<p>Registering the "not found" handler is a different way than ESP8266WebServer (WebServer as ESP32). The <em>onNotFound</em> of ESP8266WebServer/WebServer does not work with AutoConnect. AutoConnect overrides <em>ESP8266WebServer::onNotFound</em>/<em>WebServer::onNotFound</em> to handle a captive portal. To register "not found" handler, use <ahref="api.html#onnotfound"><em>AutoConnect::onNotFound</em></a>.</p>
<h3id="access-to-saved-credentials"><iclass="fa fa-caret-right"></i> Access to saved credentials<aclass="headerlink"href="#access-to-saved-credentials"title="Permanent link">¶</a></h3>
<p>AutoConnect stores the established WiFi connection in the flash of the ESP8266/ESP32 module and equips the class to access it from the sketch. You can read, write or erase the credentials using this class individually. It's <ahref="credit.html#autoconnectcredential">AutoConnectCredential</a> class which provides the access method to the saved credentials in the flash. Refer to section <ahref="credit.html">Saved credentials access</a> for details.</p>
<divclass="admonition note">
<pclass="admonition-title">Where to store credentials in ESP32 with AutoConnect v1.0.0 or later</p>
<p>Since v1.0.0, credentials are stored in nvs of ESP32. AutoConnect v1.0.0 or later accesses the credentials area using the <strong>Preferences</strong> class with the arduino esp-32 core. So in ESP32, the credentials are not in the EEPROM, it is in the namespace <strong>AC_CREDT</strong> of the nvs. See <ahref="credit.html">Saved credentials access</a> for details.<br/>
In ESP8266, it is saved in EEPROM as is conventionally done.</p>
<p>When the captive portal is started, SoftAP starts and the STA is disconnected. The current SSID setting memorized in ESP8266 will be lost but then the reconnect behavior of ESP32 is somewhat different from this.</p>
<p>The <ahref="https://github.com/espressif/arduino-esp32/blob/a0f0bd930cfd2d607bf3d3288f46e2d265dd2e11/libraries/WiFi/src/WiFiSTA.h#L46"><em>WiFiSTAClass::disconnect</em></a> function implemented in the arduino-esp32 has extended parameters than the ESP8266's arduino-core. The second parameter of WiFi.disconnect on the arduino-esp32 core that does not exist in the <ahref="https://github.com/esp8266/Arduino/blob/7e1bdb225da8ab337373517e6a86a99432921a86/libraries/ESP8266WiFi/src/ESP8266WiFiSTA.cpp#L296">ESP8266WiFiSTAClass</a> has the effect of deleting the currently connected WiFi configuration and its default value is "false". On the ESP32 platform, even if WiFi.disconnect is executed, WiFi.begin() without the parameters in the next turn will try to connect to that AP. That is, automatic reconnection is implemented in arduino-esp32 already. Although this behavior appears seemingly competent, it is rather a disadvantage in scenes where you want to change the access point each time. When explicitly disconnecting WiFi from the Disconnect menu, AutoConnect will erase the AP connection settings saved by arduino-esp32 core. AutoConnect's automatic reconnection is a mechanism independent from the automatic reconnection of the arduino-esp32 core.</p>
<p>If the <ahref="apiconfig.html#autoreconnect"><strong>autoReconnect</strong></a> option of the <ahref="apiconfig.html">AutoConnectConfig</a> class is enabled, it automatically attempts to reconnect to the disconnected past access point. When the autoReconnect option is specified, AutoConnect will not start SoftAP immediately if the first WiFi.begin fails. It will scan WiFi signal and the same connection information as the detected BSSID is stored in the flash as AutoConnect's credentials, explicitly apply it with WiFi.begin and rerun.</p>
<pclass="admonition-title">An autoReconnect will work if SSID detection succeeded</p>
