diff --git a/flight/libraries/auxmagsupport.c b/flight/libraries/auxmagsupport.c
index 3d27e336a..f87c1a50b 100644
--- a/flight/libraries/auxmagsupport.c
+++ b/flight/libraries/auxmagsupport.c
@@ -37,16 +37,26 @@ AuxMagSettingsTypeOptions option;
 
 void auxmagsupport_reload_settings()
 {
+    AuxMagSettingsData cal;
+    float magQuat[4];
+    float R[3][3];
+
+    AuxMagSettingsGet(&cal);
+    mag_bias[0] = cal.mag_bias.X;
+    mag_bias[1] = cal.mag_bias.Y;
+    mag_bias[2] = cal.mag_bias.Z;
+
+    // convert the RPY mag board rotation to into a rotation matrix
+    // rotate the vector into the level hover frame (the attitude frame)
+    const float magRpy[3] = { cal.BoardRotation.Roll, cal.BoardRotation.Pitch, cal.BoardRotation.Yaw };
+    RPY2Quaternion(magRpy, magQuat);
+    Quaternion2R(magQuat, R);
+
+    // the mag transform only scales the raw mag values
+    matrix_mult_3x3f((float(*)[3])AuxMagSettingsmag_transformToArray(cal.mag_transform), R, mag_transform);
+
+    // GPSV9, Ext (unused), and Flexi
     AuxMagSettingsTypeGet(&option);
-    float a[3][3];
-    float b[3][3];
-    float rotz;
-    AuxMagSettingsmag_transformArrayGet((float *)a);
-    AuxMagSettingsOrientationGet(&rotz);
-    rotz = DEG2RAD(rotz);
-    rot_about_axis_z(rotz, b);
-    matrix_mult_3x3f(a, b, mag_transform);
-    AuxMagSettingsmag_biasArrayGet(mag_bias);
 }
 
 void auxmagsupport_publish_samples(float mags[3], uint8_t status)
diff --git a/flight/modules/Sensors/sensors.c b/flight/modules/Sensors/sensors.c
index 800d8a94c..d91a7c7d8 100644
--- a/flight/modules/Sensors/sensors.c
+++ b/flight/modules/Sensors/sensors.c
@@ -57,6 +57,9 @@
 
 #include <attitudesettings.h>
 #include <revocalibration.h>
+#include <auxmagsettings.h>
+#include <auxmagsensor.h>
+#include <auxmagsupport.h>
 #include <accelgyrosettings.h>
 #include <revosettings.h>
 
@@ -81,7 +84,7 @@
 #define REGISTER_WDG()
 #endif
 
-static const TickType_t sensor_period_ticks = ((uint32_t)1000.0f / PIOS_SENSOR_RATE) / portTICK_RATE_MS;
+static const TickType_t sensor_period_ticks = ((uint32_t)(1000.0f / PIOS_SENSOR_RATE / (float)portTICK_RATE_MS));
 
 // Interval in number of sample to recalculate temp bias
 #define TEMP_CALIB_INTERVAL      30
@@ -99,8 +102,8 @@ static const float temp_alpha_gyro_accel = LPF_ALPHA(TEMP_DT_GYRO_ACCEL, TEMP_LP
 #define TEMP_LPF_FC_BARO         5.0f
 static const float temp_alpha_baro = TEMP_DT_BARO / (TEMP_DT_BARO + 1.0f / (2.0f * M_PI_F * TEMP_LPF_FC_BARO));
 
-
 #define ZERO_ROT_ANGLE           0.00001f
+
 // Private types
 typedef struct {
     // used to accumulate all samples in a task iteration
@@ -138,6 +141,7 @@ static void clearContext(sensor_fetch_context *sensor_context);
 static void handleAccel(float *samples, float temperature);
 static void handleGyro(float *samples, float temperature);
 static void handleMag(float *samples, float temperature);
+static void handleAuxMag(float *samples);
 static void handleBaro(float sample, float temperature);
 
 static void updateAccelTempBias(float temperature);
@@ -151,7 +155,6 @@ RevoCalibrationData cal;
 AccelGyroSettingsData agcal;
 
 // These values are initialized by settings but can be updated by the attitude algorithm
-
 static float mag_bias[3] = { 0, 0, 0 };
 static float mag_transform[3][3] = {
     { 1, 0, 0 }, { 0, 1, 0 }, { 0, 0, 1 }
@@ -168,9 +171,11 @@ static float gyro_temp_bias[3] = { 0 };
 static uint8_t accel_temp_calibration_count = 0;
 static uint8_t gyro_temp_calibration_count  = 0;
 
+// The user specified "Rotate virtual attitude relative to board"
 static float R[3][3] = {
     { 0 }
 };
+
 // Variables used to handle baro temperature bias
 static RevoSettingsBaroTempCorrectionPolynomialData baroCorrection;
 static RevoSettingsBaroTempCorrectionExtentData baroCorrectionExtent;
@@ -179,8 +184,6 @@ static float baro_temp_bias   = 0;
 static float baro_temperature = NAN;
 static uint8_t baro_temp_calibration_count = 0;
 
-static int8_t rotate = 0;
-
 /**
  * Initialise the module.  Called before the start function
  * \returns 0 on success or -1 if initialisation failed
@@ -197,7 +200,9 @@ int32_t SensorsInitialize(void)
     AttitudeSettingsInitialize();
     AccelGyroSettingsInitialize();
 
-    rotate = 0;
+    // for auxmagsupport.c helpers
+    AuxMagSettingsInitialize();
+    AuxMagSensorInitialize();
 
