Fix unidirectional rig cached frequency (e.g. FT736R)

https://github.com/Hamlib/Hamlib/issues/1187

include/hamlib/rig.h

@@ -3395,6 +3395,7 @@ extern HAMLIB_EXPORT(int) rig_set_vfo_opt(RIG *rig, int status);
 extern HAMLIB_EXPORT(int) rig_get_vfo_info(RIG *rig, vfo_t vfo, freq_t *freq, rmode_t *mode, pbwidth_t *width, split_t *split, int *satmode);
 extern HAMLIB_EXPORT(int) rig_get_rig_info(RIG *rig, char *response, int max_response_len);
 extern HAMLIB_EXPORT(int) rig_get_cache(RIG *rig, vfo_t vfo, freq_t *freq, int * cache_ms_freq, rmode_t *mode, int *cache_ms_mode, pbwidth_t *width, int *cache_ms_width);
+extern HAMLIB_EXPORT(int) rig_get_cache_freq(RIG *rig, vfo_t vfo, freq_t *freq, int * cache_ms_freq);
 
 extern HAMLIB_EXPORT(int) rig_set_clock(RIG *rig, int year, int month, int day, int hour, int min, int sec, double msec, int utc_offset);
 extern HAMLIB_EXPORT(int) rig_get_clock(RIG *rig, int *year, int *month, int *day, int *hour, int *min, int *sec, double *msec, int *utc_offset);

rigs/yaesu/ft736.c

@@ -31,6 +31,7 @@
 #include "misc.h"
 #include "yaesu.h"
 #include "tones.h"
+#include "cache.h"
 
 
 
@@ -99,7 +100,7 @@ const struct rig_caps ft736_caps =
     RIG_MODEL(RIG_MODEL_FT736R),
     .model_name =         "FT-736R",
     .mfg_name =           "Yaesu",
-    .version =            "20221214.0",
+    .version =            "20221218.0",
     .copyright =          "LGPL",
     .status =             RIG_STATUS_STABLE,
     .rig_type =           RIG_TYPE_TRANSCEIVER,
@@ -270,6 +271,7 @@ int ft736_set_freq(RIG *rig, vfo_t vfo, freq_t freq)
 {
     unsigned char cmd[YAESU_CMD_LENGTH] = { 0x00, 0x00, 0x00, 0x00, 0x01};
     struct ft736_priv_data *priv = (struct ft736_priv_data *)rig->state.priv;
+    int retval;
 
     // we will assume requesting to set VFOB is split mode
     if (vfo == RIG_VFO_B) { return rig_set_split_freq(rig, vfo, freq); }
@@ -288,8 +290,11 @@ int ft736_set_freq(RIG *rig, vfo_t vfo, freq_t freq)
         cmd[0] = (cmd[0] & 0x0f) | 0xc0;
     }
 
-    /* Frequency set */
+    retval = write_block(&rig->state.rigport, cmd, YAESU_CMD_LENGTH);
-    return write_block(&rig->state.rigport, cmd, YAESU_CMD_LENGTH);
+
+    if (retval == RIG_OK) { rig_set_cache_freq(rig, vfo, freq); }
+
+    return retval;
 }
 
 int ft736_get_freq(RIG *rig, vfo_t vfo, freq_t *freq)
@@ -297,7 +302,7 @@ int ft736_get_freq(RIG *rig, vfo_t vfo, freq_t *freq)
     rig_debug(RIG_DEBUG_VERBOSE, "%s: called\n", __func__);
 
     if (vfo == RIG_VFO_A || vfo == RIG_VFO_MAIN) { *freq = rig->state.cache.freqMainA; }
-    else { *freq = rig->state.cache.freqMainB; }
+    else { rig_get_cache_freq(rig, vfo, freq, NULL); }
 
     return RIG_OK;
 }

src/cache.c

@@ -442,6 +442,41 @@ int rig_get_cache(RIG *rig, vfo_t vfo, freq_t *freq, int *cache_ms_freq,
     return RIG_OK;
 }
 
+/**
+ * \brief get cached values for a VFO
+ * \param rig           The rig handle
+ * \param vfo           The VFO to get information from
+ * \param freq          The frequency is stored here
+ * \param cache_ms_freq The age of the last frequency update in ms -- NULL if you don't want it
+
+ * Use this to query the frequency cache and then determine to actually fetch data from
+ * the rig.
+ *
+ * \return RIG_OK if the operation has been successful, otherwise
+ * a negative value if an error occurred (in which case, cause is
+ * set appropriately).
+ *
+ */
+int rig_get_cache_freq(RIG *rig, vfo_t vfo, freq_t *freq, int *cache_ms_freq_p)
+{
+    rmode_t mode;
+    int cache_ms_freq;
+    int cache_ms_mode;
+    pbwidth_t width;
+    int cache_ms_width;
+    int retval;
+    retval = rig_get_cache(rig, vfo, freq, &cache_ms_freq, &mode, &cache_ms_mode,
+                           &width, &cache_ms_width);
+
+    if (retval == RIG_OK)
+    {
+        if (cache_ms_freq_p) { *cache_ms_freq_p = cache_ms_freq; }
+    }
+
+    return retval;
+}
+
+
 void rig_cache_show(RIG *rig, const char *func, int line)
 {
     rig_debug(RIG_DEBUG_CACHE,

src/rig.c

@@ -1806,7 +1806,11 @@ int HAMLIB_API rig_set_freq(RIG *rig, vfo_t vfo, freq_t freq)
 
             if (retcode != RIG_OK) { RETURNFUNC(retcode); }
 
+            // Unidirectional rigs do not reset cache
+            if (rig->caps->rig_model != RIG_MODEL_FT736R)
+            {
                 rig_set_cache_freq(rig, vfo, (freq_t)0);
+            }
 
 #if 0 // this verification seems to be causing bad behavior on some rigs