<p>An autoReconnect will not effect if the SSID which stored credential to be connected is a hidden access point.</p>
</div>
<h3id="auto-save-credential"><iclass="fa fa-caret-right"></i> Auto save Credential<aclass="headerlink"href="#auto-save-credential"title="Permanent link">¶</a></h3>
<p>By default, AutoConnect saves the credentials of the established connection to the flash. You can disable it with the <ahref="apiconfig.html#autosave"><strong>autoSave</strong></a> parameter specified by <ahref="apiconfig.html">AutoConnectConfig</a>.<br/>
See the <ahref="credit.html">Saved credentials access</a> chapter for details on accessing stored credentials.</p>
<p>The captive portal will only be activated if the first <em>WiFi::begin</em> fails. Sketch can detect with the <ahref="api.html#ondetect"><em>AutoConnect::onDetect</em></a> function that the captive portal has started. For example, the sketch can be written like as follows that turns on the LED at the start captive portal.</p>
<p>AutoConnect has two parameters for timeout control. One is a timeout value used when trying to connect to the specified AP. It behaves the same as general timeout control in connection attempt by WiFi.begin. This control is specified by the third parameter of <ahref="api.html#begin"><em>AutoConnect::begin</em></a>. The default value is macro defined by <ahref="api.html#defined-macros"><strong>AUTOCONNECT_TIMEOUT</strong></a> in the <strong>AutoConnectDef.h</strong> file.</p>
<p>The other timeout control is for the captive portal itself. It is useful when you want to continue sketch execution with offline even if the WiFi connection is not possible. You can also combine it with the <ahref="#on-demand-start-the-captive-portal"><strong>immediateStart</strong></a> option to create sketches with high mobility.</p>
<p>The timeout of the captive portal is specified together with <ahref="apiconfig.html#portaltimeout"><em>AutoConnectConfig::portalTimeout</em></a> as follows.</p>
<spanstyle="background-color: #49483e"><spanstyle="color: #f8f8f2">config.portalTimeout</span><spanstyle="color: #f92672">=</span><spanstyle="color: #ae81ff">60000</span><spanstyle="color: #f8f8f2">;</span><spanstyle="color: #75715e">// It will time out in 60 seconds</span>
Also, if you want to stop AutoConnect completely when the captive portal is timed out, you need to call the <ahref="api.html#end"><em>AutoConnect::end</em></a> function. It looks like the following code:</p>
<spanstyle="color: #f8f8f2">config.portalTimeout</span><spanstyle="color: #f92672">=</span><spanstyle="color: #ae81ff">60000</span><spanstyle="color: #f8f8f2">;</span><spanstyle="color: #75715e">// It will time out in 60 seconds</span>
<p>There is another option related to timeout in AutoConnectConfig. It can make use of the captive portal function even after a timeout. The <ahref="apiconfig.html#retainportal"><em>AutoConnectConfig::retainPortal</em></a> option will not stop the SoftAP when the captive portal is timed out. If you enable the ratainPortal option, you can try to connect to the AP at any time while continuing to sketch execution with offline even after the captive portal timed-out. Compared to the above code specified no option with the following example code, the captive portal will remain available even after a timeout without changing the logic of the sketch.</p>
<spanstyle="color: #f8f8f2">config.portalTimeout</span><spanstyle="color: #f92672">=</span><spanstyle="color: #ae81ff">60000</span><spanstyle="color: #f8f8f2">;</span><spanstyle="color: #75715e">// It will time out in 60 seconds</span>
<h3id="casts-the-html-pages-to-be-add-on-into-the-menu"><iclass="fa fa-caret-right"></i> Casts the HTML pages to be add-on into the menu<aclass="headerlink"href="#casts-the-html-pages-to-be-add-on-into-the-menu"title="Permanent link">¶</a></h3>
