NodeMcu as SoftAP. Access Point. Send message. WebServer. LCD.

[Juan Antonio]

Hello friends,

NodeMcu as SoftAP.

Three ways to use NodeMcu in a network:

1.- Router connected to the Internet and NodeMcu client of that router. 

- NodeMcu works as WebServer in that local network.

- If you open port 80 in Router, you can get that WebServer from Internet [https://portforward.com/]

  2.- Router not connected to the Internet and NodeMcu client of that router.

- NodeMcu works as WebServer in that local network.

- You do not need internet. 

3.- NodeMcu as SoftAP (Access Point).

- You do not need Router.

- NodeMcu creates network 192.168.4.X

- NodeMcu works as WebServer in that local network.

- In this example, when you Click Button1,2,3,4 in App Inventor (Android), it sends a static message ("Juan Antonio", "KIO4.COM"...)

- When Click Button5, it sends text in TextBox1.

- These messages, NodeMcu shows them on an LCD

- Look IP, 192.168.4.22

- Code for NodeMcu:

- NodeMcu is a SoftAP and a Web Server.

- Name network: ESPsoftAP_01 (without password).

// Juan A. Villalpando
// NodeMcu como Punto de Acceso y Servidor Web.

#include <ESP8266WiFi.h>
// SoftAP
IPAddress local_IP(192,168,4,22);
IPAddress gateway(192,168,4,9);
IPAddress subnet(255,255,255,0);
// Web Server
WiFiServer server(80);
// LCD
#include <LiquidCrystal_I2C.h>    
LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);
// LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);
#include <Wire.h>
String value = "-"; 

void setup()
{
  Serial.begin(115200);
  lcd.begin(16,2);// Columnas y filas de LCD 
  delay(10);
  Serial.println();

  Serial.print("Setting soft-AP configuration ... ");
  Serial.println(WiFi.softAPConfig(local_IP, gateway, subnet) ? "Ready" : "Failed!");

  Serial.print("Setting soft-AP ... ");
  Serial.println(WiFi.softAP("ESPsoftAP_01") ? "Ready" : "Failed!");

  Serial.print("Soft-AP IP address = ");
  Serial.println(WiFi.softAPIP());
  server.begin();
}

void loop() {
  // Consulta si se ha conectado algún cliente.
  WiFiClient client = server.available();
  if (!client) {
    return;
  }
 
  // Espera hasta que el cliente envíe datos.
  Serial.println("Nuevo cliente.");
  while(!client.available()){
    delay(1);
  }
 
  // Lee la primera línea de la petición.
  String request = client.readStringUntil('\r');
  Serial.println(request);
  client.flush();
 
  // Consulta la petición
  if (request.startsWith("mensaje=1", 5))  { value = "Juan Antonio";}
  if (request.startsWith("mensaje=2", 5))  { value = "KIO4.COM.";}
  if (request.startsWith("mensaje=3", 5))  { value = "Buen tiempo.";}
  if (request.startsWith("mensaje=4", 5))  { value = "Puerto Real";}
  if (request.startsWith("x", 15))  {  // Si en la posición 15 viene una x...
    value = request.substring(17);     // ... un mensaje comienza en la 17.
    value.replace("+", " ");           // Para que los espacios no salgan con +
    value.replace(" HTTP/1.1", " ");   // Para quitar HTTP/1.1
    }

  Serial.println(value);
  lcd.clear(); // Borra pantalla
  lcd.setCursor(0,0); // Inicio del cursor
  lcd.print(value);

  // Devuelve el mensaje.
  client.println("HTTP/1.1 200 OK");
  client.println("Content-Type: text/html");
  client.println(""); //  Comillas importantes.
  client.print(value);
 
  Serial.println("Cliente desconectado.");
  }

////////////////////////////////////////////////////////////////////////

- To check the operation, install the application (not emulate with MIT Companion) and in your Wifi network configuration, establish the network "ESPsoftAP_01" (192.168.4.x)

- More information:

 https://arduino-esp8266.readthedocs.io/en/latest/esp8266wifi/readme.html

 https://arduino-esp8266.readthedocs.io/en/latest/esp8266wifi/soft-access-point-class.html

http://kio4.com/arduino/75_nodemcu_punto_acceso.htm (It is in Spanish)

Regards.

Juan Antonio Villalpando.

[ABG]

(added to new NodeMCU section of FAQ)

https://sites.google.com/view/ai2-faq-view/home

ABG