Merge pull request #375 from pennam/docs_update

README update

Author: pennam

README.md

@@ -10,11 +10,11 @@
 ### What?
 The `ArduinoIoTCloud` library is the central element of the firmware enabling certain Arduino boards to connect to the [Arduino IoT Cloud](https://www.arduino.cc/en/IoT/HomePage). The following boards are supported:
 
-* **WiFi**: [`MKR 1000`](https://store.arduino.cc/arduino-mkr1000-wifi), [`MKR WiFi 1010`](https://store.arduino.cc/arduino-mkr-wifi-1010), [`Nano 33 IoT`](https://store.arduino.cc/arduino-nano-33-iot), [`Portenta H7`](https://store.arduino.cc/portenta-h7), [`Nano RP2040 Connect`](https://store.arduino.cc/products/arduino-nano-rp2040-connect), [`Nicla Vision`](https://store.arduino.cc/products/nicla-vision), [`ESP8266`](https://github.com/esp8266/Arduino/releases/tag/2.5.0), [`ESP32`](https://github.com/espressif/arduino-esp32/releases/tag/1.0.6)
+* **WiFi**: [`MKR 1000`](https://store.arduino.cc/arduino-mkr1000-wifi), [`MKR WiFi 1010`](https://store.arduino.cc/arduino-mkr-wifi-1010), [`Nano 33 IoT`](https://store.arduino.cc/arduino-nano-33-iot), [`Portenta H7`](https://store.arduino.cc/portenta-h7), [`Nano RP2040 Connect`](https://store.arduino.cc/products/arduino-nano-rp2040-connect), [`Nicla Vision`](https://store.arduino.cc/products/nicla-vision), [`OPTA WiFi`](https://store.arduino.cc/products/opta-wifi), [`GIGA R1 WiFi`](https://store.arduino.cc/products/giga-r1-wifi), [`Portenta C33`](https://store.arduino.cc/products/portenta-c33), [`UNO R4 WiFi`](https://store.arduino.cc/products/uno-r4-wifi), [`Nano ESP32`](https://store.arduino.cc/products/nano-esp32), [`ESP8266`](https://github.com/esp8266/Arduino/releases/tag/2.5.0), [`ESP32`](https://github.com/espressif/arduino-esp32/releases/tag/2.0.5)
 * **GSM**: [`MKR GSM 1400`](https://store.arduino.cc/arduino-mkr-gsm-1400-1415)
 * **5G**: [`MKR NB 1500`](https://store.arduino.cc/arduino-mkr-nb-1500-1413)
 * **LoRa**: [`MKR WAN 1300/1310`](https://store.arduino.cc/mkr-wan-1310)
-* **Ethernet**: [`Portenta H7`](https://store.arduino.cc/products/portenta-h7) + [`Vision Shield Ethernet`](https://store.arduino.cc/products/arduino-portenta-vision-shield-ethernet), [`Max Carrier`](https://store.arduino.cc/products/portenta-max-carrier), [`Breakout`](https://store.arduino.cc/products/arduino-portenta-breakout), [`Portenta Machine Control`](https://store.arduino.cc/products/arduino-portenta-machine-control)
+* **Ethernet**: [`Portenta H7`](https://store.arduino.cc/products/portenta-h7) + [`Vision Shield Ethernet`](https://store.arduino.cc/products/arduino-portenta-vision-shield-ethernet), [`Max Carrier`](https://store.arduino.cc/products/portenta-max-carrier), [`Breakout`](https://store.arduino.cc/products/arduino-portenta-breakout), [`Portenta Machine Control`](https://store.arduino.cc/products/arduino-portenta-machine-control), [`OPTA WiFi`](https://store.arduino.cc/products/opta-wifi), [`OPTA RS485`](https://store.arduino.cc/products/opta-rs485), [`OPTA Lite`](https://store.arduino.cc/products/opta-lite), [`Portenta C33`](https://store.arduino.cc/products/portenta-c33) + [`Vision Shield Ethernet`](https://store.arduino.cc/products/arduino-portenta-vision-shield-ethernet)
 
 ### How?
 1) Register your Arduino IoT Cloud capable board via [Arduino IoT Cloud](https://create.arduino.cc/iot) (Devices Section).
@@ -75,6 +75,8 @@ The [1.0.0](https://github.com/arduino-libraries/ArduinoIoTCloud/releases/tag/1.
 ArduinoCloud.begin(ArduinoIoTPreferredConnection, false).
 ```
 
+Whatchdog is enabled by default using the following boards: [`MKR 1000`](https://store.arduino.cc/arduino-mkr1000-wifi), [`MKR WiFi 1010`](https://store.arduino.cc/arduino-mkr-wifi-1010), [`MKR GSM 1400`](https://store.arduino.cc/arduino-mkr-gsm-1400-1415), [`MKR NB 1500`](https://store.arduino.cc/arduino-mkr-nb-1500-1413), [`MKR WAN 1300/1310`](https://store.arduino.cc/mkr-wan-1310), [`Nano 33 IoT`](https://store.arduino.cc/arduino-nano-33-iot), [`Portenta H7`](https://store.arduino.cc/portenta-h7), [`Nano RP2040 Connect`](https://store.arduino.cc/products/arduino-nano-rp2040-connect), [`Nicla Vision`](https://store.arduino.cc/products/nicla-vision), [`OPTA WiFi`](https://store.arduino.cc/products/opta-wifi), [`OPTA RS485`](https://store.arduino.cc/products/opta-rs485), [`OPTA Lite`](https://store.arduino.cc/products/opta-lite), [`GIGA R1 WiFi`](https://store.arduino.cc/products/giga-r1-wifi)
+
 #### Device can not subscribe to `THING_ID`
 ```
 ArduinoIoTCloudTCP::handle_SubscribeMqttTopics could not subscribe to /a/t/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/e/i
@@ -83,11 +85,15 @@ In this case either the device has not been associated with the thing within the
 
