AP_Mount: Add MNTx_SYSID_DFLT param to easily target another vehicle

libraries/AP_Mount/AP_Mount_Alexmos.cpp

@@ -14,6 +14,7 @@ void AP_Mount_Alexmos::init()
         read_params(0); //we request parameters for profile 0 and therfore get global and profile parameters
         set_mode((enum MAV_MOUNT_MODE)_params.default_mode.get());
     }
+    AP_Mount_Backend::init();
 }
 
 // update mount position - should be called periodically

libraries/AP_Mount/AP_Mount_Backend.cpp

@@ -7,6 +7,13 @@ extern const AP_HAL::HAL& hal;
 
 #define AP_MOUNT_UPDATE_DT 0.02     // update rate in seconds.  update() should be called at this rate
 
+// Default init function for every mount
+void AP_Mount_Backend::init()
+{
+    // setting default target sysid from parameters
+    _target_sysid = _params.sysid_default.get();
+}
+
 // set angle target in degrees
 // yaw_is_earth_frame (aka yaw_lock) should be true if yaw angle is earth-frame, false if body-frame
 void AP_Mount_Backend::set_angle_target(float roll_deg, float pitch_deg, float yaw_deg, bool yaw_is_earth_frame)

libraries/AP_Mount/AP_Mount_Backend.h

@@ -35,7 +35,7 @@ public:
     {}
 
     // init - performs any required initialisation for this instance
-    virtual void init() = 0;
+    virtual void init();
 
     // update mount position - should be called periodically
     virtual void update() = 0;

libraries/AP_Mount/AP_Mount_Gremsy.h

@@ -18,9 +18,6 @@ public:
     // Constructor
     using AP_Mount_Backend::AP_Mount_Backend;
 
-    // init
-    void init() override {}
-
     // update mount position
     void update() override;
 

libraries/AP_Mount/AP_Mount_Params.cpp

@@ -152,6 +152,12 @@ const AP_Param::GroupInfo AP_Mount_Params::var_info[] = {
     // @User: Standard
     AP_GROUPINFO("_LEAD_PTCH", 13, AP_Mount_Params, pitch_stb_lead, 0.0f),
 
+    // @Param: _SYSID_DFLT
+    // @DisplayName: Mount Target sysID
+    // @Description: Default Target sysID for the mount to point to
+    // @RebootRequired: True
+    // @User: Standard
+    AP_GROUPINFO("_SYSID_DFLT", 14, AP_Mount_Params, sysid_default, 0),
     AP_GROUPEND
 };
 

libraries/AP_Mount/AP_Mount_Params.h

@@ -29,4 +29,5 @@ public:
 
     AP_Float    roll_stb_lead;      // roll lead control gain (only used by servo backend)
     AP_Float    pitch_stb_lead;     // pitch lead control gain (only used by servo backend)
+    AP_Int8     sysid_default;      // target sysid for mount to follow
 };

libraries/AP_Mount/AP_Mount_SToRM32.h

@@ -17,9 +17,6 @@ public:
     // Constructor
     using AP_Mount_Backend::AP_Mount_Backend;
 
-    // init - performs any required initialisation for this instance
-    void init() override {}
-
     // update mount position - should be called periodically
     void update() override;
 

libraries/AP_Mount/AP_Mount_SToRM32_serial.cpp

@@ -16,6 +16,7 @@ void AP_Mount_SToRM32_serial::init()
         _initialised = true;
         set_mode((enum MAV_MOUNT_MODE)_params.default_mode.get());
     }
+    AP_Mount_Backend::init();
 
 }
 

libraries/AP_Mount/AP_Mount_Scripting.h

@@ -22,9 +22,6 @@ public:
     /* Do not allow copies */
     CLASS_NO_COPY(AP_Mount_Scripting);
 
-    // init - performs any required initialisation for this instance
-    void init() override {};
-
     // update mount position - should be called periodically
     void update() override;
 

libraries/AP_Mount/AP_Mount_Servo.cpp

@@ -21,6 +21,7 @@ void AP_Mount_Servo::init()
         _pan_idx  = SRV_Channel::k_mount2_pan;
         _open_idx = SRV_Channel::k_mount2_open;
     }
+    AP_Mount_Backend::init();
 }
 
 // update mount position - should be called periodically

libraries/AP_Mount/AP_Mount_Siyi.cpp

@@ -33,7 +33,7 @@ void AP_Mount_Siyi::init()
         _initialised = true;
         set_mode((enum MAV_MOUNT_MODE)_params.default_mode.get());
     }
-
+    AP_Mount_Backend::init();
 }
 
 // update mount position - should be called periodically

libraries/AP_Mount/AP_Mount_SoloGimbal.cpp

@@ -16,6 +16,7 @@ void AP_Mount_SoloGimbal::init()
 {
     _initialised = true;
     set_mode((enum MAV_MOUNT_MODE)_params.default_mode.get());
+    AP_Mount_Backend::init();
 }
 
 void AP_Mount_SoloGimbal::update_fast()