实现思路

使用 mini D1 来搭建一个 webSocket 服务，然后使用 nodemcu32 连接，然后就可以进行通信了。

服务端代码（mini D1）

在代码中主要是需要控制好 loop 函数中的延时，也就是最后一行代码 delay，如果太快了板子处理不过来反而会导致实时性很差。设置到 50 到 100 就差不多。

#include <WiFiClient.h>       
#include <WebSocketsServer.h> 
#include <Arduino_JSON.h>// socket 服务
WebSocketsServer webSocket = WebSocketsServer(81);
#define USE_SERIAL Serial// 收到消息后的处理函数
void msg_cb(uint8_t* payload) {// 解析字符串 jsonJSONVar infosObj = JSON.parse((char*)payload);  // 将 payload 转换为 char* if (JSON.typeof(infosObj) == "undefined") {return;}if (infosObj.hasOwnProperty("dj_deg")) {Serial.println((int)infosObj["dj_deg"]);}
}void webSocketEvent(uint8_t num, WStype_t type, uint8_t* payload, size_t length) {switch (type) {case WStype_DISCONNECTED:USE_SERIAL.printf("[%u] Disconnected!\n", num);break;case WStype_CONNECTED:{IPAddress ip = webSocket.remoteIP(num);USE_SERIAL.printf("[%u] Connected from %d.%d.%d.%d url: %s\n", num, ip[0], ip[1], ip[2], ip[3], payload);// send message to clientwebSocket.sendTXT(num, "Connected");}break;case WStype_TEXT:msg_cb(payload);// send message to client// webSocket.sendTXT(num, "message here");// send data to all connected clients// webSocket.broadcastTXT("message here");break;case WStype_BIN:USE_SERIAL.printf("[%u] get binary length: %u\n", num, length);hexdump(payload, length);// send message to client// webSocket.sendBIN(num, payload, length);break;}
}void setup() {Serial.begin(115200);  WiFi.mode(WIFI_AP);                // 将WiFi模式设为APWiFi.softAP("xmio", "12345678");  // 开启热点Serial.println("");IPAddress ip = WiFi.softAPIP();String ipStr = String(ip[0]) + '.' + String(ip[1]) + '.' + String(ip[2]) + '.' + String(ip[3]);String httpUrl = "http://" + ipStr;Serial.println("AP IP:");Serial.println(ipStr);// 开启 scoket 服务webSocket.begin();webSocket.onEvent(webSocketEvent);
}
void loop() {webSocket.loop();delay(50);
}

客户端代码（nodemcu32s ）

和服务端一样，这里的 loop 中也能太快， 50ms 就差不多。要想服务端处理得更快的话其实不使用 json 插件最好。

#include <WiFi.h>
#include <WiFiMulti.h>
#include <HTTPClient.h>
#include <WebSocketsClient.h>
#include <Wire.h>
#include <Arduino_JSON.h>WiFiMulti wifiMulti;
WebSocketsClient webSocket;
#define USE_SERIAL Serialconst String wifi_name = "xmio";
const String wifi_pwd = "12345678";
String wifi_ip = "";            // wifi ip
String ws_connected = "0";      // 已连接 "1"void hexdump(const void* mem, uint32_t len, uint8_t cols = 16) {const uint8_t* src = (const uint8_t*)mem;USE_SERIAL.printf("\n[HEXDUMP] Address: 0x%08X len: 0x%X (%d)", (ptrdiff_t)src, len, len);for (uint32_t i = 0; i < len; i++) {if (i % cols == 0) {USE_SERIAL.printf("\n[0x%08X] 0x%08X: ", (ptrdiff_t)src, i);}USE_SERIAL.printf("%02X ", *src);src++;}USE_SERIAL.printf("\n");
}// socket 监听服务
void webSocketEvent(WStype_t type, uint8_t* payload, size_t length) {switch (type) {case WStype_DISCONNECTED:USE_SERIAL.printf("[WSc] Disconnected!\n");ws_connected = "0";break;case WStype_CONNECTED:USE_SERIAL.printf("[WSc] Connected to url: %s\n", payload);ws_connected = "1";// send message to server when Connected// webSocket.sendTXT("hello");break;case WStype_TEXT:USE_SERIAL.printf("[WSc] get text: %s\n", payload);// send message to server// webSocket.sendTXT("message here");break;case WStype_BIN:USE_SERIAL.printf("[WSc] get binary length: %u\n", length);hexdump(payload, length);// send data to server// webSocket.sendBIN(payload, length);break;case WStype_ERROR:case WStype_FRAGMENT_TEXT_START:case WStype_FRAGMENT_BIN_START:case WStype_FRAGMENT:case WStype_FRAGMENT_FIN:break;}
}void setup() { wifiMulti.addAP(wifi_name.c_str(), wifi_pwd.c_str()); while (wifiMulti.run() != WL_CONNECTED) {// 小车连接中...Serial.println("wifi connect ing...");delay(1000);}String ipAddress = WiFi.gatewayIP().toString();wifi_ip = ipAddress;Serial.println("wifi connected:");Serial.println(wifi_ip);webSocket.begin(wifi_ip, 81, "/");webSocket.onEvent(webSocketEvent);webSocket.setReconnectInterval(5000);
}
void loop(){if (ws_connected == "1") {// 发送一个字符串jsonJSONVar infos;infos["dj_deg"] = dj_deg;String jsonString = JSON.stringify(infos);webSocket.sendTXT(jsonString);}delay(50);
}

效果