<p>If your sketch handles web pages, you can embed the pages into the AutoConnect menu in continuance enjoying the utility of the WiFi connection feature. Unlike the custom Web pages by <ahref="acelements.html">AutoConnectElements</a>, this allows to legacy web pages registered by <em>ESP8266WebServer::on</em> or <em>WebServer::on</em> function.</p>
<p>To implement embedding your legacy web pages to the AutoConnect menu, you can use AutoConnectAux only constructed with the URI of the page to be embedding. AutoConnectElements is not required. The basic procedure for this as follows:</p>
<li>Register AutoConnectAux declared with #1 to AutoConnect using <ahref="api.html#join"><em>AutoConnect::join</em></a> function. It serves as a menu item.</li>
<p>Although the default menu title is <strong>AutoConnect</strong>, you can change the title by setting <ahref="apiconfig.html#title"><em>AutoConnectConfig::title</em></a>. To set the menu title properly, you must set before calling <ahref="api.html#begin"><em>AutoConnect::begin</em></a>.</p>
<h3id="change-the-menu-labels"><iclass="fa fa-caret-right"></i> Change the menu labels<aclass="headerlink"href="#change-the-menu-labels"title="Permanent link">¶</a></h3>
<p>You can change the label of the AutoConnect menu item by rewriting the default label letter in <ahref="https://github.com/Hieromon/AutoConnect/blob/master/src/AutoConnectLabels.h">AutoConnectLabels.h</a> macros. However, changing menu items letter influences all the sketch's build scenes.</p>
<divclass="codehilite"style="background: #272822"><prestyle="line-height: 125%"><span></span><spanstyle="color: #75715e">#define AUTOCONNECT_MENULABEL_CONFIGNEW "Configure new AP"</span>
<h3id="combination-with-mdns"><iclass="fa fa-caret-right"></i> Combination with mDNS<aclass="headerlink"href="#combination-with-mdns"title="Permanent link">¶</a></h3>
<p>With <ahref="https://github.com/esp8266/Arduino/tree/master/libraries/ESP8266mDNS">mDNS library</a>, you can access to ESP8266 by name instead of IP address after connection. The sketch can start the MDNS responder after <ahref="api.html#begin"><em>AutoConnect::begin</em></a>.</p>
<p>You can output AutoConnect monitor messages to the <strong>Serial</strong>. A monitor message activation switch is in an include header file <ahref="https://github.com/Hieromon/AutoConnect/blob/master/src/AutoConnectDefs.h">AutoConnectDefs.h</a> of library source. Define <ahref="https://github.com/Hieromon/AutoConnect/blob/master/src/AutoConnectDefs.h#L14"><strong>AC_DEBUG</strong></a> macro to output the monitor messages.<supid="fnref:1"><aclass="footnote-ref"href="#fn:1"rel="footnote">1</a></sup></p>
<h3id="disable-the-captive-portal"><iclass="fa fa-caret-right"></i> Disable the captive portal<aclass="headerlink"href="#disable-the-captive-portal"title="Permanent link">¶</a></h3>
<p>It can also prevent the captive portal from starting even if the connection at the first <em>WiFi.begin</em> fails. In this case, <ahref="api.html#begin"><em>AutoConnect::begin</em></a> behaves same as <em>WiFi.begin</em>.</p>
<p>For disabling the captive portal, <ahref="apiconfig.html#autorise"><strong>autoRise</strong></a> sets to false with <ahref="apiconfig.html">AutoConnectConfig</a>.</p>
<h3id="make-ssid-of-softap-unique"><iclass="fa fa-caret-right"></i> Make SSID of SoftAP unique<aclass="headerlink"href="#make-ssid-of-softap-unique"title="Permanent link">¶</a></h3>
<p>You can change SoftAP's SSID and password programmatically when the captive portal starts up. By using chip specific ID of esp8266/esp32 you can make SSID of SoftAP unique. SSID and password for SoftAP is <ahref="apiconfig.html#apid"><em>AutoConnectConfig::apid</em></a> and <ahref="apiconfig.html#psk"><em>AutoConnectConfig::psk</em></a>.</p>
