Add support for OTA mode.

Now you can update the ESP32RET firmware over wifi!

ESP32RET.ino

@@ -31,6 +31,9 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <SPI.h>
 #include <WiFi.h>
 #include <WiFiMulti.h>
+#include <ESPmDNS.h>
+#include <WiFiUdp.h>
+#include <ArduinoOTA.h>
 #include "ELM327_Emulator.h"
 
 #include "EEPROM.h"
@@ -997,7 +1000,7 @@ void loop()
     bool isConnected = false;
     int serialCnt;
     uint8_t in_byte;
-    boolean needServerInit = false;
+    boolean needServerInit = false;    
 
     if (settings.wifiMode > 0)
     {
@@ -1027,14 +1030,46 @@ void loop()
                 {
                     SysSettings.isWifiConnected = true;
                     wifiServer.begin();
-                    wifiServer.setNoDelay(true);
+                    wifiServer.setNoDelay(true);                    
                 }
                 else
                 {
                     Serial.println("Starting UDP Server");
                     SysSettings.isWifiConnected = true;
                     //wifiUDPServer.begin(17222);
                 }
+                ArduinoOTA.setPort(3232);
+                ArduinoOTA.setHostname("ESPRET");
+                // No authentication by default
+                //ArduinoOTA.setPassword("admin");
+
+                ArduinoOTA
+                   .onStart([]() {
+                      String type;
+                      if (ArduinoOTA.getCommand() == U_FLASH)
+                         type = "sketch";
+                      else // U_SPIFFS
+                         type = "filesystem";
+
+                      // NOTE: if updating SPIFFS this would be the place to unmount SPIFFS using SPIFFS.end()
+                      Serial.println("Start updating " + type);
+                   })
+                   .onEnd([]() {
+                      Serial.println("\nEnd");
+                   })
+                   .onProgress([](unsigned int progress, unsigned int total) {
+                       Serial.printf("Progress: %u%%\r", (progress / (total / 100)));
+                   })
+                   .onError([](ota_error_t error) {
+                      Serial.printf("Error[%u]: ", error);
+                      if (error == OTA_AUTH_ERROR) Serial.println("Auth Failed");
+                      else if (error == OTA_BEGIN_ERROR) Serial.println("Begin Failed");
+                      else if (error == OTA_CONNECT_ERROR) Serial.println("Connect Failed");
+                      else if (error == OTA_RECEIVE_ERROR) Serial.println("Receive Failed");
+                      else if (error == OTA_END_ERROR) Serial.println("End Failed");
+                   });
+
+                ArduinoOTA.begin();
             }
         }
         else
@@ -1238,5 +1273,6 @@ void loop()
 
     Logger::loop();
     //elmEmulator.loop();
+    ArduinoOTA.handle();
 }