* dynamic noise floor sampling

src/Dispatcher.h

@@ -61,6 +61,10 @@ public:
    */
   virtual void loop() { }
 
+  virtual int getNoiseFloor() const { return 0; }
+
+  virtual void triggerNoiseFloorCalibrate() { }
+
   virtual bool isInRecvMode() const = 0;
 
   /**
@@ -112,6 +116,7 @@ class Dispatcher {
   unsigned long next_tx_time;
   unsigned long cad_busy_start;
   unsigned long radio_nonrx_start;
+  unsigned long next_floor_calib_time;
   bool  prev_isrecv_mode;
   uint32_t n_sent_flood, n_sent_direct;
   uint32_t n_recv_flood, n_recv_direct;
@@ -129,6 +134,7 @@ protected:
   {
     outbound = NULL; total_air_time = 0; next_tx_time = 0;
     cad_busy_start = 0;
+    next_floor_calib_time = 0;
     _err_flags = 0;
     radio_nonrx_start = 0;
     prev_isrecv_mode = true;