Add optional over deviation blanking.

FMBlanking.h

@@ -0,0 +1,41 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#if !defined(FMBlanking_H)
+#define  FMBlanking_H
+
+#include "Config.h"
+
+class CFMBlanking {
+public:
+  CFMBlanking();
+
+  void setParams(uint8_t value, uint8_t level);
+
+  q15_t process(q15_t sample);
+
+private:
+  q15_t    m_posValue;
+  q15_t    m_negValue;
+  q15_t    m_level;
+  bool     m_running;
+  uint32_t m_pos;
+  uint8_t  m_n;
+};
+
+#endif