<h3id="move-the-saving-area-of-eeprom-for-the-credentials"><iclass="fa fa-caret-right"></i> Move the saving area of EEPROM for the credentials<aclass="headerlink"href="#move-the-saving-area-of-eeprom-for-the-credentials"title="Permanent link">¶</a></h3>
<p>By default, the credentials saving area is occupied from the beginning of EEPROM area. <ahref="http://arduino-esp8266.readthedocs.io/en/latest/filesystem.html?highlight=eeprom#flash-layout">ESP8266 Arduino core document</a> says that:</p>
<blockquote>
<p>The following diagram illustrates flash layout used in Arduino environment:</p>
<p>EEPROM library uses one sector of flash located <ahref="http://arduino-esp8266.readthedocs.io/en/latest/libraries.html?highlight=SPIFFS#eeprom">just after the SPIFFS</a>.</p>
<p>Also, in ESP32 arduino core 1.0.2 earlier, the placement of the EEPROM area of ESP32 is described in the <ahref="https://github.com/espressif/arduino-esp32/blob/master/tools/partitions/default.csv">partition table</a>. So in the default state, the credential storage area used by AutoConnect conflicts with data owned by the user sketch. It will be destroyed together saved data in EEPROM by user sketch and AutoConnect each other. But you can move the storage area to avoid this.</p>
<p>The <ahref="apiconfig.html#boundaryoffset"><strong>boundaryOffset</strong></a> in <ahref="apiconfig.html">AutoConnectConfig</a> specifies the start offset of the credentials storage area. The default value is 0.</p>
<pclass="admonition-title">The boundaryOffset ignored with AutoConnect v1.0.0 later on ESP32 arduino core 1.0.3 later</p>
<p>For ESP32 arduino core 1.0.3 and later, AutoConnect will store credentials to Preferences in the nvs. Since it is defined as the namespace dedicated to AutoConnect and separated from the area used for user sketches. Therefore, the boundaryOffet is ignored with the combination of AutoConnect v1.0.0 or later and the arduino-esp32 1.0.3 or later.</p>
<p>If you do not usually connect to WiFi and need to establish a WiFi connection if necessary, you can combine the <ahref="apiconfig.html#autorise"><strong>autoRise</strong></a> option with the <ahref="apiconfig.html#immediatestart"><strong>immediateStart</strong></a> option to achieve on-demand connection. This behavior is similar to the <ahref="https://github.com/tzapu/WiFiManager#on-demand-configuration-portal">WiFiManager's startConfigPortal</a> function. In order to do this, you usually configure only with AutoConnectConfig in <em>setup()</em> and <ahref="api.html#begin"><em>AutoConnect::begin</em></a> handles in <em>loop()</em>.</p>
The above example does not connect to WiFi until TRIGGER_PIN goes LOW. When TRIGGER_PIN goes LOW, the captive portal starts and you can connect to WiFi. Even if you reset the module, it will not automatically reconnect.</p>
<h3id="refers-the-hosted-esp8266webserverwebserver"><iclass="fa fa-caret-right"></i> Refers the hosted ESP8266WebServer/WebServer<aclass="headerlink"href="#refers-the-hosted-esp8266webserverwebserver"title="Permanent link">¶</a></h3>
<p>Constructing an AutoConnect object variable without parameters then creates and starts an ESP8266WebServer/WebServer inside the AutoConnect. This object variable could be referred by <ahref="api.html#host"><em>AutoConnect::host</em></a> function to access ESP8266WebServer/WebServer instance as like below.</p>
<pclass="admonition-title">When host() is valid</p>
<p>The host() can be referred at after <em>AutoConnect::begin</em>.</p>
</div>
<h3id="usage-for-automatically-instantiated-esp8266webserverwebserver"><iclass="fa fa-caret-right"></i> Usage for automatically instantiated ESP8266WebServer/WebServer<aclass="headerlink"href="#usage-for-automatically-instantiated-esp8266webserverwebserver"title="Permanent link">¶</a></h3>
