 };
 
 void loop() {
-  // Examples for AT commands
+  // Execute AT commands step by step
   unsigned long currentMillis = millis();
   if (currentMillis - previousMillis >= interval) {
     previousMillis = currentMillis;
     switch (i) {
       case 0:
         // Must reset for change role
+        // Change to central role
         ble.setRole(BLEPAD_MASTER_MODE);
         ble.write("<RESET>");
         break;
       case 1:
+        // Query the ROLE type, it should show central
         ble.write("<ROLETYPE>");
         break;
       case 2:

    i++;
  }

  while (ble.available() > 0)  {
    tmp += char(ble.read());
    delay(2);

/*
 * Central role example
 */
 
#include "BLEPad_UART.h"