     RevoSettingsConnectCallback(&settingsUpdatedCb);
     RevoCalibrationConnectCallback(&settingsUpdatedCb);
@@ -258,6 +263,7 @@ static void SensorsTask(__attribute__((unused)) void *parameters)
     bool sensors_test = true;
     uint8_t count     = 0;
     LL_FOREACH((PIOS_SENSORS_Instance *)sensors_list, sensor) {
+        RELOAD_WDG(); // mag tests on I2C have 200+(7x10)ms delay calls in them
         sensors_test &= PIOS_SENSORS_Test(sensor);
         count++;
     }
@@ -361,20 +367,29 @@ static void processSamples3d(sensor_fetch_context *sensor_context, const PIOS_SE
     PIOS_SENSORS_GetScales(sensor, scales, MAX_SENSORS_PER_INSTANCE);
     float inv_count = 1.0f / (float)sensor_context->count;
     if ((sensor->type & PIOS_SENSORS_TYPE_3AXIS_ACCEL) ||
-        (sensor->type == PIOS_SENSORS_TYPE_3AXIS_MAG)) {
+        (sensor->type == PIOS_SENSORS_TYPE_3AXIS_MAG) ||
+        (sensor->type == PIOS_SENSORS_TYPE_3AXIS_AUXMAG)) {
         float t = inv_count * scales[0];
         samples[0]  = ((float)sensor_context->accum[0].x * t);
         samples[1]  = ((float)sensor_context->accum[0].y * t);
         samples[2]  = ((float)sensor_context->accum[0].z * t);
         temperature = (float)sensor_context->temperature * inv_count * 0.01f;
-        if (sensor->type == PIOS_SENSORS_TYPE_3AXIS_MAG) {
+        switch (sensor->type) {
+        case PIOS_SENSORS_TYPE_3AXIS_MAG:
             handleMag(samples, temperature);
             PERF_MEASURE_PERIOD(counterMagPeriod);
             return;
-        } else {
+
+        case PIOS_SENSORS_TYPE_3AXIS_AUXMAG:
+            handleAuxMag(samples);
+            PERF_MEASURE_PERIOD(counterMagPeriod);
+            return;
+
+        default:
             PERF_TRACK_VALUE(counterAccelSamples, sensor_context->count);
             PERF_MEASURE_PERIOD(counterAccelPeriod);
             handleAccel(samples, temperature);
+            break;
         }
     }
 
@@ -458,6 +473,11 @@ static void handleMag(float *samples, float temperature)
     MagSensorSet(&mag);
 }
 
+static void handleAuxMag(float *samples)
+{
+    auxmagsupport_publish_samples(samples, AUXMAGSENSOR_STATUS_OK);
+}
+
 static void handleBaro(float sample, float temperature)
 {
     updateBaroTempBias(temperature);
@@ -535,58 +555,47 @@ static void updateBaroTempBias(float temperature)
     }
     baro_temp_calibration_count--;
 }
+
 /**
- * Locally cache some variables from the AtttitudeSettings object
+ * Locally cache some variables from the AttitudeSettings object
  */
 static void settingsUpdatedCb(__attribute__((unused)) UAVObjEvent *objEv)
 {
     RevoCalibrationGet(&cal);
-    AccelGyroSettingsGet(&agcal);
     mag_bias[0] = cal.mag_bias.X;
     mag_bias[1] = cal.mag_bias.Y;
     mag_bias[2] = cal.mag_bias.Z;
 
+    AccelGyroSettingsGet(&agcal);
     accel_temp_calibrated = (agcal.temp_calibrated_extent.max - agcal.temp_calibrated_extent.min > .1f) &&
                             (fabsf(agcal.accel_temp_coeff.X) > 1e-9f || fabsf(agcal.accel_temp_coeff.Y) > 1e-9f || fabsf(agcal.accel_temp_coeff.Z) > 1e-9f);
-
     gyro_temp_calibrated  = (agcal.temp_calibrated_extent.max - agcal.temp_calibrated_extent.min > .1f) &&
                             (fabsf(agcal.gyro_temp_coeff.X) > 1e-9f || fabsf(agcal.gyro_temp_coeff.Y) > 1e-9f ||
                             fabsf(agcal.gyro_temp_coeff.Z) > 1e-9f || fabsf(agcal.gyro_temp_coeff.Z2) > 1e-9f);
 
-
+    // convert BoardRotation ("rotate virtual") into a quaternion
     AttitudeSettingsData attitudeSettings;
     AttitudeSettingsGet(&attitudeSettings);
-
-    // Indicates not to expend cycles on rotation
-    if (fabsf(attitudeSettings.BoardRotation.Roll) < ZERO_ROT_ANGLE
-        && fabsf(attitudeSettings.BoardRotation.Pitch) < ZERO_ROT_ANGLE &&
-        fabsf(attitudeSettings.BoardRotation.Yaw) < ZERO_ROT_ANGLE) {
-        rotate = 0;
-    } else {
-        rotate = 1;
-    }
-
     const float rpy[3] = { attitudeSettings.BoardRotation.Roll,
                            attitudeSettings.BoardRotation.Pitch,
                            attitudeSettings.BoardRotation.Yaw };
-
     float rotationQuat[4];
     RPY2Quaternion(rpy, rotationQuat);
 
-    if (fabsf(attitudeSettings.BoardLevelTrim.Roll) > ZERO_ROT_ANGLE ||
-        fabsf(attitudeSettings.BoardLevelTrim.Pitch) > ZERO_ROT_ANGLE) {
-        float trimQuat[4];
-        float sumQuat[4];
-        rotate = 1;
+    // convert BoardLevelTrim ("board level calibration") into a quaternion
+    float trimQuat[4];
+    float sumQuat[4];
+    const float trimRpy[3] = { attitudeSettings.BoardLevelTrim.Roll, attitudeSettings.BoardLevelTrim.Pitch, 0.0f };
+    // do we actually want to include BoardLevelTrim in the mag rotation?  BoardRotation yes, but BoardLevelTrim?
+    // and is BoardLevelTrim done at the correct point in the sequence of rotations?
+    RPY2Quaternion(trimRpy, trimQuat);
 