<p>The sketch can handle URL requests using ESP8266WebServer or WebServer that AutoConnect started internally. ESP8266WebServer/WebServer instantiated dynamically by AutoConnect can be referred to by <ahref="api.html#host"><em>AutoConnect::host</em></a> function. The sketch can use the '<strong>on</strong>' function, '<strong>send</strong>' function, '<strong>client</strong>' function and others by ESP8266WebServer/WebServer reference of its return value.</p>
<pclass="admonition-title">ESP8266WebServer/WebServer function should be called after AutoConnect::begin</p>
<p>The sketch cannot refer to an instance of ESP8266WebServer/WebServer until AutoConnect::begin completes successfully.</p>
</div>
<divclass="admonition warning">
<pclass="admonition-title">Do not use with ESP8266WebServer::begin or WebServer::begin</p>
<p>ESP8266WebServer/WebServer is already running inside the AutoConnect.</p>
</div>
<h3id="use-with-the-pagebuilder-library"><iclass="fa fa-caret-right"></i> Use with the <ahref="https://github.com/Hieromon/PageBuilder">PageBuilder</a> library<aclass="headerlink"href="#use-with-the-pagebuilder-library"title="Permanent link">¶</a></h3>
<p>In ordinary, the URL handler will respond the request by sending some HTML. <ahref="https://github.com/Hieromon/PageBuilder">PageBuilder</a> library is HTML assembly aid. it can handle predefined HTML as like a template and simplify an HTML string assemble logic, and also the generated HTML send automatically.</p>
<p>An example sketch used with the PageBuilder as follows and it explains how it aids for the HTML generating. Details for <ahref="https://github.com/Hieromon/PageBuilder">Github repository</a>.</p>
<h3id="configuration-for-soft-ap-and-captive-portal"><iclass="fa fa-caret-right"></i> Configuration for Soft AP and captive portal<aclass="headerlink"href="#configuration-for-soft-ap-and-captive-portal"title="Permanent link">¶</a></h3>
<p>AutoConnect will activate SoftAP at failed the first <em>WiFi.begin</em>. It SoftAP settings are stored in <ahref="apiconfig.html#autoconnectconfig"><strong>AutoConnectConfig</strong></a> as the following parameters. The sketch could be configured SoftAP using these parameters, refer the <ahref="apiconfig.html#public-member-variables">AutoConnectConfig API</a> for details.</p>
<pclass="admonition-title">AutoConnect::config before AutoConnect::begin</p>
<p><em>AutoConnect::config</em> must be executed before <em>AutoConnect::begin</em>.</p>
</div>
<h3id="assign-user-sketchs-home-path"><iclass="fa fa-caret-right"></i> Assign user sketch's home path<aclass="headerlink"href="#assign-user-sketchs-home-path"title="Permanent link">¶</a></h3>
<p><strong>HOME</strong> for returning to the user's sketch homepage will display at the bottom of the AutoConnect menu. It could be set using the <ahref="api.html#home"><em>AutoConnect::home</em></a> function.</p>
<h3id="change-ssid-and-password-for-softap"><iclass="fa fa-caret-right"></i> Change SSID and Password for SoftAP<aclass="headerlink"href="#change-ssid-and-password-for-softap"title="Permanent link">¶</a></h3>
<p>An <strong>esp8266ap</strong> is default SSID name for SoftAP of captive portal and password is <strong>12345678</strong> for ESP8266. Similarly, <strong>esp32ap</strong> and <strong>12345678</strong> for ESP32. You can change both by setting <ahref="apiconfig.html#apid">apid</a> and <ahref="apiconfig.html#psk">psk</a>.</p>
<p>You can also assign no password to SoftAP launched as a captive portal. Assigning a null string as <code>String("")</code> to <ahref="apiconfig.html#psk">AutoConnectConfig::psk</a> does not require a password when connecting to SoftAP.<br/>
But this method is not recommended. The broadcast radio of SSID emitted from SoftAP will leak and reach several tens of meters.</p>
