  if (packetBuffer[offset] == 1) {
     offset++;
     int r = packetBuffer[offset]; offset++;
     int g = packetBuffer[offset]; offset++;
     int b = packetBuffer[offset]; offset++;
     if (r > 255) r=255;
     if (g > 255) g=255;
     if (b > 255) b=255;
     char rgb[20];
     sprintf(rgb, "RGB %d %d %d", r, g, b);
     Serial.println(rgb);
     //Serial.println("RGB:" + itoa(r) + itoa(g) + itoa(b));
     memset(leds, 0, NUM_LEDS * 3);
     int lastl = 0;
     for (int i = offset; i < (packetSize-1); i++) {
       int l = packetBuffer[i]; 
       //Serial.print(l); Serial.print(",");
       if (l > lastl + 1) {
         for (int j=lastl; j < l; j++) {
           leds[l].r = 0;
           leds[l].g = 0;
           leds[l].b = 0;
         }
       }
       leds[l].r = r;
       leds[l].g = g;
       leds[l].b = b;
     }
     Serial.println("");
  } else if (int(packetBuffer[offset]) ==  2) {
    memset(leds, 0, NUM_LEDS * 3);
    //Serial.println("ALL OFF");
  } else {
    Serial.println(packetBuffer[offset]);
  }
  noInterrupts();
  FastSPI_LED.show();
  delay(10);
  interrupts();
  //Serial.println("show\n");
  
}