-        const float trimRpy[3] = { attitudeSettings.BoardLevelTrim.Roll, attitudeSettings.BoardLevelTrim.Pitch, 0.0f };
-        RPY2Quaternion(trimRpy, trimQuat);
+    // add the boardrotation and boardtrim rotations and put them into a rotation matrix
+    quat_mult(rotationQuat, trimQuat, sumQuat);
+    Quaternion2R(sumQuat, R);
 
-        quat_mult(rotationQuat, trimQuat, sumQuat);
-        Quaternion2R(sumQuat, R);
-    } else {
-        Quaternion2R(rotationQuat, R);
-    }
+    // mag_transform is only a scaling
+    // so add the scaling, and store the result in mag_transform for run time use
     matrix_mult_3x3f((float(*)[3])RevoCalibrationmag_transformToArray(cal.mag_transform), R, mag_transform);
 
     RevoSettingsBaroTempCorrectionPolynomialGet(&baroCorrection);
diff --git a/flight/modules/System/systemmod.c b/flight/modules/System/systemmod.c
index 8c94ec1b1..cf8e36225 100644
--- a/flight/modules/System/systemmod.c
+++ b/flight/modules/System/systemmod.c
@@ -183,6 +183,10 @@ static void systemTask(__attribute__((unused)) void *parameters)
         vTaskDelay(10);
     }
 
+#ifndef PIOS_INCLUDE_WDG
+// if no watchdog is enabled, don't reset watchdog in MODULE_TASKCREATE_ALL loop
+#define PIOS_WDG_Clear()
+#endif
     /* create all modules thread */
     MODULE_TASKCREATE_ALL;
 
diff --git a/flight/pios/common/pios_hmc5x83.c b/flight/pios/common/pios_hmc5x83.c
index 0a16c4d64..b471d821f 100644
--- a/flight/pios/common/pios_hmc5x83.c
+++ b/flight/pios/common/pios_hmc5x83.c
@@ -45,6 +45,8 @@ typedef struct {
     uint32_t port_id;
     uint8_t  slave_num;
     uint8_t  CTRLB;
+    uint16_t magCountMax;
+    uint16_t magCount;
     volatile bool data_ready;
 } pios_hmc5x83_dev_data_t;
 
@@ -66,6 +68,7 @@ const PIOS_SENSORS_Driver PIOS_HMC5x83_Driver = {
     .get_scale = PIOS_HMC5x83_driver_get_scale,
     .is_polled = true,
 };
+
 /**
  * Allocate the device setting structure
  * @return pios_hmc5x83_dev_data_t pointer to newly created structure
@@ -104,20 +107,73 @@ pios_hmc5x83_dev_t PIOS_HMC5x83_Init(const struct pios_hmc5x83_cfg *cfg, uint32_
     dev->cfg       = cfg; // store config before enabling interrupt
     dev->port_id   = port_id;
     dev->slave_num = slave_num;
-#ifdef PIOS_HMC5X83_HAS_GPIOS
-    PIOS_EXTI_Init(cfg->exti_cfg);
-#endif
 
-    int32_t val = PIOS_HMC5x83_Config(dev);
-    PIOS_Assert(val == 0);
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    if (cfg->exti_cfg) {
+        PIOS_EXTI_Init(cfg->exti_cfg);
+    } else
+#endif /* PIOS_HMC5X83_HAS_GPIOS */
+    {
+// if PIOS_SENSOR_RATE is defined, there is a sensor loop that is called at that frequency
+// and "is data available" can simply return false a few times to save some CPU
+#ifdef PIOS_SENSOR_RATE
+        // for external mags that have no interrupt line, just poll them with a timer
+        // use the configured Output Data Rate to calculate the number of interations (of the main sensor task loop)
+        // to return false, before returning true
+        uint16_t rate100;
+        switch (cfg->M_ODR) {
+        case PIOS_HMC5x83_ODR_0_75:
+            rate100 = 75;
+            break;
+        case PIOS_HMC5x83_ODR_1_5:
+            rate100 = 150;
+            break;
+        case PIOS_HMC5x83_ODR_3:
+            rate100 = 300;
+            break;
+        case PIOS_HMC5x83_ODR_7_5:
+            rate100 = 750;
+            break;
+        case PIOS_HMC5x83_ODR_15:
+            rate100 = 1500;
+            break;
+        case PIOS_HMC5x83_ODR_30:
+            rate100 = 3000;
+            break;
+        default:
+        case PIOS_HMC5x83_ODR_75:
+            rate100 = 7500;
+            break;
+        }
+        // if the application sensor rate is fast enough to warrant skipping some slow hardware sensor reads
+        if ((PIOS_SENSOR_RATE * 100.0f / 3.0f) > rate100) {
+            // count the number of "return false" up to this number
+            dev->magCountMax = ((uint16_t)PIOS_SENSOR_RATE * 100 / rate100) + 1;
+        } else {
+            // return true every time (do a hardware sensor poll every time)
+            dev->magCountMax = 1;
+        }
+#else /* PIOS_SENSOR_RATE */
+        // return true every time (do a hardware sensor poll every time)
+        dev->magCountMax = 1;
+#endif /* PIOS_SENSOR_RATE */
+        // with this counter
+        dev->magCount    = 0;
+    }
+
+    if (PIOS_HMC5x83_Config(dev) != 0) {
+        return (pios_hmc5x83_dev_t)NULL;
+    }
 
     dev->data_ready = false;
     return (pios_hmc5x83_dev_t)dev;
 }
 
-void PIOS_HMC5x83_Register(pios_hmc5x83_dev_t handler)
+void PIOS_HMC5x83_Register(pios_hmc5x83_dev_t handler, PIOS_SENSORS_TYPE sensortype)
 {
-    PIOS_SENSORS_Register(&PIOS_HMC5x83_Driver, PIOS_SENSORS_TYPE_3AXIS_MAG, handler);
+    if (handler) {
+        PIOS_SENSORS_Register(&PIOS_HMC5x83_Driver, sensortype, handler);
+    }
 }
 
 /**
@@ -212,6 +268,52 @@ static int32_t PIOS_HMC5x83_Config(pios_hmc5x83_dev_data_t *dev)
     return 0;
 }
 
