BLE low power mode and settings optimization (#902)

* BLE low power mode and settings optimization
-low power mode settings example
-take into account parameters following #891
-add esp32dev-ble-cont for door/window sensor listening

* Disable WDT during scan

* update esp32 arduino framework

main/ZgatewayBT.ino

@@ -617,19 +617,20 @@ class MyAdvertisedDeviceCallbacks : public BLEAdvertisedDeviceCallbacks {
  * BLEscan used to retrieve BLE advertized data from devices without connection
  */
 void BLEscan() {
-  TIMERG0.wdt_wprotect = TIMG_WDT_WKEY_VALUE;
-  TIMERG0.wdt_feed = 1;
-  TIMERG0.wdt_wprotect = 0;
+  disableCore0WDT();
   Log.notice(F("Scan begin" CR));
   BLEDevice::init("");
-  BLEScan* pBLEScan = BLEDevice::getScan(); //create new scan
+  BLEScan* pBLEScan = BLEDevice::getScan();
   MyAdvertisedDeviceCallbacks myCallbacks;
   pBLEScan->setAdvertisedDeviceCallbacks(&myCallbacks);
-  pBLEScan->setActiveScan(true); //active scan uses more power, but get results faster
+  pBLEScan->setActiveScan(ActiveBLEScan);
+  pBLEScan->setInterval(BLEScanInterval);
+  pBLEScan->setWindow(BLEScanWindow);
   BLEScanResults foundDevices = pBLEScan->start(Scan_duration / 1000, false);
   scanCount++;
   Log.notice(F("Found %d devices, scan number %d end deinit controller" CR), foundDevices.getCount(), scanCount);
   BLEDevice::deinit(true);
+  enableCore0WDT();
 }
 
 /** 

main/config_BT.h

@@ -48,7 +48,16 @@ bool bleConnect = AttemptBLECOnnect;
 #define MinimumRSSI        -100 //default minimum rssi value, all the devices below -90 will not be reported
 
 #ifndef Scan_duration
-#  define Scan_duration 10000 //define the time for a scan --WARNING-- changing this value can lead to instability on ESP32
+#  define Scan_duration 10000 //define the time for a scan
+#endif
+#ifndef BLEScanInterval
+#  define BLEScanInterval 52 // How often the scan occurs / switches channels; in milliseconds,
+#endif
+#ifndef BLEScanWindow
+#  define BLEScanWindow 30 // How long to scan during the interval; in milliseconds.
+#endif
+#ifndef ActiveBLEScan
+#  define ActiveBLEScan true // Set active scanning, this will get more data from the advertiser.
 #endif
 #ifndef ScanBeforeConnect
 #  define ScanBeforeConnect 10 //define number of scans before connecting to BLE devices (ESP32 only, minimum 1)