![\"esp32-ota-web-updates\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/OTAWebUpdates_ESP32_thumbnail.jpg?resize=1200%2C675&quality=100&strip=all&ssl=1\")
<\/p>\nQuick guide that shows how to do over-the-air (OTA) programming with the ESP32 using the OTA Web Updater in Arduino IDE.\u00a0The OTA Web Updater allows you to update\/upload new code to your ESP32 using a browser, without the need to make a serial connection between the ESP32 and your computer.<\/p>\n
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OTA programming is useful when you need to update code to ESP32 boards that are not easily accessible. The example we\u2019ll show here works when the ESP32 and your browser are on your local network.<\/p>\n
The only disadvantage of the OTA Web Updater is that you have to add the code for OTA in every sketch you upload, so that you’re able to use OTA in the future.<\/p>\n
Before proceeding with this tutorial you should have the ESP32 add-on installed in your Arduino IDE. Follow one of the next tutorials to install the ESP32 on the Arduino IDE, if you haven\u2019t already.<\/span><\/p>\n When you install the ESP32 add-on for the Arduino IDE, it will automatically install the ArduinoOTA library. Go to File<\/strong> > Examples<\/strong> >ArduinoOTA<\/strong>> OTAWebUpdater<\/strong>.<\/p>\n The following code should load.<\/p>\n View raw code<\/a><\/p>\n You should change the following lines on the code to include your own network credentials:<\/p>\n The OTAWebUpdater example for the ESP32 creates an asynchronous web server where you can upload new code to your board without the need for a serial connection.<\/p>\n Upload the previous code to your ESP32 board. Don\u2019t forget to enter your network credentials and select the right board and serial port.<\/p>\n After uploading the code, open the Serial Monitor at a baud rate of 115200, press the ESP32 enable button, and you should get the ESP32 IP address:<\/p>\n Now, you can upload code to your ESP32 over-the-air using a browser on your local network.<\/p>\n To test the OTA Web Updater you can disconnect the ESP32 from your computer and power it using a power bank, for example (this is optional, we’re suggesting this to mimic a situation in which the ESP32 is not connected to your computer).<\/p>\n Open a browser in your network and enter the ESP32 IP address. You should get the following:<\/p>\n Enter the username and the password:<\/p>\n You can change the username and password on the code.<\/p>\n Note:\u00a0<\/strong>After you enter the username and password, you are redirected to the \/serverIndex<\/em> URL. You don’t need to enter the username and password to access the \/serverIndex<\/em> URL. So, if someone knows the URL to upload new code, the username and password don’t protect the web page from being accessible from others.<\/p>\n A new tab should open on the \/serverIndex<\/em> URL. This page allows you to upload a new code to your ESP32. You should upload .bin<\/em> files (we’ll see how to do that in a moment).<\/p>\n When uploading a new sketch over-the-air, you need to keep in mind that you need to add code for OTA in your new sketch, so that you can\u00a0always overwrite any sketch with a new one in the future. So, we recommend that you modify the\u00a0OTAWebUpdater sketch to include your own code.<\/p>\n For learning purposes let’s upload a new code that blinks an LED (without delay). Copy the following code to your Arduino IDE.<\/p>\n View raw code<\/a><\/p>\n As you can see, we’ve added the “blink without delay” code to the OTAWebUpdater code, so that we’re able to make updates later on.<\/p>\n After copying the code to your Arduino IDE, you should generate a .bin<\/em> file.<\/p>\n Save your sketch as LED_Web_Updater<\/em>.<\/p>\n To generate a .bin<\/em> file from your sketch, go to Sketch<\/strong> > Export compiled Binary<\/strong><\/p>\n A new file on the folder sketch should be created. Go to Sketch<\/strong> > Show Sketch<\/strong> Folder<\/strong>. You should have two files in your Sketch folder: the .ino<\/em> and the .bin<\/em> file. You should upload the .bin<\/em> file using the OTA Web Updater.