Arduino: esp8266 connects to wifi, yet I can't access the webpage hosted by the esp8266

[spencerkraisler]

Please fill the info fields, it helps to get you faster support ;)

if you have a stack dump decode it:
https://github.com/esp8266/Arduino/blob/master/doc/Troubleshooting/stack_dump.rst

for better debug messages:
https://github.com/esp8266/Arduino/blob/master/doc/Troubleshooting/debugging.rst

----------------------------- Remove above -----------------------------

Basic Infos

Hardware

Hardware: Wemos D1 mini lite with an esp8266
Core Version: 2.4.0

Description

I upload a basic sketch I got from online on turning the built-in LED on and off over the wifi. The device successfully connects to my school's wifi, yet I cannot access the webpage hosted by the esp8266. A few weeks ago, I did this and was successful at it.

I also turned the Wemos D1 mini lite into a soft AP, and was successful in connecting to it. This shows the board isn't broken or anything, I think.

Settings in IDE

Module: Wemos D1 mini lite
Flash Size: 1 MB
CPU Frequency: 80Mhz
Flash Mode: idk
Flash Frequency: 40Mhz
Upload Using: Microusb
Reset Method: idk

Sketch

include

const char* ssid = "University of Washington";

int led = D4;

WiFiServer server(80);

void setup() {
Serial.begin(74880);
delay(10);
pinMode(led, OUTPUT);

Serial.println();
Serial.println();
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);

WiFi.begin(ssid);
while(WiFi.status() != WL_CONNECTED) {
Serial.println(".");
delay(500);
}
Serial.println("");
Serial.println("WiFi connected");

server.begin();
Serial.println("Server started");

Serial.print("Use this URL: ");
Serial.print("http://");
Serial.print(WiFi.localIP());
Serial.println("/");
}

void loop() {
WiFiClient client = server.available();
if (client == 0) {
return;
}

Serial.println("new client");
while(client.available() == 0) {
delay(1);
}

String request = client.readStringUntil('r');
Serial.println(request);
client.flush();

int value;
if (request.indexOf("/LED=ON") > 0) {
digitalWrite(led, LOW);
value = 1;
}
if (request.indexOf("/LED=OFF") > 0) {
digitalWrite(led, HIGH);
value = 0;
}
Serial.println(value);
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println(""); // do not forget this one
client.println("");
client.println("");

client.print("Led pin is now: ");

if(value == 1) {
client.print("On");
} else {
client.print("Off");
}
client.println("

");
client.println("Click here turn the LED ON
");
client.println("Click here turn the LED OFF
");
client.println("");

delay(1);
Serial.println("Client disconnected");
Serial.println("");

}

Debug Messages

messages here

[5chufti]

does it still work with older core?
maybe port 80 was recently blocked on client (dynamic) IPs?

[spencerkraisler]

@5chufti So I added "#include " and "#include " to the sketch and it worked for some reason. I don't understand why though, since this sketch sued to work without those two lines.

[5chufti]

hmmm, if this includes were missing, it should allready have complained during compile ...
so consider this issue as closed?

[spencerkraisler]

@5chufti it’s literally doing it again, even though I had added the includes. I don’t understand, I literally had it working all proper a few hours ago, and I didn’t change anything.

[spencerkraisler]

@5chufti Boy if you thought things were weird already, wait until you hear this. So I'm wondering if the d1 mini lite can even connect to a webpage. I uploaded a sketch that would extract weather data from a website and although it was successful in connecting to the website, it wouldn't extract any data. Then I go back to the sketch I posted in this thread, and it suddenly began working. It's almost as if the weather sketch woke up the board's "connect to webpage" abilities. I have no idea what's going on.

[schlaegerz]

I also have problems with consistency at time.

Doing this when I setup

ESP.eraseConfig();
WiFi.disconnect();
WiFi.setAutoConnect(false);
WiFi.setAutoReconnect(false);
WiFi.softAP(softAp_ssid.c_str());

seems to help

[devyte]

There have been several fixes merged into the lwip glue since this was opened. Also, the original cause could have been the school networking.
Closing due to age.

[dolby360]

I can see the web page on the esp just prom the computer and not from phone.