+static void PIOS_HMC5x83_Orient(enum PIOS_HMC5X83_ORIENTATION orientation, int16_t in[3], int16_t out[3])
+{
+    switch (orientation) {
+    case PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP:
+        out[0] = in[2];
+        out[1] = in[0];
+        out[2] = -in[1];
+        break;
+    case PIOS_HMC5X83_ORIENTATION_SOUTH_EAST_UP:
+        out[0] = -in[0];
+        out[1] = in[2];
+        out[2] = -in[1];
+        break;
+    case PIOS_HMC5X83_ORIENTATION_WEST_SOUTH_UP:
+        out[0] = -in[2];
+        out[1] = -in[0];
+        out[2] = -in[1];
+        break;
+    case PIOS_HMC5X83_ORIENTATION_NORTH_WEST_UP:
+        out[0] = in[0];
+        out[1] = -in[2];
+        out[2] = -in[1];
+        break;
+    case PIOS_HMC5X83_ORIENTATION_EAST_SOUTH_DOWN:
+        out[0] = in[2];
+        out[1] = -in[0];
+        out[2] = in[1];
+        break;
+    case PIOS_HMC5X83_ORIENTATION_SOUTH_WEST_DOWN:
+        out[0] = -in[0];
+        out[1] = -in[2];
+        out[2] = in[1];
+        break;
+    case PIOS_HMC5X83_ORIENTATION_WEST_NORTH_DOWN:
+        out[0] = -in[2];
+        out[1] = in[0];
+        out[2] = in[1];
+        break;
+    case PIOS_HMC5X83_ORIENTATION_NORTH_EAST_DOWN:
+        out[0] = in[0];
+        out[1] = in[2];
+        out[2] = in[1];
+        break;
+    }
+}
+
 /**
  * @brief Read current X, Z, Y values (in that order)
  * \param[in] dev device handler
@@ -265,50 +367,14 @@ int32_t PIOS_HMC5x83_ReadMag(pios_hmc5x83_dev_t handler, int16_t out[3])
         temp[i] = v;
     }
 
-    switch (dev->cfg->Orientation) {
-    case PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP:
-        out[0] = temp[2];
-        out[1] = temp[0];
-        out[2] = -temp[1];
-        break;
-    case PIOS_HMC5X83_ORIENTATION_SOUTH_EAST_UP:
-        out[0] = -temp[0];
-        out[1] = temp[2];
-        out[2] = -temp[1];
-        break;
-    case PIOS_HMC5X83_ORIENTATION_WEST_SOUTH_UP:
-        out[0] = -temp[2];
-        out[1] = -temp[0];
-        out[2] = -temp[1];
-        break;
-    case PIOS_HMC5X83_ORIENTATION_NORTH_WEST_UP:
-        out[0] = temp[0];
-        out[1] = -temp[2];
-        out[2] = -temp[1];
-        break;
-    case PIOS_HMC5X83_ORIENTATION_EAST_SOUTH_DOWN:
-        out[0] = temp[2];
-        out[1] = -temp[0];
-        out[2] = temp[1];
-        break;
-    case PIOS_HMC5X83_ORIENTATION_SOUTH_WEST_DOWN:
-        out[0] = -temp[0];
-        out[1] = -temp[2];
-        out[2] = temp[1];
-        break;
-    case PIOS_HMC5X83_ORIENTATION_WEST_NORTH_DOWN:
-        out[0] = -temp[2];
-        out[1] = temp[0];
-        out[2] = temp[1];
-        break;
-    case PIOS_HMC5X83_ORIENTATION_NORTH_EAST_DOWN:
-        out[0] = temp[0];
-        out[1] = temp[2];
-        out[2] = temp[1];
-        break;
-    }
+    PIOS_HMC5x83_Orient(dev->cfg->Orientation, temp, out);
 
-    // This should not be necessary but for some reason it is coming out of continuous conversion mode
+    // "This should not be necessary but for some reason it is coming out of continuous conversion mode"
+    //
+    // By default the chip is in single read mode meaning after reading from it once, it will go idle to save power.
+    // Once idle, we have write to it to turn it on before we can read from it again.
+    // To conserve current between measurements, the device is placed in a state similar to idle mode, but the
+    // Mode Register is not changed to Idle Mode.  That is, MD[n] bits are unchanged.
     dev->cfg->Driver->Write(handler, PIOS_HMC5x83_MODE_REG, PIOS_HMC5x83_MODE_CONTINUOUS);
 
     return 0;
@@ -334,11 +400,23 @@ uint8_t PIOS_HMC5x83_ReadID(pios_hmc5x83_dev_t handler, uint8_t out[4])
  * \return true if new data is available
  * \return false if new data is not available
  */
-bool PIOS_HMC5x83_NewDataAvailable(pios_hmc5x83_dev_t handler)
+bool PIOS_HMC5x83_NewDataAvailable(__attribute__((unused)) pios_hmc5x83_dev_t handler)
 {
     pios_hmc5x83_dev_data_t *dev = dev_validate(handler);
 
-    return dev->data_ready;
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    if (dev->cfg->exti_cfg) { // if this device has an interrupt line attached, then wait for interrupt to say data is ready
+        return dev->data_ready;
+    } else
+#endif /* PIOS_HMC5X83_HAS_GPIOS */
+    { // else poll to see if data is ready or just say "true" and set polling interval elsewhere
+        if (++(dev->magCount) >= dev->magCountMax) {
+            dev->magCount = 0;
+            return true;
+        } else {
+            return false;
+        }
+    }
 }
 
 /**
@@ -435,6 +513,7 @@ int32_t PIOS_HMC5x83_Test(pios_hmc5x83_dev_t handler)
     return failed;
 }
 