<\/p>\n In your browser, on the ESP32 OTA Web Updater page, click the Choose File<\/strong> button. Select the .bin<\/em> file generated previously, and then click Update<\/strong>.<\/p>\n After a few seconds, the code should be successfully uploaded.<\/p>\n The ESP32 built-in LED should be blinking.<\/p>\n Congratulations! You’ve uploaded a new code to your ESP32 over-the-air.<\/p>\n Over-the-air updates are useful to upload new code to your ESP32 board when it is not easily accessible. The OTA Web Updater code creates a web server that you can access to upload new code to your ESP32 board using a web browser on your local network.<\/p>\n We hope you’ve found this article interesting. If you like ESP32 you may also like:<\/p>\n Quick guide that shows how to do over-the-air (OTA) programming with the ESP32 using the OTA Web Updater in Arduino IDE.\u00a0The OTA Web Updater allows you to update\/upload new code … <\/p>\n\n
ESP32 OTA Web Updater<\/h2>\n
![\"otawebupdater-arduino-ide\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/OTAwebupdater_example.png?resize=565%2C594&quality=100&strip=all&ssl=1\")
<\/p>\n\/*\n * OTAWebUpdater.ino Example from ArduinoOTA Library\n * Rui Santos \n * Complete Project Details http:\/\/randomnerdtutorials.com\n *\/\n\n#include <WiFi.h>\n#include <WiFiClient.h>\n#include <WebServer.h>\n#include <ESPmDNS.h>\n#include <Update.h>\n\nconst char* host = "esp32";\nconst char* ssid = "REPLACE_WITH_YOUR_SSID";\nconst char* password = "REPLACE_WITH_YOUR_PASSWORD";\n\nWebServer server(80);\n\n\/*\n * Login page\n *\/\nconst char* loginIndex = \n "<form name='loginForm'>"\n "<table width='20%' bgcolor='A09F9F' align='center'>"\n "<tr>"\n "<td colspan=2>"\n "<center><font size=4><b>ESP32 Login Page<\/b><\/font><\/center>"\n "<br>"\n "<\/td>"\n "<br>"\n "<br>"\n "<\/tr>"\n "<td>Username:<\/td>"\n "<td><input type='text' size=25 name='userid'><br><\/td>"\n "<\/tr>"\n "<br>"\n "<br>"\n "<tr>"\n "<td>Password:<\/td>"\n "<td><input type='Password' size=25 name='pwd'><br><\/td>"\n "<br>"\n "<br>"\n "<\/tr>"\n "<tr>"\n "<td><input type='submit' onclick='check(this.form)' value='Login'><\/td>"\n "<\/tr>"\n "<\/table>"\n"<\/form>"\n"<script>"\n "function check(form)"\n "{"\n "if(form.userid.value=='admin' && form.pwd.value=='admin')"\n "{"\n "window.open('\/serverIndex')"\n "}"\n "else"\n "{"\n " alert('Error Password or Username')\/*displays error message*\/"\n "}"\n "}"\n"<\/script>";\n \n\/*\n * Server Index Page\n *\/\n \nconst char* serverIndex = \n"<script src='https:\/\/ajax.googleapis.com\/ajax\/libs\/jquery\/3.2.1\/jquery.min.js'><\/script>"\n"<form method='POST' action='#' enctype='multipart\/form-data' id='upload_form'>"\n "<input type='file' name='update'>"\n "<input type='submit' value='Update'>"\n "<\/form>"\n "<div id='prg'>progress: 0%<\/div>"\n "<script>"\n "$('form').submit(function(e){"\n "e.preventDefault();"\n "var form = $('#upload_form')[0];"\n "var data = new FormData(form);"\n " $.ajax({"\n "url: '\/update',"\n "type: 'POST',"\n "data: data,"\n "contentType: false,"\n "processData:false,"\n "xhr: function() {"\n "var xhr = new window.XMLHttpRequest();"\n "xhr.upload.addEventListener('progress', function(evt) {"\n "if (evt.lengthComputable) {"\n "var per = evt.loaded \/ evt.total;"\n "$('#prg').html('progress: ' + Math.round(per*100) + '%');"\n "}"\n "}, false);"\n "return xhr;"\n "},"\n "success:function(d, s) {"\n "console.log('success!')" \n "},"\n "error: function (a, b, c) {"\n "}"\n "});"\n "});"\n "<\/script>";\n\n\/*\n * setup function\n *\/\nvoid setup(void) {\n Serial.begin(115200);\n\n \/\/ Connect to WiFi network\n WiFi.begin(ssid, password);\n Serial.println("");\n\n \/\/ Wait for connection\n while (WiFi.status() != WL_CONNECTED) {\n delay(500);\n Serial.print(".");\n }\n Serial.println("");\n Serial.print("Connected to ");\n Serial.println(ssid);\n Serial.print("IP address: ");\n Serial.println(WiFi.localIP());\n\n \/*use mdns for host name resolution*\/\n if (!MDNS.begin(host)) { \/\/http:\/\/esp32.local\n Serial.println("Error setting up MDNS responder!");\n while (1) {\n delay(1000);\n }\n }\n Serial.println("mDNS responder started");\n \/*return index page which is stored in serverIndex *\/\n server.on("\/", HTTP_GET, []() {\n server.sendHeader("Connection", "close");\n server.send(200, "text\/html", loginIndex);\n });\n server.on("\/serverIndex", HTTP_GET, []() {\n server.sendHeader("Connection", "close");\n server.send(200, "text\/html", serverIndex);\n });\n \/*handling uploading firmware file *\/\n server.on("\/update", HTTP_POST, []() {\n server.sendHeader("Connection", "close");\n server.send(200, "text\/plain", (Update.hasError()) ? "FAIL" : "OK");\n ESP.restart();\n }, []() {\n HTTPUpload& upload = server.upload();\n if (upload.status == UPLOAD_FILE_START) {\n Serial.printf("Update: %s\\n", upload.filename.c_str());\n if (!Update.begin(UPDATE_SIZE_UNKNOWN)) { \/\/start with max available size\n Update.printError(Serial);\n }\n } else if (upload.status == UPLOAD_FILE_WRITE) {\n \/* flashing firmware to ESP*\/\n if (Update.write(upload.buf, upload.currentSize) != upload.currentSize) {\n Update.printError(Serial);\n }\n } else if (upload.status == UPLOAD_FILE_END) {\n if (Update.end(true)) { \/\/true to set the size to the current progress\n Serial.printf("Update Success: %u\\nRebooting...\\n", upload.totalSize);\n } else {\n Update.printError(Serial);\n }\n }\n });\n server.begin();\n}\n\nvoid loop(void) {\n server.handleClient();\n delay(1);\n}\n<\/code><\/pre>\n\tconst char* ssid = \"\";\nconst char* password = \"\";<\/pre>\n
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/12\/arduino-ide-upload-button.png?resize=34%2C29&quality=100&strip=all&ssl=1\")
<\/p>\n![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/IP-address.jpg?resize=632%2C390&quality=100&strip=all&ssl=1\")
<\/p>\nUpdate New Code using OTA Web Updater<\/h2>\n
![\"otawebupdater-user-pass\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/esp32-login-page.jpg?resize=667%2C396&quality=100&strip=all&ssl=1\")
<\/p>\n\n
![\"ota-web-updater-esp32\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/serverindex.jpg?resize=621%2C333&quality=100&strip=all&ssl=1\")
<\/p>\nPreparing the New Sketch<\/h2>\n
\/*\n * Rui Santos \n * Complete Project Details http:\/\/randomnerdtutorials.com\n *\/\n\n#include <WiFi.h>\n#include <WiFiClient.h>\n#include <WebServer.h>\n#include <ESPmDNS.h>\n#include <Update.h>\n\nconst char* host = "esp32";\nconst char* ssid = "REPLACE_WITH_YOUR_SSID";\nconst char* password = "REPLACE_WITH_YOUR_PASSWORD";\n\n\/\/variabls to blink without delay:\nconst int led = 2;\nunsigned long previousMillis = 0; \/\/ will store last time LED was updated\nconst long interval = 1000; \/\/ interval at which to blink (milliseconds)\nint ledState = LOW; \/\/ ledState used to set the LED\n\nWebServer server(80);\n\n\/*\n * Login page\n *\/\n\nconst char* loginIndex = \n "<form name='loginForm'>"\n "<table width='20%' bgcolor='A09F9F' align='center'>"\n "<tr>"\n "<td colspan=2>"\n "<center><font size=4><b>ESP32 Login Page<\/b><\/font><\/center>"\n "<br>"\n "<\/td>"\n "<br>"\n "<br>"\n "<\/tr>"\n "<td>Username:<\/td>"\n "<td><input type='text' size=25 name='userid'><br><\/td>"\n "<\/tr>"\n "<br>"\n "<br>"\n "<tr>"\n "<td>Password:<\/td>"\n "<td><input type='Password' size=25 name='pwd'><br><\/td>"\n "<br>"\n "<br>"\n "<\/tr>"\n "<tr>"\n "<td><input type='submit' onclick='check(this.form)' value='Login'><\/td>"\n "<\/tr>"\n "<\/table>"\n"<\/form>"\n"<script>"\n "function check(form)"\n "{"\n "if(form.userid.value=='admin' && form.pwd.value=='admin')"\n "{"\n "window.open('\/serverIndex')"\n "}"\n "else"\n "{"\n " alert('Error Password or Username')\/*displays error message*\/"\n "}"\n "}"\n"<\/script>";\n \n\/*\n * Server Index Page\n *\/\n \nconst char* serverIndex = \n"<script src='https:\/\/ajax.googleapis.com\/ajax\/libs\/jquery\/3.2.1\/jquery.min.js'><\/script>"\n"<form