Clarified useage of SPP example

Author: PilnyTomas

libraries/BluetoothSerial/examples/SerialToSerialBT_SSP/SerialToSerialBT_SSP.ino

@@ -5,16 +5,26 @@
 // and also demonstrate that SerialBT have the same functionalities of a normal Serial
 // SSP - Simple Secure Pairing - The device (ESP32) will display random number and the user is responsible of comparing it to the number
 // displayed on the other device (for example phone).
-// If the numbers match the user authenticates the pairing.
+// If the numbers match the user authenticates the pairing on both devices - on phone simply press "Pair" and in terminal for the sketch send 'Y' or 'y' to confirm.
+// Alternatively uncomment AUTO_PAIR to skip the terminal confirmation.
 
 #include "BluetoothSerial.h"
 
+//#define AUTO_PAIR // Uncomment to skip the terminal confirmation.
+
+// Check if BlueTooth is available
 #if !defined(CONFIG_BT_ENABLED) || !defined(CONFIG_BLUEDROID_ENABLED)
-#error Bluetooth is not enabled! Please run `make menuconfig` to and enable it
+  #error Bluetooth is not enabled! Please run `make menuconfig` to and enable it
 #endif
 
+// Check Serial Port Profile
 #if !defined(CONFIG_BT_SPP_ENABLED)
-#error Serial Bluetooth not available or not enabled. It is only available for the ESP32 chip.
+  #error Serial Port Profile for BlueTooth is not available or not enabled. It is only available for the ESP32 chip.
+#endif
+
+// Check Simple Secure Pairing
+#if !defined(CONFIG_BT_SSP_ENABLED)
+  #error Simple Secure Pairing for BlueTooth is not available or not enabled.
 #endif
 
 const char * deviceName = "ESP32_SSP_example";
@@ -25,7 +35,11 @@ boolean confirmRequestPending = true;
 void BTConfirmRequestCallback(uint32_t numVal)
 {
   confirmRequestPending = true;
-  Serial.printf("The PIN is: %lu\n", numVal);
+#ifndef AUTO_PAIR
+  Serial.printf("The PIN is: %lu. If it matches number displayed on the other device write \'Y\' or \'y\':\n", numVal);
+#else
+  SerialBT.confirmReply(true);
+#endif
 }
 
 void BTAuthCompleteCallback(boolean success)
@@ -41,19 +55,36 @@ void BTAuthCompleteCallback(boolean success)
   }
 }
 
+void serial_response(){
+  if (Serial.available())
+    {
+      SerialBT.write(Serial.read());
+    }
+    if (SerialBT.available())
+    {
+      Serial.write(SerialBT.read());
+    }
+    delay(20);
+}
 
 void setup()
 {
   Serial.begin(115200);
   SerialBT.enableSSP();
+  SerialBT.dropCache();
   SerialBT.onConfirmRequest(BTConfirmRequestCallback);
   SerialBT.onAuthComplete(BTAuthCompleteCallback);
   SerialBT.begin(deviceName); //Bluetooth device name
-  Serial.printf("The device started with name \"%s\", now you can pair it with Bluetooth!\n", deviceName);
+#ifndef AUTO_PAIR
+  Serial.printf("The device started with name \"%s\", now you can pair it with Bluetooth!\nIf the numbers in terminal and on the other device match, press \"Pair\" in phone/computer and write \'Y\' or \'y\' in terminal\n", deviceName);
+#else
+  Serial.printf("The device started with name \"%s\", now you can pair it with Bluetooth!\nIf the numbers in terminal and on the other device match, press \"Pair\" in phone/computer.\n", deviceName);
+#endif
 }
 
 void loop()
 {
+#ifndef AUTO_PAIR
   if (confirmRequestPending)
   {
     if (Serial.available())
@@ -71,14 +102,9 @@ void loop()
   }
   else
   {
-    if (Serial.available())
-    {
-      SerialBT.write(Serial.read());
-    }
-    if (SerialBT.available())
-    {
-      Serial.write(SerialBT.read());
-    }
-    delay(20);
+    serial_response();
   }
+#else
+  serial_response();
+#endif
 }