+#ifdef PIOS_HMC5X83_HAS_GPIOS
 /**
  * @brief IRQ Handler
  */
@@ -443,8 +522,10 @@ bool PIOS_HMC5x83_IRQHandler(pios_hmc5x83_dev_t handler)
     pios_hmc5x83_dev_data_t *dev = dev_validate(handler);
 
     dev->data_ready = true;
+
     return false;
 }
+#endif /* PIOS_HMC5X83_HAS_GPIOS */
 
 #ifdef PIOS_INCLUDE_SPI
 int32_t PIOS_HMC5x83_SPI_Read(pios_hmc5x83_dev_t handler, uint8_t address, uint8_t *buffer, uint8_t len);
@@ -529,8 +610,8 @@ int32_t PIOS_HMC5x83_SPI_Write(pios_hmc5x83_dev_t handler, uint8_t address, uint
     return 0;
 }
 #endif /* PIOS_INCLUDE_SPI */
-#ifdef PIOS_INCLUDE_I2C
 
+#ifdef PIOS_INCLUDE_I2C
 int32_t PIOS_HMC5x83_I2C_Read(pios_hmc5x83_dev_t handler, uint8_t address, uint8_t *buffer, uint8_t len);
 int32_t PIOS_HMC5x83_I2C_Write(pios_hmc5x83_dev_t handler, uint8_t address, uint8_t buffer);
 
diff --git a/flight/pios/inc/pios_hmc5x83.h b/flight/pios/inc/pios_hmc5x83.h
index 490168017..02206ed66 100644
--- a/flight/pios/inc/pios_hmc5x83.h
+++ b/flight/pios/inc/pios_hmc5x83.h
@@ -95,6 +95,9 @@
 #define PIOS_HMC5x83_Sensitivity_5_6Ga  330     // LSB/Ga
 #define PIOS_HMC5x83_Sensitivity_8_1Ga  230     // LSB/Ga  --> NOT RECOMMENDED
 
+/* Status Register */
+#define PIOS_HMC5x83_DATAOUT_STATUS_RDY 0x01
+
 typedef uintptr_t pios_hmc5x83_dev_t;
 
 struct pios_hmc5x83_io_driver {
@@ -137,7 +140,7 @@ struct pios_hmc5x83_cfg {
 
 /* Public Functions */
 extern pios_hmc5x83_dev_t PIOS_HMC5x83_Init(const struct pios_hmc5x83_cfg *cfg, uint32_t port_id, uint8_t device_num);
-extern void PIOS_HMC5x83_Register(pios_hmc5x83_dev_t handler);
+extern void PIOS_HMC5x83_Register(pios_hmc5x83_dev_t handler, PIOS_SENSORS_TYPE sensortype);
 
 extern bool PIOS_HMC5x83_NewDataAvailable(pios_hmc5x83_dev_t handler);
 extern int32_t PIOS_HMC5x83_ReadMag(pios_hmc5x83_dev_t handler, int16_t out[3]);
diff --git a/flight/pios/inc/pios_initcall.h b/flight/pios/inc/pios_initcall.h
index 55b3e15f9..6142a9703 100644
--- a/flight/pios/inc/pios_initcall.h
+++ b/flight/pios/inc/pios_initcall.h
@@ -100,10 +100,12 @@ extern void StartModules();
       initTaskDone = 1; \
     }
 
-#define MODULE_TASKCREATE_ALL \
+#define MODULE_TASKCREATE_ALL    \
     { for (initmodule_t *fn = __module_initcall_start; fn < __module_initcall_end; fn++) { \
-          if (fn->fn_tinit) { \
-              (fn->fn_tinit)(); } \
+          if (fn->fn_tinit) {    \
+              (fn->fn_tinit)();  \
+              PIOS_WDG_Clear();  \
+          } \
       } \
     }
 
diff --git a/flight/pios/inc/pios_sensors.h b/flight/pios/inc/pios_sensors.h
index eb565c14a..085fe96f2 100644
--- a/flight/pios/inc/pios_sensors.h
+++ b/flight/pios/inc/pios_sensors.h
@@ -54,15 +54,16 @@ typedef struct PIOS_SENSORS_Driver {
 } PIOS_SENSORS_Driver;
 
 typedef enum PIOS_SENSORS_TYPE {
-    PIOS_SENSORS_TYPE_3AXIS_ACCEL = 0x01,
-    PIOS_SENSORS_TYPE_3AXIS_GYRO  = 0x02,
+    PIOS_SENSORS_TYPE_3AXIS_ACCEL      = 0x01,
+    PIOS_SENSORS_TYPE_3AXIS_GYRO       = 0x02,
     PIOS_SENSORS_TYPE_3AXIS_GYRO_ACCEL = 0x03,
-    PIOS_SENSORS_TYPE_3AXIS_MAG   = 0x04,
-    PIOS_SENSORS_TYPE_1AXIS_BARO  = 0x08,
+    PIOS_SENSORS_TYPE_3AXIS_MAG        = 0x04,
+    PIOS_SENSORS_TYPE_3AXIS_AUXMAG     = 0x08,
+    PIOS_SENSORS_TYPE_1AXIS_BARO       = 0x10,
 } PIOS_SENSORS_TYPE;
 
 #define PIOS_SENSORS_TYPE_1D (PIOS_SENSORS_TYPE_1AXIS_BARO)
-#define PIOS_SENSORS_TYPE_3D (PIOS_SENSORS_TYPE_3AXIS_ACCEL | PIOS_SENSORS_TYPE_3AXIS_GYRO | PIOS_SENSORS_TYPE_3AXIS_MAG)
+#define PIOS_SENSORS_TYPE_3D (PIOS_SENSORS_TYPE_3AXIS_ACCEL | PIOS_SENSORS_TYPE_3AXIS_GYRO | PIOS_SENSORS_TYPE_3AXIS_MAG | PIOS_SENSORS_TYPE_3AXIS_AUXMAG)
 
 typedef struct PIOS_SENSORS_Instance {
     const PIOS_SENSORS_Driver    *driver;
diff --git a/flight/pios/stm32f10x/pios_i2c.c b/flight/pios/stm32f10x/pios_i2c.c
index d68f5d071..77f150ac0 100644
--- a/flight/pios/stm32f10x/pios_i2c.c
+++ b/flight/pios/stm32f10x/pios_i2c.c
@@ -711,6 +711,12 @@ static bool i2c_adapter_wait_for_stopped(struct pios_i2c_adapter *i2c_adapter)
 
 static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter)
 {
+    // retry with wait code from
+    // TauLabs 20150718 - Prevent F3 I2C Init Lockup #1728
+    uint8_t retry_count;
+    uint8_t retry_count_clk;
+    static const uint8_t MAX_I2C_RETRY_COUNT = 10;
+
     /* Reset the I2C block */
     I2C_DeInit(i2c_adapter->cfg->regs);
 
