Clarify usage of UART mode

Author: sebromero

examples/UARTRead/UARTRead.ino

@@ -1,19 +1,26 @@
 /**
  * This example shows how to read data from the UART port on the board.
- * It is meant to run on a board only connected through UART to the Nicla Sense Env.
- * This requires the Nicla Sense Env to be powered through the VIN pin or through 
- * the ESLOV connector of a host board.
- * You will need to connect the UART pins of the Nicla Sense Env to the UART pins of the board.
+ * It is meant to run on a board ONLY connected through UART to the Nicla Sense Env.
+ * Boards that have an available I2C interface can connect to the Nicla Sense Env over I2C and read the data
+ * in a much more efficient way.
+ * 
+ * A UART-only scenario requires the Nicla Sense Env to be powered through the VIN pin
+ * as it won't be powered through the ESLOV connector.
+ * You will need to connect the UART pins of the Nicla Sense Env to the UART pins of the host board.
  * On many Arduino boards the serial interface associated with those pins is Serial1.
  * Please check the documentation of your board to find out which serial interface to use.
  * 
- * UART output needs to be enabled on the Nicla Sense Env for this example to work.
- * You can do so by connecting to the board over I2C to a host board, and running the following code:
+ * IMPORTANT: UART output needs to be enabled beforehand on the Nicla Sense Env for this example to work.
+ * You will need an I2C capable board to do so.
+ * Connect Nicla Sense Env over I2C to that host board, and run the following code:
  * 
  * NiclaSenseEnv device;
- * device.begin();
- * The second parameter ensures that the settings are not lost after a reset
- * device.setUARTCSVOutputEnabled(true, true);
+ * device.begin(); 
+ * device.setUARTCSVOutputEnabled(true, true); // Second parameter ensures that the settings are not lost after a reset
+ * 
+ * After that you can disconnect the Nicla Sense Env from the I2C host board and connect it to the UART host board.
+ * You won't need to run the above code again, as the settings are stored permanently.
+ * The code below is meant to run on the UART-only host board once the UART output is enabled.
  * 
  * Initial author: Sebastian Romero (s.romero@arduino.cc)
  *