{"id":89227,"date":"2019-09-13T13:10:22","date_gmt":"2019-09-13T13:10:22","guid":{"rendered":"https:\/\/randomnerdtutorials.com\/?p=89227"},"modified":"2019-09-13T13:10:28","modified_gmt":"2019-09-13T13:10:28","slug":"esp8266-nodemcu-access-point-ap-web-server","status":"publish","type":"post","link":"https:\/\/randomnerdtutorials.com\/esp8266-nodemcu-access-point-ap-web-server\/","title":{"rendered":"ESP8266 NodeMCU Access Point (AP) for Web Server"},"content":{"rendered":"\n

In this tutorial, you’ll learn how to set your ESP8266 NodeMCU as an Access Point (AP) using Arduino IDE. This allows you to connect directly to your ESP8266 via Wi-Fi without a wireless router.<\/p>\n\n\n\n

\"ESP8266<\/figure><\/div>\n\n\n\n

To set the ESP8266 as an Access Point use WiFi.softAP(ssid, password);<\/span> <\/p>\n\n\n\n

ESP8266 Station and Access Point<\/h2>\n\n\n\n

In most of our ESP8266 NodeMCU web server projects<\/a>, we connect the ESP8266 to a wireless router. In this configuration, we can access the ESP8266 through the local network.<\/p>\n\n\n\n

In this scenario, the router acts as an access point and the ESP8266 is set as a station. So, you need to be connected to your router (local network) to control the ESP8266.<\/p>\n\n\n\n

\"ESP866<\/figure><\/div>\n\n\n\n

In some cases, this might not be the best configuration (when you don’t have a router nearby). But if you set the ESP8266 as an access point (hotspot), you can be connected to the ESP8266 using any device with Wi-Fi capabilities without the need to connect to your router.<\/p>\n\n\n\n

In simple words, when you set the ESP8266 as an access point you create its own Wi\u2011Fi network and nearby Wi-Fi devices (stations) can connect to it (like your smartphone or your computer).<\/p>\n\n\n\n

\"ESP866<\/figure><\/div>\n\n\n\n

In this tutorial, we\u2019ll show you how to set the ESP8266 as an access point in your web server projects. This way, you don\u2019t need to be connected to a router to control your ESP8266.<\/p>\n\n\n\n

Because the ESP8266 doesn\u2019t connect further to a wired network (like your router), it is called soft-AP (soft Access Point).<\/p>\n\n\n\n

This means that if you try to load libraries or use firmware from the internet, it will not work. It also doesn’t work if you try to make HTTP requests to services on the internet like publishing sensor readings to the cloud.<\/p>\n\n\n\n

Installing the DHT Library for ESP8266<\/h2>\n\n\n\n

For this example, we’ll use a previous web server project that displays sensor readings from a DHT sensor<\/a>. <\/p>\n\n\n\n

Having the ESP8266 Board installed in Arduino IDE<\/a>, to read from the DHT sensor, we\u2019ll use the DHT library from Adafruit<\/a>. To use this library you also need to install the Adafruit Unified Sensor library<\/a>. <\/p>\n\n\n\n

Follow the next steps to install those two libraries:<\/p>\n\n\n\n

1. Open your Arduino IDE and go to Sketch <\/strong>> Include Library<\/strong> > Manage Libraries<\/strong>. The Library Manager should open.<\/p>\n\n\n\n

2. Search for \u201cDHT<\/strong>\u201d on the Search box and install the DHT library from Adafruit.<\/p>\n\n\n\n

\"Installing<\/figure><\/div>\n\n\n\n

3. After installing the DHT library from Adafruit, type \u201cAdafruit Unified Sensor<\/strong>\u201d in the search box. Scroll all the way down to find the library and install it.<\/p>\n\n\n\n