 #### OTA
 OTA is supported by the following boards:
-[`MKR WiFi 1010`](https://store.arduino.cc/arduino-mkr-wifi-1010), [`Nano 33 IoT`](https://store.arduino.cc/arduino-nano-33-iot), [`Portenta H7`](https://store.arduino.cc/portenta-h7), [`Nano RP2040 Connect`](https://store.arduino.cc/products/arduino-nano-rp2040-connect), [`Nicla Vision`](https://store.arduino.cc/products/nicla-vision)
+[`MKR WiFi 1010`](https://store.arduino.cc/arduino-mkr-wifi-1010), [`Nano 33 IoT`](https://store.arduino.cc/arduino-nano-33-iot), [`Portenta H7`](https://store.arduino.cc/portenta-h7), [`Nano RP2040 Connect`](https://store.arduino.cc/products/arduino-nano-rp2040-connect), [`Nicla Vision`](https://store.arduino.cc/products/nicla-vision), [`OPTA WiFi`](https://store.arduino.cc/products/opta-wifi), [`OPTA RS485`](https://store.arduino.cc/products/opta-rs485), [`OPTA Lite`](https://store.arduino.cc/products/opta-lite), [`GIGA R1 WiFi`](https://store.arduino.cc/products/giga-r1-wifi), [`Nano ESP32`](https://store.arduino.cc/products/nano-esp32), [`ESP32`](https://github.com/espressif/arduino-esp32/releases/tag/2.0.5)
+
+#### Authentication
+Boards can authenticate to the ArduinoIoTCloud servers using 3 methods:
+
+ * `DEVICE_LOGIN_NAME` and `DEVICE_KEY`. This values are defined in the `thingProperties.h` file and included in the Sketch. Boards that are using this method are: [`UNO R4 WiFi`](https://store.arduino.cc/products/uno-r4-wifi), [`Nano ESP32`](https://store.arduino.cc/products/nano-esp32), [`ESP8266`](https://github.com/esp8266/Arduino/releases/tag/2.5.0), [`ESP32`](https://github.com/espressif/arduino-esp32/releases/tag/2.0.5)
+
+ * `DEVICE_CERTIFICATE` and `PRIVATE_KEY`. This values are stored inside the board secure element during the device provisioning phase. Boards that are using this method are: [`MKR 1000`](https://store.arduino.cc/arduino-mkr1000-wifi), [`MKR WiFi 1010`](https://store.arduino.cc/arduino-mkr-wifi-1010), [`MKR GSM 1400`](https://store.arduino.cc/arduino-mkr-gsm-1400-1415), [`MKR NB 1500`](https://store.arduino.cc/arduino-mkr-nb-1500-1413), [`Nano 33 IoT`](https://store.arduino.cc/arduino-nano-33-iot), [`Portenta H7`](https://store.arduino.cc/portenta-h7), [`Nano RP2040 Connect`](https://store.arduino.cc/products/arduino-nano-rp2040-connect), [`Nicla Vision`](https://store.arduino.cc/products/nicla-vision), [`OPTA WiFi`](https://store.arduino.cc/products/opta-wifi), [`OPTA RS485`](https://store.arduino.cc/products/opta-rs485), [`OPTA Lite`](https://store.arduino.cc/products/opta-lite), [`GIGA R1 WiFi`](https://store.arduino.cc/products/giga-r1-wifi), [`Portenta C33`](https://store.arduino.cc/products/portenta-c33)
 
-#### ESP Boards
-Support for ESP boards is obtained through a third-party core with some differences and limitations compared to Arduino boards.
+ * `APP_EUI` and `APP_KEY`. This values are defined in the `thingProperties.h` file and included in the Sketch. Boards that are using this method are: [`MKR WAN 1300/1310`](https://store.arduino.cc/mkr-wan-1310)
 
-- **Authentication scheme**: Board authentication is done through `DEVICE_LOGIN_NAME` and `DEVICE_KEY`, both values are included in the `thingProperties.h` file.
-- **Watchdog**: Watchdog support is not included.
-- **OTA**: OTA support is not included
+