@@ -731,11 +737,13 @@ static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter)
     /* have to be repeated (due to futher bus errors) but better than clocking 0xFF into an */
     /* ESC */
     // bool sda_hung = GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET;
-    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET) {
+    retry_count_clk = 0;
+    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET && (retry_count_clk++ < MAX_I2C_RETRY_COUNT)) {
+        retry_count = 0;
         /* Set clock high and wait for any clock stretching to finish. */
         GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
-        while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET) {
-            ;
+        while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET && (retry_count++ < MAX_I2C_RETRY_COUNT)) {
+            PIOS_DELAY_WaituS(1);
         }
         PIOS_DELAY_WaituS(2);
 
@@ -759,12 +767,14 @@ static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter)
     /* Set data and clock high and wait for any clock stretching to finish. */
     GPIO_SetBits(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin);
     GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
-    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET) {
-        ;
+    retry_count = 0;
+    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET && (retry_count++ < MAX_I2C_RETRY_COUNT)) {
+        PIOS_DELAY_WaituS(1);
     }
     /* Wait for data to be high */
-    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) != Bit_SET) {
-        ;
+    retry_count = 0;
+    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) != Bit_SET && (retry_count++ < MAX_I2C_RETRY_COUNT)) {
+        PIOS_DELAY_WaituS(1);
     }
 
 
diff --git a/flight/pios/stm32f4xx/pios_i2c.c b/flight/pios/stm32f4xx/pios_i2c.c
index 171669ac4..60811fa13 100644
--- a/flight/pios/stm32f4xx/pios_i2c.c
+++ b/flight/pios/stm32f4xx/pios_i2c.c
@@ -390,6 +390,7 @@ static const struct i2c_adapter_transition i2c_adapter_transitions[I2C_STATE_NUM
     },
 };
 
+
 static void go_fsm_fault(struct pios_i2c_adapter *i2c_adapter)
 {
 #if defined(I2C_HALT_ON_ERRORS)
@@ -401,6 +402,7 @@ static void go_fsm_fault(struct pios_i2c_adapter *i2c_adapter)
     i2c_adapter_reset_bus(i2c_adapter);
 }
 
+
 static void go_bus_error(struct pios_i2c_adapter *i2c_adapter)
 {
     /* Note that this transfer has hit a bus error */
@@ -409,6 +411,7 @@ static void go_bus_error(struct pios_i2c_adapter *i2c_adapter)
     i2c_adapter_reset_bus(i2c_adapter);
 }
 
+
 static void go_stopping(struct pios_i2c_adapter *i2c_adapter)
 {
 #ifdef USE_FREERTOS
@@ -431,12 +434,14 @@ static void go_stopping(struct pios_i2c_adapter *i2c_adapter)
     }
 }
 
+
 static void go_stopped(struct pios_i2c_adapter *i2c_adapter)
 {
     I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, DISABLE);
     I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, ENABLE);
 }
 
+
 static void go_starting(struct pios_i2c_adapter *i2c_adapter)
 {
     PIOS_DEBUG_Assert(i2c_adapter->active_txn);
@@ -465,6 +470,7 @@ static void go_starting(struct pios_i2c_adapter *i2c_adapter)
     }
 }
 
+
 /* Common to 'more' and 'last' transaction */
 static void go_r_any_txn_addr(struct pios_i2c_adapter *i2c_adapter)
 {
@@ -477,24 +483,28 @@ static void go_r_any_txn_addr(struct pios_i2c_adapter *i2c_adapter)
     I2C_Send7bitAddress(i2c_adapter->cfg->regs, (i2c_adapter->active_txn->addr) << 1, I2C_Direction_Receiver);
 }
 
+
 static void go_r_more_txn_pre_one(struct pios_i2c_adapter *i2c_adapter)
 {
     I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, DISABLE);
     I2C_GenerateSTART(i2c_adapter->cfg->regs, ENABLE);
 }
 
+
 static void go_r_last_txn_pre_one(struct pios_i2c_adapter *i2c_adapter)
 {
     I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, DISABLE);
     I2C_GenerateSTOP(i2c_adapter->cfg->regs, ENABLE);
 }
 
+
 /* Common to 'more' and 'last' transaction */
 static void go_r_any_txn_pre_first(struct pios_i2c_adapter *i2c_adapter)
 {
     I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, ENABLE);
 }
 
+
 /* Common to 'more' and 'last' transaction */
 static void go_r_any_txn_pre_middle(struct pios_i2c_adapter *i2c_adapter)
 {
@@ -508,6 +518,7 @@ static void go_r_any_txn_pre_middle(struct pios_i2c_adapter *i2c_adapter)
     PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
 }
 
+
 static void go_r_more_txn_pre_last(struct pios_i2c_adapter *i2c_adapter)
 {
     PIOS_DEBUG_Assert(i2c_adapter->active_byte);
@@ -526,6 +537,7 @@ static void go_r_more_txn_pre_last(struct pios_i2c_adapter *i2c_adapter)
     PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
 }
 
+
 static void go_r_last_txn_pre_last(struct pios_i2c_adapter *i2c_adapter)
 {
     PIOS_DEBUG_Assert(i2c_adapter->active_byte);
@@ -544,6 +556,7 @@ static void go_r_last_txn_pre_last(struct pios_i2c_adapter *i2c_adapter)
     PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
 }
 