\"Installing<\/figure><\/div>\n\n\n\n

After installing the libraries, restart your Arduino IDE.<\/p>\n\n\n\n

ESP8266 NodeMCU Access Point (AP)<\/h2>\n\n\n\n

In this example, we\u2019ll modify the ESP8266 Web Server from a previous tutorial to add access point capabilities. Here’s the project example we’ll use: ESP8266 DHT11\/DHT22 Temperature and Humidity Web Server with Arduino IDE<\/a>.<\/p>\n\n\n\n

What we\u2019ll show you here can be used with any ESP8266 web server example.<\/p>\n\n\n\n

Upload the sketch provided below to set the ESP8266 as an access point.<\/p>\n\n\n

\/*********\n  Rui Santos & Sara Santos - Random Nerd Tutorials\n  Complete project details at https:\/\/randomnerdtutorials.com\/esp8266-nodemcu-access-point-ap-web-server\/\n  Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files.\n  The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.\n*********\/\n\n\/\/ Import required libraries\n#include <Arduino.h>\n#include <ESP8266WiFi.h>\n#include <Hash.h>\n#include <ESPAsyncTCP.h>\n#include <ESPAsyncWebServer.h>\n#include <Adafruit_Sensor.h>\n#include <DHT.h>\n\nconst char* ssid     = "ESP8266-Access-Point";\nconst char* password = "123456789";\n\n#define DHTPIN 5     \/\/ Digital pin connected to the DHT sensor\n\n\/\/ Uncomment the type of sensor in use:\n\/\/#define DHTTYPE    DHT11     \/\/ DHT 11\n#define DHTTYPE    DHT22     \/\/ DHT 22 (AM2302)\n\/\/#define DHTTYPE    DHT21     \/\/ DHT 21 (AM2301)\n\nDHT dht(DHTPIN, DHTTYPE);\n\n\/\/ current temperature & humidity, updated in loop()\nfloat t = 0.0;\nfloat h = 0.0;\n\n\/\/ Create AsyncWebServer object on port 80\nAsyncWebServer server(80);\n\n\/\/ Generally, you should use "unsigned long" for variables that hold time\n\/\/ The value will quickly become too large for an int to store\nunsigned long previousMillis = 0;    \/\/ will store last time DHT was updated\n\n\/\/ Updates DHT readings every 10 seconds\nconst long interval = 10000;  \n\nconst char index_html[] PROGMEM = R"rawliteral(\n<!DOCTYPE HTML><html>\n<head>\n  <meta name="viewport" content="width=device-width, initial-scale=1">\n  <style>\n    html {\n     font-family: Arial;\n     display: inline-block;\n     margin: 0px auto;\n     text-align: center;\n    }\n    h2 { font-size: 3.0rem; }\n    p { font-size: 3.0rem; }\n    .units { font-size: 1.2rem; }\n    .dht-labels{\n      font-size: 1.5rem;\n      vertical-align:middle;\n      padding-bottom: 15px;\n    }\n  <\/style>\n<\/head>\n<body>\n  <h2>ESP8266 DHT Server<\/h2>\n  <p>\n    <span class="dht-labels">Temperature<\/span> \n    <span id="temperature">%TEMPERATURE%<\/span>\n    <sup class="units">&deg;C<\/sup>\n  <\/p>\n  <p>\n    <span class="dht-labels">Humidity<\/span>\n    <span id="humidity">%HUMIDITY%<\/span>\n    <sup class="units">%<\/sup>\n  <\/p>\n<\/body>\n<script>\nsetInterval(function ( ) {\n  var xhttp = new XMLHttpRequest();\n  xhttp.onreadystatechange = function() {\n    if (this.readyState == 4 && this.status == 200) {\n      document.getElementById("temperature").innerHTML = this.responseText;\n    }\n  };\n  xhttp.open("GET", "\/temperature", true);\n  xhttp.send();\n}, 10000 ) ;\n\nsetInterval(function ( ) {\n  var xhttp = new XMLHttpRequest();\n  xhttp.onreadystatechange = function() {\n    if (this.readyState == 4 && this.status == 200) {\n      document.getElementById("humidity").innerHTML = this.responseText;\n    }\n  };\n  xhttp.open("GET", "\/humidity", true);\n  xhttp.send();\n}, 10000 ) ;\n<\/script>\n<\/html>)rawliteral";\n\n\/\/ Replaces placeholder with DHT values\nString processor(const String& var){\n  \/\/Serial.println(var);\n  if(var == "TEMPERATURE"){\n    return String(t);\n  }\n  else if(var == "HUMIDITY"){\n    return String(h);\n  }\n  return String();\n}\n\nvoid setup(){\n  \/\/ Serial port for debugging purposes\n  Serial.begin(115200);\n  dht.begin();\n  \n  Serial.print("Setting AP (Access Point)\u2026");\n  \/\/ Remove the password parameter, if you want the AP (Access Point) to be open\n  WiFi.softAP(ssid, password);\n\n  IPAddress IP = WiFi.softAPIP();\n  Serial.print("AP IP address: ");\n  Serial.println(IP);\n\n  \/\/ Print ESP8266 Local IP Address\n  Serial.println(WiFi.localIP());\n\n  \/\/ Route for root \/ web page\n  server.on("\/", HTTP_GET, [](AsyncWebServerRequest *request){\n    request->send(200, "text\/html", index_html, processor);\n  });\n  server.on("\/temperature", HTTP_GET, [](AsyncWebServerRequest *request){\n    request->send(200, "text\/plain", String(t).c_str());\n  });\n  server.on("\/humidity", HTTP_GET, [](AsyncWebServerRequest *request){\n    request->send(200, "text\/plain", String(h).c_str());\n  });\n\n  \/\/ Start server\n  server.begin();\n}\n \nvoid loop(){  \n  unsigned long currentMillis = millis();\n  if (currentMillis - previousMillis >= interval) {\n    \/\/ save the last time you updated the DHT values\n    previousMillis = currentMillis;\n    \/\/ Read temperature as Celsius (the default)\n    float newT = dht.readTemperature();\n    \/\/ Read temperature as Fahrenheit (isFahrenheit = true)\n    \/\/float newT = dht.readTemperature(true);\n    \/\/ if temperature read failed, don't change t value\n    if (isnan(newT)) {\n      Serial.println("Failed to read from DHT sensor!");\n    }\n    else {\n      t = newT;\n      Serial.println(t);\n    }\n    \/\/ Read Humidity\n    float newH = dht.readHumidity();\n    \/\/ if humidity read failed, don't change h value \n    if (isnan(newH)) {\n      Serial.println("Failed to read from DHT sensor!");\n    }\n    else {\n      h = newH;\n      Serial.println(h);\n    }\n  }\n}\n<\/code><\/pre>\n\t
View raw code<\/a><\/p>\n\n\n\n
Customize the SSID and Password<\/h3>\n\n\n\n
You need to define a SSID name and a password to access the ESP8266. In this example we\u2019re setting the ESP8266 SSID name to ESP8266-Access-Point<\/span>, but you can modify the name to whatever you want. The password is 123456789<\/span>, but you can also modify it.<\/p>\n\n\n\n
const char* ssid     = \"ESP8266-Access-Point\";\nconst char* password = \"123456789\";<\/code><\/pre>\n\n\n\n
Setting the ESP8266 as an Access Point (AP)<\/h3>\n\n\n\n
There\u2019s a section in the setup()<\/span> to set the ESP8266 as an access point using the softAP()<\/span> method:<\/p>\n\n\n\n
WiFi.softAP(ssid, password);<\/code><\/pre>\n\n\n\n
There are also other optional parameters you can pass to the softAP()<\/span> method. Here\u2019s all the parameters:<\/p>\n\n\n\n
.softAP(const char* ssid, const char* password, int channel, int ssid_hidden, int max_connection)<\/code><\/pre>\n\n\n\n