diff --git a/libraries/AP_Compass/AP_Compass_HMC5843.cpp b/libraries/AP_Compass/AP_Compass_HMC5843.cpp
index 12809d74a8..080eaad0ab 100644
--- a/libraries/AP_Compass/AP_Compass_HMC5843.cpp
+++ b/libraries/AP_Compass/AP_Compass_HMC5843.cpp
@@ -138,6 +138,9 @@ AP_Compass_HMC5843::init()
   uint16_t expected_yz = 715;
   float gain_multiple = 1.0;
 
+  // call the parent class init for common code
+  Compass::init();
+
   delay(10);
 
   // determine if we are using 5843 or 5883L
diff --git a/libraries/AP_Compass/Compass.cpp b/libraries/AP_Compass/Compass.cpp
index ea9586b49d..c9d4a4e7be 100644
--- a/libraries/AP_Compass/Compass.cpp
+++ b/libraries/AP_Compass/Compass.cpp
@@ -5,6 +5,8 @@ const AP_Param::GroupInfo Compass::var_info[] PROGMEM = {
     AP_GROUPINFO("ORIENT", 0, Compass, _orientation_matrix),
     AP_GROUPINFO("OFS",    1, Compass, _offset),
     AP_GROUPINFO("DEC",    2, Compass, _declination),
+    AP_GROUPINFO("LEARN",  3, Compass, _learn), // true if learning calibration
+    AP_GROUPINFO("USE",    4, Compass, _use_for_yaw), // true if used for DCM yaw
     AP_GROUPEND
 };
 
@@ -30,6 +32,14 @@ Compass::Compass(void) :
 bool
 Compass::init()
 {
+    // enable learning by default
+    if (!_learn.load()) {
+        _learn.set(1);
+    }
+    // enable use for yaw calculation by default
+    if (!_use_for_yaw.load()) {
+        _use_for_yaw.set(1);
+    }
     return true;
 }
 
@@ -166,15 +176,18 @@ Compass::calculate(const Matrix3f &dcm_matrix)
 void
 Compass::null_offsets(const Matrix3f &dcm_matrix)
 {
+    if (_null_enable == false || _learn == 0) {
+        // auto-calibration is disabled
+        return;
+    }
+
     // Update our estimate of the offsets in the magnetometer
-    Vector3f    calc(0.0, 0.0, 0.0);        // XXX should be safe to remove explicit init here as the default ctor should do the right thing
+    Vector3f    calc;
     Matrix3f    dcm_new_from_last;
     float       weight;
 
     Vector3f mag_body_new = Vector3f(mag_x,mag_y,mag_z);
     
-    if(_null_enable == false) return;
-
     if(_null_init_done) {
         dcm_new_from_last = dcm_matrix.transposed() * _last_dcm_matrix;      // Note 11/20/2010: transpose() is not working, transposed() is.
 
@@ -192,7 +205,6 @@ Compass::null_offsets(const Matrix3f &dcm_matrix)
     }
     _mag_body_last = mag_body_new - calc;
     _last_dcm_matrix = dcm_matrix;
-
 }
 
 
diff --git a/libraries/AP_Compass/Compass.h b/libraries/AP_Compass/Compass.h
index a047ef0717..cc3bc5e704 100644
--- a/libraries/AP_Compass/Compass.h
+++ b/libraries/AP_Compass/Compass.h
@@ -124,6 +124,8 @@ public:
 	///
 	void null_offsets_disable(void);
 
+    /// return true if the compass should be used for yaw calculations
+    bool use_for_yaw(void) { return healthy && _use_for_yaw; }
 
 	/// Sets the local magnetic field declination.
 	///
@@ -138,6 +140,8 @@ protected:
 	AP_Matrix3f         _orientation_matrix;
 	AP_Vector3f         _offset;
 	AP_Float            _declination;
+    AP_Int8             _learn;                 ///<enable calibration learning
+    AP_Int8             _use_for_yaw;           ///<enable use for yaw calculation
 
 	bool                _null_enable;        	///< enabled flag for offset nulling
 	bool                _null_init_done;        ///< first-time-around flag used by offset nulling