ESP8266 Community Forum

- Sun Apr 10, 2016 7:06 am #45216 On start-up, my sketch establishes an Access Point to allow the user to configure SSID/PSK/Params. I allow the Access Point to be available for 60 seconds before switching to Station Mode for the main application.

However, I am getting a consistent connection error in the browser whenever I try to connect with the ESP in WIFI_STA mode after having first used the ESP in WIFI_AP mode. Note that if I don’t connect to the Access Point and just allow the 60 second timeout to occur then the connection to the Station works fine.

Below is a sample sketch that replicates the problem. If you connect to the access point during the first 60 seconds and hit the home page (in this example you will get a “myAPServer found” response in the browser) and then try and connect to the subsequent Station you get a browser connection error. If you don’t connect to the Access Point and just allow the timeout to occur then a connection to the Station will occur fine and a hit on the home page will give a “myServer found” response.

Code: Select all#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>

ESP8266WebServer * myAPServer = NULL;
ESP8266WebServer * myServer = NULL;

const char * SSID = "ENTER SSID";
const char * psk = "ENTER PSK";

bool _continue = false;


void handleRoot(ESP8266WebServer * server, const char * str)
{
   server->send(200, "text/plain", str);
   _continue = true;
}

void setup(void)
{
   Serial.begin(115200);

   WiFi.disconnect();

   Serial.print("\n\n*** Starting AP Portal for 60 seconds.\n");
   Serial.print("*** Connect to TestAP and go to 192.168.4.1 in web browser\n");
   Serial.print("*** You should get a \"myAPServer found\" response\n");

   WiFi.mode(WIFI_AP);
   WiFi.softAP("TestAP");
   myAPServer = new ESP8266WebServer(80);
   myAPServer->on("/", std::bind(handleRoot, myAPServer, "myAPServer found"));
   myAPServer->begin();

   unsigned long start_time = millis();
   while ((millis() - start_time < 60000) && _continue == false) {
      myAPServer->handleClient();
      yield();
   }
   WiFi.softAPdisconnect();
   delete myAPServer;

   Serial.print("\n\n*** Starting STA mode.\n");

   WiFi.mode(WIFI_STA);
   WiFi.begin(SSID, psk);
   if (WiFi.waitForConnectResult() != WL_CONNECTED) {
      Serial.print("Connection Timeout\n");
      ESP.reset();
   }
   myServer = new ESP8266WebServer(80);
   myServer->on("/", std::bind(handleRoot, myServer, "myServer found"));
   myServer->begin();

   Serial.print("*** Connect to usual AP and go to ");
   Serial.print(WiFi.localIP());
   Serial.print(" in web browser.\n");
   Serial.print("*** I get a \"connection error\" rather than \"myServer found\" response\n");
   delay(5000);
}

void loop(void) {
   myServer->handleClient();
}


Appreciate any thoughts on the above even if it is only confirmation that the error can be replicated! This is on a NodeMCU 1.0 (ESP-12E Module) with SDK 1.5.1 and ESP8266 2.1.0