Controlling built-in WS2812B RGB LED on Cucumber board.

ESP32S2Neopixel.ino

/*
  Tutorial: Program ESP32-S2 Using Arduino IDE (Unofficial)
  Board: ESP32S2 (Cucumber from Gravitech)
  
  External libraries:
  - Adafruit NeoPixel V1.5.0 (Manager)
 */

#include <Adafruit_NeoPixel.h>
#define PIN 18
#define NUMPIXELS 1
Adafruit_NeoPixel pixels(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

enum {NONE, RED, GREEN, BLUE};
int ledColor = NONE;

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

void loop()
{
  switch (ledColor) {
    case NONE:
      pixels.setPixelColor(0, pixels.Color(0, 0, 0));
      pixels.show();
      break;

    case RED:
      pixels.setPixelColor(0, pixels.Color(20, 0, 0));
      pixels.show();
      break;

    case GREEN:
      pixels.setPixelColor(0, pixels.Color(0, 20, 0));
      pixels.show();
      break;

    case BLUE:
      pixels.setPixelColor(0, pixels.Color(0, 0, 20));
      pixels.show();
      break;

    default:
      break;
  }

  ledColor++;
  if (ledColor == 4) {
    ledColor = NONE;
  }

  delay(1000);
}