基于ESP8266门禁系统显示器代码

以下是基于ESP8266门禁系统显示器的代码示例：

#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <ESP8266HTTPClient.h>
#include <LiquidCrystal_I2C.h>

// Replace with your network credentials
const char* ssid     = "Your_SSID";
const char* password = "Your_PASSWORD";

// Set web server port number to 80
ESP8266WebServer server(80);

// Set LCD pins
LiquidCrystal_I2C lcd(0x3F, 16, 2); // Set the LCD I2C address and dimensions

String serverUrl = "http://your-server-url.com/"; // Replace with your server URL

void setup() {
  // Initialize Serial Monitor
  Serial.begin(115200);

  // Connect to Wi-Fi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");

  // Start LCD
  lcd.init();                      // Initialize the LCD
  lcd.backlight();                 // Turn on the backlight
  lcd.setCursor(0, 0);             // Set the cursor to the first row
  lcd.print("Connected to WiFi");  // Display message on LCD
}

void loop() {
  // Handle client requests
  server.handleClient();

  // Check if there is a new message from the server
  HTTPClient http;
  http.begin(serverUrl);    // Specify the URL
  int httpCode = http.GET();  // Make the request
  if (httpCode == 200) {       // Check if the response is successful
    String message = http.getString();  // Get the message
    Serial.println(message);             // Print the message to Serial Monitor
    lcd.clear();                         // Clear the LCD
    lcd.setCursor(0, 0);                // Set the cursor to the first row
    lcd.print(message);                 // Display the message on the LCD
  }
  http.end();  // Close the connection
}

这个示例代码连接到Wi-Fi网络，然后初始化LCD显示器。它会从服务器获取消息并在LCD上显示。你需要把`Your_SSID`和`Your_PASSWORD`替换成你的Wi-Fi网络凭据，把`your-server-url.com`替换成你的服务器URL。