+
 /* Common to 'more' and 'last' transaction */
 static void go_r_any_txn_post_last(struct pios_i2c_adapter *i2c_adapter)
 {
@@ -562,6 +575,7 @@ static void go_r_any_txn_post_last(struct pios_i2c_adapter *i2c_adapter)
     i2c_adapter->active_txn++;
 }
 
+
 /* Common to 'more' and 'last' transaction */
 static void go_w_any_txn_addr(struct pios_i2c_adapter *i2c_adapter)
 {
@@ -574,6 +588,7 @@ static void go_w_any_txn_addr(struct pios_i2c_adapter *i2c_adapter)
     I2C_Send7bitAddress(i2c_adapter->cfg->regs, (i2c_adapter->active_txn->addr) << 1, I2C_Direction_Transmitter);
 }
 
+
 static void go_w_any_txn_middle(struct pios_i2c_adapter *i2c_adapter)
 {
     PIOS_DEBUG_Assert(i2c_adapter->active_byte);
@@ -589,6 +604,7 @@ static void go_w_any_txn_middle(struct pios_i2c_adapter *i2c_adapter)
     PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
 }
 
+
 static void go_w_more_txn_last(struct pios_i2c_adapter *i2c_adapter)
 {
     PIOS_DEBUG_Assert(i2c_adapter->active_byte);
@@ -607,6 +623,7 @@ static void go_w_more_txn_last(struct pios_i2c_adapter *i2c_adapter)
     PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
 }
 
+
 static void go_w_last_txn_last(struct pios_i2c_adapter *i2c_adapter)
 {
     PIOS_DEBUG_Assert(i2c_adapter->active_byte);
@@ -625,6 +642,7 @@ static void go_w_last_txn_last(struct pios_i2c_adapter *i2c_adapter)
     i2c_adapter->active_byte++;
 }
 
+
 static void go_nack(struct pios_i2c_adapter *i2c_adapter)
 {
     i2c_adapter->nack = true;
@@ -633,6 +651,7 @@ static void go_nack(struct pios_i2c_adapter *i2c_adapter)
     I2C_GenerateSTOP(i2c_adapter->cfg->regs, ENABLE);
 }
 
+
 static void i2c_adapter_inject_event(struct pios_i2c_adapter *i2c_adapter, enum i2c_adapter_event event)
 {
     PIOS_IRQ_Disable();
@@ -668,6 +687,7 @@ static void i2c_adapter_inject_event(struct pios_i2c_adapter *i2c_adapter, enum
     PIOS_IRQ_Enable();
 }
 
+
 static void i2c_adapter_process_auto(struct pios_i2c_adapter *i2c_adapter)
 {
     PIOS_IRQ_Disable();
@@ -684,12 +704,14 @@ static void i2c_adapter_process_auto(struct pios_i2c_adapter *i2c_adapter)
     PIOS_IRQ_Enable();
 }
 
+
 static void i2c_adapter_fsm_init(struct pios_i2c_adapter *i2c_adapter)
 {
     i2c_adapter_reset_bus(i2c_adapter);
     i2c_adapter->curr_state = I2C_STATE_STOPPED;
 }
 
+
 static bool i2c_adapter_wait_for_stopped(struct pios_i2c_adapter *i2c_adapter)
 {
     uint32_t guard;
@@ -712,8 +734,15 @@ static bool i2c_adapter_wait_for_stopped(struct pios_i2c_adapter *i2c_adapter)
     return true;
 }
 
+
 static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter)
 {
+    // retry with wait code from
+    // TauLabs 20150718 - Prevent F3 I2C Init Lockup #1728
+    uint8_t retry_count;
+    uint8_t retry_count_clk;
+    static const uint8_t MAX_I2C_RETRY_COUNT = 10;
+
     /* Reset the I2C block */
     I2C_DeInit(i2c_adapter->cfg->regs);
 
@@ -734,11 +763,13 @@ static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter)
     /* have to be repeated (due to futher bus errors) but better than clocking 0xFF into an */
     /* ESC */
     // bool sda_hung = GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET;
-    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET) {
+    retry_count_clk = 0;
+    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET && (retry_count_clk++ < MAX_I2C_RETRY_COUNT)) {
+        retry_count = 0;
         /* Set clock high and wait for any clock stretching to finish. */
         GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
-        while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET) {
-            ;
+        while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET && (retry_count++ < MAX_I2C_RETRY_COUNT)) {
+            PIOS_DELAY_WaituS(1);
         }
         PIOS_DELAY_WaituS(2);
 
@@ -762,12 +793,14 @@ static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter)
     /* Set data and clock high and wait for any clock stretching to finish. */
     GPIO_SetBits(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin);
     GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
-    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET) {
-        ;
+    retry_count = 0;
+    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET && (retry_count++ < MAX_I2C_RETRY_COUNT)) {
+        PIOS_DELAY_WaituS(1);
     }
     /* Wait for data to be high */
-    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) != Bit_SET) {
-        ;
+    retry_count = 0;
+    while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) != Bit_SET && (retry_count++ < MAX_I2C_RETRY_COUNT)) {
+        PIOS_DELAY_WaituS(1);
     }
 
 
@@ -818,6 +851,7 @@ static bool i2c_adapter_fsm_terminated(struct pios_i2c_adapter *i2c_adapter)
     }
 }
 
+
 uint32_t i2c_cb_count = 0;
 static bool i2c_adapter_callback_handler(struct pios_i2c_adapter *i2c_adapter)
 {
@@ -872,6 +906,7 @@ static bool i2c_adapter_callback_handler(struct pios_i2c_adapter *i2c_adapter)
     return (!i2c_adapter->bus_error) && semaphore_success;
 }
 
