feat(BLE): Update Notify.ino

Improve Notify.ino example by adding the 0x2901 descriptor

This also prevents and helps to find issues when testing CI.

Author: SuGlider

libraries/BLE/examples/Notify/Notify.ino

@@ -23,18 +23,21 @@
 #include <BLEServer.h>
 #include <BLEUtils.h>
 #include <BLE2902.h>
+#include <BLE2901.h>
 
 BLEServer *pServer = NULL;
 BLECharacteristic *pCharacteristic = NULL;
+BLE2901 *descriptor_2901 = NULL;
+
 bool deviceConnected = false;
 bool oldDeviceConnected = false;
 uint32_t value = 0;
 
 // See the following for generating UUIDs:
 // https://www.uuidgenerator.net/
 
-#define SERVICE_UUID        "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
-#define CHARACTERISTIC_UUID "beb5483e-36e1-4688-b7f5-ea07361b26a8"
+#define SERVICE_UUID        "0000ff00-0000-1000-8000-00805f9b34fb"
+#define CHARACTERISTIC_UUID "0000ff01-0000-1000-8000-00805f9b34fb"
 
 class MyServerCallbacks : public BLEServerCallbacks {
   void onConnect(BLEServer *pServer) {
@@ -65,9 +68,13 @@ void setup() {
     BLECharacteristic::PROPERTY_READ | BLECharacteristic::PROPERTY_WRITE | BLECharacteristic::PROPERTY_NOTIFY | BLECharacteristic::PROPERTY_INDICATE
   );
 
-  // https://www.bluetooth.com/specifications/gatt/viewer?attributeXmlFile=org.bluetooth.descriptor.gatt.client_characteristic_configuration.xml
-  // Create a BLE Descriptor
+  // Creates BLE Descriptor 0x2902: Client Characteristic Configuration Descriptor (CCCD) 
   pCharacteristic->addDescriptor(new BLE2902());
+  // Adds also the Characteristic User Description - 0x2901 descriptor
+  descriptor_2901 = new BLE2901();
+  descriptor_2901->setDescription("My own description for this characteristic.");
+  descriptor_2901->setAccessPermissions(ESP_GATT_PERM_READ); // enforce read only - default is Read|Write 
+  pCharacteristic->addDescriptor(descriptor_2901);
 
   // Start the service
   pService->start();
@@ -87,7 +94,7 @@ void loop() {
     pCharacteristic->setValue((uint8_t *)&value, 4);
     pCharacteristic->notify();
     value++;
-    delay(3);  // bluetooth stack will go into congestion, if too many packets are sent, in 6 hours test i was able to go as low as 3ms
+    delay(500);
   }
   // disconnecting
   if (!deviceConnected && oldDeviceConnected) {