Arduino Wifi Shield连接在几秒钟不活动后死亡

Question

我最近购买了Arduino WiFi Shield，并且我已将固件更新到最新版本。

我正在使用Webduino创建一种Web服务，这样我就可以查看pin的状态并将其值设置为HIGH或LOW。

在第一秒内一切正常，但是在几秒钟不活动后，我可以看到红色错误指示灯亮起，之后，当它恢复到网络的连接时，我无法再与屏蔽通信，我必须重启Arduino板。

我在论坛上查了很多帖子，我看到有更多人有同样的问题。他们中的许多人谈论与固件有关的问题，因此看起来有一个错误导致了这个问题。

有谁知道为什么会这样？你能指出我正确的方向吗？

你可以看到我附带的源代码，所以也许你可以看到错误。

    #include <SPI.h>
    #include <WiFi.h>
    #include <Streaming.h>
    #define WEBDUINO_SERIAL_DEBUGGING 1
    #include <WebServer.h>
    #include <sha1.h>

    char ssid[] = "******";
    char pass[] = "******";

    IPAddress ip(192,168,1,210);

    int status = WL_IDLE_STATUS;

    unsigned long sessionId;

    #define WEBDUINO_METHOD_NOT_ALLOWED_MESSAGE "<h1>405 Requested method is not supported for resource</h1>"

    #define CREDENTIALS "********"
    #define PREFIX ""
    #define ANALOG_PINS_AVAILABLE 5
    #define DIGITAL_PINS_AVAILABLE 9

    WebServer webserver(PREFIX, 80);

    void welcome(WebServer &server) {
        P(welcomeMsg1) = "HTTP/1.0 200 OK" CRLF;
        server.printP(welcomeMsg1);

        P(welcomeMsg2) =
                "Content-Type: text/html" CRLF
                CRLF
                "<h1>Welcome to the web service</h1>";

        server.printP(welcomeMsg2);
    }

    void httpMethodNotAllowed(WebServer &server) {
        P(methodNotAllowedMsg1) = "HTTP/1.0 405 Method Not Allowed" CRLF;
        server.printP(methodNotAllowedMsg1);

        P(methodNotAllowedMsg2) =
                "Content-Type: text/html" CRLF
                CRLF
                WEBDUINO_METHOD_NOT_ALLOWED_MESSAGE;

        server.printP(methodNotAllowedMsg2);
    }

    void pinValuesJSON(WebServer &server) {
        char sessionIdHeader[21];

        sprintf(sessionIdHeader, "SessionId: %lu" CRLF, sessionId); 

        server.httpSuccess("application/json; charset=utf-8", sessionIdHeader);

        server << "{";

        server << "\"d2\":" << digitalRead(2) << ",";
        server << "\"d3\":" << digitalRead(3) << ",";
        server << "\"d5\":" << digitalRead(5) << ",";
        server << "\"d6\":" << digitalRead(6);

        server << "}";
    }

    void write(char *pin, char *value) {
        if (pin[0] == 'a') {
            analogWrite(strtoul(pin + 1, NULL, 10), strtoul(value, NULL, 10));
        } else if (pin[0] == 'd') {
            digitalWrite(strtoul(pin + 1, NULL, 10), strtoul(value, NULL, 10));
        }
    }

    void defaultCmd(WebServer &server, WebServer::ConnectionType type, char *url_tail, bool tail_complete) {
        if (server.checkCredentials(CREDENTIALS)) {
            if (type == WebServer::GET) {
                welcome(server);
            } else {
                httpMethodNotAllowed(server);
            }
        } else {
            server.httpUnauthorized();
        }
    }

    void pinsCmd(WebServer &server, WebServer::ConnectionType type, char *url_tail, bool tail_complete) {
    #define PINLEN 5
    #define VALUELEN 5

        if (server.checkCredentials(CREDENTIALS)) {
            if (type == WebServer::GET) {
                pinValuesJSON(server);
            } else if (type == WebServer::PUT) {
                bool repeat;
                char pin[PINLEN];
                char value[VALUELEN];
                do {
                    repeat = server.readPOSTparam(pin, PINLEN, value, VALUELEN);
                    write(pin, value);
                } while (repeat);
                pinValuesJSON(server);
            }
        } else {
            server.httpUnauthorized();
        }
    }

    void setup() {
        randomSeed(analogRead(0));
        sessionId = random(999999999);

        /* Pins
         * 13: SCK
         * 12: MISO
         * 11: MOSI
         * 10: SS for WiFi
         * 9: L9 (yellow) => Informational LED
         * 7: Handshake between shield and Arduino
         * 4: SS for SD card */

        /* When SD card peripheral is not being used, it's necessary to set
         pin 4 as an output and write a high to it */
        pinMode(4, OUTPUT);
        digitalWrite(4, HIGH);

        /* Socket pins */
        pinMode(2, OUTPUT);
        digitalWrite(2, LOW);
        pinMode(3, OUTPUT);
        digitalWrite(3, LOW);
        pinMode(5, OUTPUT);
        digitalWrite(5, LOW);
        pinMode(6, OUTPUT);
        digitalWrite(6, LOW);

        WiFi.config(ip);

        while (status != WL_CONNECTED) {
            // Connect to WPA/WPA2 network. Change this line if using open or WEP network:    
            status = WiFi.begin(ssid, pass);
            delay(4000);
        }

        webserver.setDefaultCommand(&defaultCmd);

        webserver.addCommand("pins", &pinsCmd);

        /* start the webserver */
        webserver.begin();

        digitalWrite(8, HIGH);
    }

    void loop() {
        /* process incoming connections one at a time forever */
        webserver.processConnection();
    }