Программирование RGB ленты на Arduino

#include <time.h>
int a1,a2,a3,c1,c2,c3,l;
void setup() {
  Serial.begin(9600);
  // put your setup code here, to run once:
 srand(time(NULL));
  a1=rand() %255+1;
  analogWrite(3, a1);
  a2=rand() %255+1;
  analogWrite(5, a2);
  a3=rand() %255+1;
  analogWrite(6, a3);
  
c1=1;
c2=0;
c3=1;
  
 
}
 
void loop() {
  // put your main code here, to run repeatedly:
//Serial.print("a1=");
Serial.print(a1);
//Serial.print(" a2=");
Serial.print(" ");
Serial.print(a2);
//Serial.print(" a3=");
Serial.print(" ");
Serial.print(a3);
Serial.print(" ");
Serial.print(c1);
Serial.print("\n");
delay(10);
  
 
  if(0<=a1&&a1<=5)
  {c1=1;}
  else if(250<=a1&&a1<=255)
  {c1=0;}
   if(0<=a2&&a2<=5)
  {c2=1;}
  else if(250<=a2&&a2<=255)
  {c2=0;}
   if(0<=a3&&a3<=5)
  {c3=1;}
  else if(250<=a3&&a3<=255)
  {c3=0;}
  analogWrite(3, a1);
  if(c1==1)
  {
    l=rand() % 5 +1;
    a1+=l;;
  }
  else
  {
    l=rand() % 5 +1;
    a1-=l;;
  }
  delay(25);
  analogWrite(5, a2);
  if(c2==1)
  {l=rand() % 5 +1;
    a2+=l;;
  }
  else
  {l=rand() % 5 +1;
    a2-=l;;
  }
  delay(2);
   analogWrite(6, a3);
  if(c3==1)
  {l=rand() % 5 +1;
    a3+=l;;
  }
  else
  {l=rand() % 5 +1;
    a3-=l;;
  }
  delay(2);
//delay (500);
 
}

a1=rand() %256;