doc: enhance readability using alerts format

Signed-off-by: Frederic Pillon <[email protected]>

Author: fpistm

README.md

@@ -26,34 +26,40 @@ as a simple LoRa® radio module.
 
 * The module supports only class A.
 * Sleep mode is not supported in OTAA mode with the version 2.6 of the firmware.
-* Important note for Nucleo64:
-
-  By default, D0/D1 of CN9 board connector are respectively not connected to
-  PA3 and PA2 (SB62 and SB63 opened).
-  Those pins are connected to STLink USART thanks to SB13, SB14.
-
-  To use the shield:
-    - Connect shield D0(Tx) to a free U(S)ARTn Rx pin
-    - Connect shield D1(Rx) to a free U(S)ARTn Tx pin
-
-  Where 'n' are the same U(S)ART number.
-
-    - Update the Serial instance definition used for LoRa using the chosen Rx/Tx
-
-  or
-
-    - Close SB62 and SB63 to connect D0/D1 of CN9 connector to PA3 and PA2
-    - Open SB13 and SB14 to disconnect PA3 and PA2 from STLink UART
-
-  but in this case, you will have to wire STLink Rx/Tx of CN3 connector to
-  another pins and update Serial instance before call `Serial.begin(115200);`
-  using:
-  ```
-  Serial.setRx(Rx pin);
-  Serial.setTx(Tx pin);
-  ```
-  
-  See [UM1724](https://www.st.com/resource/en/user_manual/dm00105823.pdf), §6.8 section for more information.
+> [!IMPORTANT]
+> Usage with a Nucleo 64:
+>
+>  By default, D0/D1 of CN9 board connector are respectively not connected to
+>  PA3 and PA2 (SB62 and SB63 opened).
+>  Those pins are connected to STLink USART thanks to SB13, SB14.
+>
+>  To use the shield, two options:
+>  * First option:
+>     - Connect shield D0(Tx) to a free U(S)ARTn Rx pin
+>     - Connect shield D1(Rx) to a free U(S)ARTn Tx pin
+>
+>     Where 'n' are the same U(S)ART number.
+>
+>     - Update the Serial instance definition used for LoRa using the chosen Rx/Tx
+>     Example:
+>     ```c++
+>     HardwareSerial SerialLora(PC11, PC10);
+>     ```
+>
+>  * Second option:
+>
+>     - Close SB62 and SB63 to connect D0/D1 of CN9 connector to PA3 and PA2
+>     - Open SB13 and SB14 to disconnect PA3 and PA2 from STLink UART
+>
+>     but in this case, you will have to wire STLink Rx/Tx of CN3 connector to
+>     another pins and update Serial instance before call `Serial.begin(115200);`
+>     using:
+>     ```c++
+>     Serial.setRx(Rx pin);
+>     Serial.setTx(Tx pin);
+>     ```
+>
+>  See [UM1724](https://www.st.com/resource/en/user_manual/dm00105823.pdf), §6.8 section for more information.
 
 ## Examples