<h3id="relocate-the-autoconnect-home-path"><iclass="fa fa-caret-right"></i> Relocate the AutoConnect home path<aclass="headerlink"href="#relocate-the-autoconnect-home-path"title="Permanent link">¶</a></h3>
<p>A home path of AutoConnect is <strong>/_ac</strong> by default. You can access from the browser with http://IPADDRESS/_ac. You can change the home path by revising <ahref="https://github.com/Hieromon/AutoConnect/blob/master/src/AutoConnectDefs.h#L62"><strong>AUTOCONNECT_URI</strong></a> macro in the include header file as <ahref="https://github.com/Hieromon/AutoConnect/blob/master/src/AutoConnectDef.h">AutoConnectDef.h</a>.</p>
<h3id="static-ip-assignment-2"><iclass="fa fa-caret-right"></i> Static IP assignment <supid="fnref:2"><aclass="footnote-ref"href="#fn:2"rel="footnote">2</a></sup><aclass="headerlink"href="#static-ip-assignment-2"title="Permanent link">¶</a></h3>
<p>It is also possible to assign static IP Address to ESP8266/ESP32 in STA mode. By default DHCP is enabled and it becomes the IP address assigned by the DHCP server with <em>WiFi.begin</em>.</p>
<p>To assign a static IP to ESP8266/ESP32 with WIFI_MODE_STA, the following parameters are required:</p>
<p><ahref="apiconfig.html#hostname">AutoConnectConfig::hostName</a> assigns the station DHCP hostname which complies with <ahref="https://tools.ietf.org/html/rfc952">RFC952</a>. It must satisfy the following constraints.</p>
<ul>
<li>Up to 24 characters</li>
<li>Only the alphabet (a-z, A-Z), digits (0-9), minus sign (-)</li>
<h3id="ticker-for-wifi-status"><iclass="fa fa-caret-right"></i> Ticker for WiFi status<aclass="headerlink"href="#ticker-for-wifi-status"title="Permanent link">¶</a></h3>
<p>Flicker signal can be output from the ESP8266/ESP32 module according to WiFi connection status. If you connect the LED to the signal output pin, you can know the WiFi connection status during behavior inside AutoConnect::begin through the LED blink.</p>
<p><ahref="apiconfig.html#ticker">AutoConnectConfig::ticker</a> option specifies flicker signal output. The following sketch is an example of flashing the active-high LED connected to pin #16 according to WiFi connection during the AutoConnect::begin.</p>
<p><ahref="apiconfig.html#tickerport">AutoConnectConfig::tickerPort</a> specifies a port that outputs the flicker signal. If you are using an LED-equipped ESP module board, you can assign a LED pin to the tick-port for the WiFi connection monitoring without the external LED. The default pin is arduino valiant's <strong>LED_BUILTIN</strong>. You can refer to the Arduino IDE's variant information to find out which pin actually on the module assign to <strong>LED_BUILTIN</strong>.<supid="fnref:3"><aclass="footnote-ref"href="#fn:3"rel="footnote">3</a></sup></p>
<p><ahref="apiconfig.html#tickeron">AutoConnectConfig::tickerOn</a> specifies the active logic level of the flicker signal. This value indicates the active signal level when driving the ticker. For example, if the LED connected to tickPort lights by LOW, the tickerOn is <strong>LOW</strong>. The logic level of LED_BUILTIN for popular modules are as follows:</p>
<p>The source code placement of common macros for AutoConnect since v0.9.7 has changed. <aclass="footnote-backref"href="#fnref:1"rev="footnote"title="Jump back to footnote 1 in the text">↩</a></p>
</li>
<liid="fn:2">
<p>Static IP address assignment is available from version 0.9.3. <aclass="footnote-backref"href="#fnref:2"rev="footnote"title="Jump back to footnote 2 in the text">↩</a></p>
<p>It's defined in the <code>pins_arduino.h</code> file, located in the sub-folder named <strong>variants</strong> wherein Arduino IDE installed folder. <aclass="footnote-backref"href="#fnref:3"rev="footnote"title="Jump back to footnote 3 in the text">↩</a></p>