method='POST' action='#' enctype='multipart\/form-data' id='upload_form'>"\n "<input type='file' name='update'>"\n "<input type='submit' value='Update'>"\n "<\/form>"\n "<div id='prg'>progress: 0%<\/div>"\n "<script>"\n "$('form').submit(function(e){"\n "e.preventDefault();"\n "var form = $('#upload_form')[0];"\n "var data = new FormData(form);"\n " $.ajax({"\n "url: '\/update',"\n "type: 'POST',"\n "data: data,"\n "contentType: false,"\n "processData:false,"\n "xhr: function() {"\n "var xhr = new window.XMLHttpRequest();"\n "xhr.upload.addEventListener('progress', function(evt) {"\n "if (evt.lengthComputable) {"\n "var per = evt.loaded \/ evt.total;"\n "$('#prg').html('progress: ' + Math.round(per*100) + '%');"\n "}"\n "}, false);"\n "return xhr;"\n "},"\n "success:function(d, s) {"\n "console.log('success!')" \n "},"\n "error: function (a, b, c) {"\n "}"\n "});"\n "});"\n "<\/script>";\n\n\/*\n * setup function\n *\/\nvoid setup(void) {\n pinMode(led, OUTPUT);\n \n Serial.begin(115200);\n\n \/\/ Connect to WiFi network\n WiFi.begin(ssid, password);\n Serial.println("");\n\n \/\/ Wait for connection\n while (WiFi.status() != WL_CONNECTED) {\n delay(500);\n Serial.print(".");\n }\n Serial.println("");\n Serial.print("Connected to ");\n Serial.println(ssid);\n Serial.print("IP address: ");\n Serial.println(WiFi.localIP());\n\n \/*use mdns for host name resolution*\/\n if (!MDNS.begin(host)) { \/\/http:\/\/esp32.local\n Serial.println("Error setting up MDNS responder!");\n while (1) {\n delay(1000);\n }\n }\n Serial.println("mDNS responder started");\n \/*return index page which is stored in serverIndex *\/\n server.on("\/", HTTP_GET, []() {\n server.sendHeader("Connection", "close");\n server.send(200, "text\/html", loginIndex);\n });\n server.on("\/serverIndex", HTTP_GET, []() {\n server.sendHeader("Connection", "close");\n server.send(200, "text\/html", serverIndex);\n });\n \/*handling uploading firmware file *\/\n server.on("\/update", HTTP_POST, []() {\n server.sendHeader("Connection", "close");\n server.send(200, "text\/plain", (Update.hasError()) ? "FAIL" : "OK");\n ESP.restart();\n }, []() {\n HTTPUpload& upload = server.upload();\n if (upload.status == UPLOAD_FILE_START) {\n Serial.printf("Update: %s\\n", upload.filename.c_str());\n if (!Update.begin(UPDATE_SIZE_UNKNOWN)) { \/\/start with max available size\n Update.printError(Serial);\n }\n } else if (upload.status == UPLOAD_FILE_WRITE) {\n \/* flashing firmware to ESP*\/\n if (Update.write(upload.buf, upload.currentSize) != upload.currentSize) {\n Update.printError(Serial);\n }\n } else if (upload.status == UPLOAD_FILE_END) {\n if (Update.end(true)) { \/\/true to set the size to the current progress\n Serial.printf("Update Success: %u\\nRebooting...\\n", upload.totalSize);\n } else {\n Update.printError(Serial);\n }\n }\n });\n server.begin();\n}\n\nvoid loop(void) {\n server.handleClient();\n delay(1);\n\n \/\/loop to blink without delay\n unsigned long currentMillis = millis();\n\n if (currentMillis - previousMillis >= interval) {\n \/\/ save the last time you blinked the LED\n previousMillis = currentMillis;\n\n \/\/ if the LED is off turn it on and vice-versa:\n ledState = not(ledState);\n\n \/\/ set the LED with the ledState of the variable:\n digitalWrite(led, ledState);\n }\n}\n<\/code><\/pre>\n\tGenerate a .bin file in Arduino IDE<\/h3>\n
![\"export-bin-file-arduino-ide\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/export-binary-file-arduino-ide.png?resize=651%2C231&quality=100&strip=all&ssl=1\")
<\/p>\n![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/bin-file-folder.jpg?resize=343%2C197&quality=100&strip=all&ssl=1\")
<\/p>\nUpload a new sketch over-the-air to the ESP32<\/h3>\n
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/bin-file-uploaded.jpg?resize=702%2C244&quality=100&strip=all&ssl=1\")
<\/p>\n![\"esp32-blinking-led\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2018\/11\/DSC01830.jpg?resize=800%2C622&quality=100&strip=all&ssl=1\")
<\/p>\nWrapping Up<\/h2>\n
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