单片机课堂思考题-如何用手机控制单片机IO口-如点亮一个LED

主要考察学生思路，常见现象是直接网上查找然后开始刷刷看并写到本子上。

很难了，思考-检索-推荐，在互联网算法的投喂下，大部分已经丧失了独立思考的能力了。

第一步，需要使手机和单片机建立连接，通常手机不用串口连接外设，一般而言适用无线wifi和蓝牙。

第二步，才是构思程序架构，比如控制哪些IO口，如何配置wifi和蓝牙等。

第三步，在设计好程序流程图之后，依据具体芯片特色进行程序设计。

简言之，连通性和控制程序。

参考程序如下：

IO口可以更换为2、4等，依据具体情况适当调整。

      #include <WiFi.h>
      const char* ssid     = "yourssid";
      const char* password = "yourpasswd";
      WiFiServer server(80);
      void setup()
      {
          Serial.begin(115200);
         pinMode(5, OUTPUT);      // set the LED pin mode
         delay(10);
         // We start by connecting to a WiFi network
          Serial.println();
          Serial.println();
          Serial.print("Connecting to ");
          Serial.println(ssid);
          WiFi.begin(ssid, password);
         while (WiFi.status() != WL_CONNECTED) {
             delay(500);
              Serial.print(".");
          }
          Serial.println("");
          Serial.println("WiFi connected.");
          Serial.println("IP address: ");
          Serial.println(WiFi.localIP());
          server.begin();
      }
      int value = 0;
      void loop(){
       WiFiClient client = server.available();   // listen for incoming clients
       if (client) {                             // if you get a client,
          Serial.println("New Client.");           // print a message out the serial port
          String currentLine = "";                // make a String to hold incoming data from the client
         while (client.connected()) {            // loop while the client's connected
           if (client.available()) {             // if there's bytes to read from the client,
             char c = client.read();             // read a byte, then
              Serial.write(c);                    // print it out the serial monitor
             if (c == '\n') {                    // if the byte is a newline character
               // if the current line is blank, you got two newline characters in a row.
               // that's the end of the client HTTP request, so send a response:
               if (currentLine.length() == 0) {
                 // HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
                 // and a content-type so the client knows what's coming, then a blank line:
                  client.println("HTTP/1.1 200 OK");
                  client.println("Content-type:text/html");
                  client.println();
                 // the content of the HTTP response follows the header:
                  client.print("Click <a href=\"/H\">here</a> to turn the LED on pin 5 on.<br>");
                  client.print("Click <a href=\"/L\">here</a> to turn the LED on pin 5 off.<br>");
                 // The HTTP response ends with another blank line:
                  client.println();
                 // break out of the while loop:
                 break;
                } else {    // if you got a newline, then clear currentLine:
                  currentLine = "";
                }
              } else if (c != '\r') {  // if you got anything else but a carriage return character,
                currentLine += c;      // add it to the end of the currentLine
              }
             // Check to see if the client request was "GET /H" or "GET /L":
             if (currentLine.endsWith("GET /H")) {
               digitalWrite(5, HIGH);               // GET /H turns the LED on
              }
             if (currentLine.endsWith("GET /L")) {
               digitalWrite(5, LOW);                // GET /L turns the LED off
              }
            }
          }
         // close the connection:
          client.stop();
          Serial.println("Client Disconnected.");
        }
      }
  
 

连接上WiFi之后，一定要注意查看串口获取单片机wifi的ip地址然后，适用手机或者电脑的浏览器登陆，就可以控制灯亮灭了。

也就是控制IO口输出高低电平。

文章来源: zhangrelay.blog.csdn.net，作者：zhangrelay，版权归原作者所有，如需转载，请联系作者。

原文链接：zhangrelay.blog.csdn.net/article/details/121114395