Slow freq events to 4 per second

include/hamlib/rig.h

@@ -2663,7 +2663,7 @@ typedef unsigned int rig_comm_status_t;
  * that may be updated (ie. customized)
  *
  * It is NOT fine to move fields around as it can break share library offset
- * As of 2021-03-03  vfo_list is the last known item being reference externally
+ * As of 2024-03-03  freq_event_elapsed is the last known item being reference externally
  * So any additions or changes to this structure must be at the end of the structure
  */
 struct rig_state {
@@ -2849,6 +2849,7 @@ struct rig_state {
     char device_id[HAMLIB_RIGNAMSIZ];
     int dual_watch; /*!< Boolean DUAL_WATCH status */
     int post_ptt_delay;         /*!< delay after PTT to allow for relays and such */
+    struct timespec freq_event_elapsed;
 // New rig_state items go before this line ============================================
 };
 

src/event.c

@@ -627,12 +627,22 @@ int rig_fire_freq_event(RIG *rig, vfo_t vfo, freq_t freq)
         rig->state.use_cached_freq = 1;
     }
 
-
-    network_publish_rig_transceive_data(rig);
-
-    if (rig->callbacks.freq_event)
+    if (rig->state.freq_event_elapsed.tv_sec == 0)
     {
-        rig->callbacks.freq_event(rig, vfo, freq, rig->callbacks.freq_arg);
+        elapsed_ms(&rig->state.freq_event_elapsed, HAMLIB_ELAPSED_SET);
+    }
+
+    double e = elapsed_ms(&rig->state.freq_event_elapsed, HAMLIB_ELAPSED_GET);
+
+    if (e >= 250) // throttle events to 4 per sec
+    {
+        elapsed_ms(&rig->state.freq_event_elapsed, HAMLIB_ELAPSED_SET);
+        network_publish_rig_transceive_data(rig);
+
+        if (rig->callbacks.freq_event)
+        {
+            rig->callbacks.freq_event(rig, vfo, freq, rig->callbacks.freq_arg);
+        }
     }
 
     RETURNFUNC(0);