无法在setup()中使用带有ESP8266WiFi.h库和Arduino IDE的HiLetgo ESP8266进行串行打印

#include <ESP8266WiFi.h>
#include <Serial.h>

bool wifiConnected = false;

void setup() {
  // 初始化串行通信
  Serial.begin(9600);

  // 连接WiFi网络
  WiFi.begin("your_SSID", "your_password");

  // 等待WiFi连接成功
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }

  // WiFi连接成功
  wifiConnected = true;
  Serial.println("WiFi connected!");
}

void loop() {
  if (wifiConnected) {
    // 在这里进行串行打印操作
    Serial.println("Hello, world!");
    delay(1000);
  }
}