Added a circular buffer to store 4 hours worth of watch signal strength for a graph

app/src/main/java/uk/org/openseizuredetector/SdData.java

@@ -69,6 +69,7 @@ public class SdData implements Parcelable {
 
     public CircBuf watchBattBuff = new CircBuf(24*3600/5, -1);  // 24 hour buffer
     public CircBuf phoneBattBuff = new CircBuf(24*3600/5, -1);  // 24 hour buffer
+    public CircBuf watchSignalStrengthBuff = new CircBuf(4*3600/5, -1); // 4 hour buffer
 
     /* Heart Rate Alarm Settings */
     public boolean mHRAlarmActive = false;

app/src/main/java/uk/org/openseizuredetector/SdDataSourceBLE2.java

@@ -497,7 +497,7 @@ public class SdDataSourceBLE2 extends SdDataSource {
         public void onReadRemoteRssi(@NotNull BluetoothPeripheral peripheral, int rssi, @NotNull GattStatus status) {
             Log.d(TAG, String.format("Rssi = %d", rssi));
             mSdData.watchSignalStrength = rssi;
-
+            mSdData.watchSignalStrengthBuff.add(rssi);
         }
 
     };