Add special check for IC821H in icom_set_vfo

Seems the IC821H reverses Main/Sub logic when in satmode
Remove IC821 from riglist.h and icom.c -- not used
https://github.com/Hamlib/Hamlib/issues/693

include/hamlib/riglist.h

@@ -215,7 +215,7 @@
 #define RIG_MODEL_IC775 RIG_MAKE_MODEL(RIG_ICOM, 30)
 #define RIG_MODEL_IC781 RIG_MAKE_MODEL(RIG_ICOM, 31)
 #define RIG_MODEL_IC820 RIG_MAKE_MODEL(RIG_ICOM, 32)
-#define RIG_MODEL_IC821 RIG_MAKE_MODEL(RIG_ICOM, 33)
+//#define RIG_MODEL_IC821 RIG_MAKE_MODEL(RIG_ICOM, 33) // not implemented and can be reused
 #define RIG_MODEL_IC821H RIG_MAKE_MODEL(RIG_ICOM, 34)
 #define RIG_MODEL_IC970 RIG_MAKE_MODEL(RIG_ICOM, 35)
 #define RIG_MODEL_ICR10 RIG_MAKE_MODEL(RIG_ICOM, 36)

rigs/icom/ic821h.c

@@ -74,7 +74,8 @@ int ic821h_set_split_vfo(RIG *rig, vfo_t vfo, split_t split, vfo_t tx_vfo)
         rig_debug(RIG_DEBUG_TRACE, "%s: tx_vfo==MAIN so assuming sat mode=%d\n",
                   __func__, rig->state.cache.satmode);
         priv->tx_vfo = split == RIG_SPLIT_ON ? RIG_VFO_SUB : RIG_VFO_MAIN;
-        retval = rig_set_vfo(rig, RIG_VFO_MAIN);
+        // the IC821 seems to be backwards in satmode -- setting Main select Sub and vice versa
+        retval = rig_set_vfo(rig, RIG_VFO_SUB);
     }
     else if (tx_vfo == RIG_VFO_A)
     {

rigs/icom/icom.c

@@ -574,7 +574,6 @@ static const struct icom_addr icom_addr_list[] =
     {RIG_MODEL_IC785x, 0x8e},
     {RIG_MODEL_IC781, 0x26},
     {RIG_MODEL_IC820, 0x42},
-    {RIG_MODEL_IC821, 0x4c},
     {RIG_MODEL_IC821H, 0x4c},
     {RIG_MODEL_IC910, 0x60},
     {RIG_MODEL_IC9100, 0x7c},
@@ -2257,6 +2256,9 @@ int icom_set_vfo(RIG *rig, vfo_t vfo)
         vfo = RIG_VFO_MAIN;
 
         if (rig->state.cache.split == RIG_SPLIT_ON && !rig->state.cache.satmode) { vfo = RIG_VFO_A; }
+
+        // Seems the IC821H reverses Main/Sub when in satmode
+        if (rig->caps->rig_model == RIG_MODEL_IC821H && rig->state.cache.satmode) { vfo = RIG_VFO_SUB; }
     }
     else if ((vfo == RIG_VFO_B || vfo == RIG_VFO_SUB) && VFO_HAS_DUAL)
     {
@@ -2271,6 +2273,9 @@ int icom_set_vfo(RIG *rig, vfo_t vfo)
             vfo = RIG_VFO_SUB_A;
         }
         else if (rig->state.cache.split == RIG_SPLIT_ON) { vfo = RIG_VFO_B; }
+
+        // Seems the IC821H reverses Main/Sub when in satmode
+        if (rig->caps->rig_model == RIG_MODEL_IC821H && rig->state.cache.satmode) { vfo = RIG_VFO_MAIN; }
     }
     else if ((vfo == RIG_VFO_A || vfo == RIG_VFO_B) && !VFO_HAS_A_B
              && VFO_HAS_MAIN_SUB)

rigs/icom/icom.h

@@ -30,7 +30,7 @@
 #include <sys/time.h>
 #endif
 
-#define BACKEND_VER "20210430"
+#define BACKEND_VER "20210507"
 
 /*
  * defines used by comp_cal_str in rig.c