ESP8266 Community Forum

Posted: **Sat Apr 08, 2017 11:30 pm**

Hi all,

Few days ago I bought some ESP modules and started playing with them. I am able to upload a sketch, however I got no response to Serial Monitor. I would expect IP address to connect to and some additional data:

Code: Select all

/*
 *  This sketch demonstrates how to set up a simple HTTP-like server.
 *  The server will set a GPIO pin depending on the request
 *    http://server_ip/gpio/0 will set the GPIO2 low,
 *    http://server_ip/gpio/1 will set the GPIO2 high
 *  server_ip is the IP address of the ESP8266 module, will be 
 *  printed to Serial when the module is connected.
 */

#include <ESP8266WiFi.h>

const char* ssid = "Popelarka";
const char* password = "rony1997";

// Create an instance of the server
// specify the port to listen on as an argument
WiFiServer server(80);

void setup() {
  Serial.begin(115200);
  //Serial.setDebugOutput(true);
  delay(10);

  // prepare GPIO2
  pinMode(5, OUTPUT);
  digitalWrite(5, 0);
  
  // Connect to 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");
  
  // Start the server
  server.begin();
  Serial.println("Server started");

  // Print the IP address
  Serial.println(WiFi.localIP());
}

void loop() {
  // Check if a client has connected
  WiFiClient client = server.available();
  if (!client) {
    return;
  }
  
  // Wait until the client sends some data
  Serial.println("new client");
  while(!client.available()){
    delay(1);
  }
  
  // Read the first line of the request
  String req = client.readStringUntil('\r');
  Serial.println(req);
  client.flush();
  
  // Match the request
  int val;
  if (req.indexOf("/gpio/0") != -1)
    val = 0;
  else if (req.indexOf("/gpio/1") != -1)
    val = 1;
  else {
    Serial.println("invalid request");
    val = 0;
    //client.stop();
  }

  // Set GPIO2 according to the request
  digitalWrite(5, val);
  
  client.flush();

  // Prepare the response
  String s = "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n<!DOCTYPE HTML>\r\n<html>\r\nGPIO is now ";
  s += (val)?"high":"low";
  s += "</html>\n";

  // Send the response to the client
  client.print(s);
  delay(1);
  Serial.println("Client disonnected");

  // The client will actually be disconnected 
  // when the function returns and 'client' object is detroyed
}

The code is barely edited example shipped with ESP arduino library.

I use this wiring for programming:

Code: Select all

ESP <-> USB2Serial
TX   ->    RX
RX   ->   TX
D0   ->   GND
D2   ->   VCC
D15   ->   GND
GND   ->   GND
Reset   ->   Reset
CH_PD   ->   VCC
VCC   ->   +5V

I selected Generic ESP8266 board in Arduino IDE and left all settings without changes.

Programmer: https://www.arduino.cc/en/Main/USBSerial
ESP module: http://www.ebay.com/itm/191981905297?ul_noapp=true

I suppose it is worth to point out, that all pins are soldered by myself - this could lead to some unexpected behavior (I am not good at soldering at all) too.
Could you please give me any suggestions what I am doing wrong?

ESP8266 Community Forum

ESP-12E No serial output

ESP-12E No serial output