#include <Adafruit_NeoPixel.h>

//---------------------------------------------------------------------
#define PIN_ADC_POTENTIOMETER  A0

#define PIN_AUSGABE  9
#define ANZAHL_LED  30

Adafruit_NeoPixel pixels = Adafruit_NeoPixel(ANZAHL_LED, PIN_AUSGABE, NEO_GRB + NEO_KHZ800);

//---------------------------------------------------------------------
void setup()
{
  pixels.begin();
}

//---------------------------------------------------------------------
void loop()
{
  //---
  int adc_potentiometer = analogRead(PIN_ADC_POTENTIOMETER);

  int tg = map(adc_potentiometer, 0, 1023, 0, 255);

  //---
  for(int x=0; x <=ANZAHL_LED; x++) {
    pixels.setPixelColor(x, tg, tg, tg);
  }

  pixels.show();

  delay(100);
}