FastLED test for ESP32 APA102 based on https://github.com/FastLED/FastLED/wiki/Basic-usage#moving-an-led

sketch_dec03a.ino

#include "FastLED.h"
#define DATA_PIN    16
#define CLK_PIN     17
#define LED_TYPE    APA102
#define COLOR_ORDER BGR // RGB, BGR
#define NUM_LEDS    64

#define BRIGHTNESS  30

CRGB leds[NUM_LEDS];

void setup() {
  Serial.begin(115200);
  FastLED.addLeds<LED_TYPE, DATA_PIN, CLK_PIN, COLOR_ORDER, DATA_RATE_MHZ(1)>(leds, NUM_LEDS);

  FastLED.setBrightness(BRIGHTNESS);
  fill_solid(leds, NUM_LEDS, CRGB::Blue);
  FastLED.show();
}

void loop() {
  for(int dot = 0; dot < NUM_LEDS; dot++) {
    Serial.print("x"); // Print an "x" so we know it's running...
    leds[dot] = CRGB::Blue;
    FastLED.show();
    // clear this led for the next time around the loop
    leds[dot] = CRGB::Black;
    delay(30);
  }
}