+
 /**
  * Logs the last N state transitions and N IRQ events due to
  * an error condition
@@ -936,6 +971,7 @@ static bool PIOS_I2C_validate(struct pios_i2c_adapter *i2c_adapter)
     return i2c_adapter->magic == PIOS_I2C_DEV_MAGIC;
 }
 
+
 #if defined(PIOS_INCLUDE_FREERTOS) && 0
 static struct pios_i2c_dev *PIOS_I2C_alloc(void)
 {
diff --git a/flight/targets/boards/discoveryf4bare/firmware/inc/pios_config.h b/flight/targets/boards/discoveryf4bare/firmware/inc/pios_config.h
index 2bc9c11b9..a551f858f 100644
--- a/flight/targets/boards/discoveryf4bare/firmware/inc/pios_config.h
+++ b/flight/targets/boards/discoveryf4bare/firmware/inc/pios_config.h
@@ -84,7 +84,7 @@
 // #define PIOS_INCLUDE_MPU6000
 // #define PIOS_MPU6000_ACCEL
 /* #define PIOS_INCLUDE_HMC5843 */
-// #define PIOS_INCLUDE_HMC5X83
+#define PIOS_INCLUDE_HMC5X83
 // #define PIOS_HMC5X83_HAS_GPIOS
 /* #define PIOS_INCLUDE_BMP085 */
 // #define PIOS_INCLUDE_MS5611
diff --git a/flight/targets/boards/discoveryf4bare/firmware/pios_board.c b/flight/targets/boards/discoveryf4bare/firmware/pios_board.c
index bb9f6c33d..80d6af1f7 100644
--- a/flight/targets/boards/discoveryf4bare/firmware/pios_board.c
+++ b/flight/targets/boards/discoveryf4bare/firmware/pios_board.c
@@ -36,6 +36,7 @@
 #include <pios_oplinkrcvr_priv.h>
 #include <taskinfo.h>
 #include <pios_callbackscheduler.h>
+#include <auxmagsettings.h>
 
 #ifdef PIOS_INCLUDE_INSTRUMENTATION
 #include <pios_instrumentation.h>
@@ -92,8 +93,16 @@ void PIOS_ADC_DMC_irq_handler(void)
 
 #if defined(PIOS_INCLUDE_HMC5X83)
 #include "pios_hmc5x83.h"
+pios_hmc5x83_dev_t onboard_mag  = 0;
+pios_hmc5x83_dev_t external_mag = 0;
+
+bool pios_board_internal_mag_handler()
+{
+    return PIOS_HMC5x83_IRQHandler(onboard_mag);
+}
+
 static const struct pios_exti_cfg pios_exti_hmc5x83_cfg __exti_config = {
-    .vector = PIOS_HMC5x83_IRQHandler,
+    .vector = pios_board_internal_mag_handler,
     .line   = EXTI_Line7,
     .pin    = {
         .gpio = GPIOB,
@@ -123,14 +132,30 @@ static const struct pios_exti_cfg pios_exti_hmc5x83_cfg __exti_config = {
     },
 };
 
-static const struct pios_hmc5x83_cfg pios_hmc5x83_cfg = {
-    .exti_cfg    = &pios_exti_hmc5x83_cfg,
-    .M_ODR       = PIOS_HMC5x83_ODR_75,
-    .Meas_Conf   = PIOS_HMC5x83_MEASCONF_NORMAL,
-    .Gain        = PIOS_HMC5x83_GAIN_1_9,
-    .Mode        = PIOS_HMC5x83_MODE_CONTINUOUS,
-    .Driver      = &PIOS_HMC5x83_I2C_DRIVER,
-    .Orientation = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP,
+static const struct pios_hmc5x83_cfg pios_hmc5x83_internal_cfg = {
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    .exti_cfg  = &pios_exti_hmc5x83_cfg,
+#endif
+    .M_ODR     = PIOS_HMC5x83_ODR_75,
+    .Meas_Conf = PIOS_HMC5x83_MEASCONF_NORMAL,
+    .Gain   = PIOS_HMC5x83_GAIN_1_9,
+    .Mode   = PIOS_HMC5x83_MODE_CONTINUOUS,
+    .TempCompensation = false,
+    .Driver = &PIOS_HMC5x83_I2C_DRIVER,
+    .Orientation      = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP,
+};
+
+static const struct pios_hmc5x83_cfg pios_hmc5x83_external_cfg = {
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    .exti_cfg  = NULL,
+#endif
+    .M_ODR     = PIOS_HMC5x83_ODR_75, // if you change this for auxmag, change AUX_MAG_SKIP in sensors.c
+    .Meas_Conf = PIOS_HMC5x83_MEASCONF_NORMAL,
+    .Gain   = PIOS_HMC5x83_GAIN_1_9,
+    .Mode   = PIOS_HMC5x83_MODE_CONTINUOUS,
+    .TempCompensation = false,
+    .Driver = &PIOS_HMC5x83_I2C_DRIVER,
+    .Orientation      = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP, // ENU for GPSV9, WND for typical I2C mag
 };
 #endif /* PIOS_INCLUDE_HMC5X83 */
 
@@ -654,11 +679,40 @@ void PIOS_Board_Init(void)
         break;
     case HWSETTINGS_RM_FLEXIPORT_I2C:
 #if defined(PIOS_INCLUDE_I2C)
-        {
-            if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
-                PIOS_Assert(0);
-            }
+        if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
+            PIOS_Assert(0);
         }
+        PIOS_DELAY_WaitmS(50); // this was after the other PIOS_I2C_Init(), so I copied it here too
+#ifdef PIOS_INCLUDE_WDG
+        // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+        // this is not in a loop, so it is safe
+        // leave this here even if PIOS_INCLUDE_HMC5X83 is undefined
+        // to avoid making something else fail when HMC5X83 is removed
+        PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+#if defined(PIOS_INCLUDE_HMC5X83)
+        // get auxmag type
+        AuxMagSettingsTypeOptions option;
+        AuxMagSettingsInitialize();
+        AuxMagSettingsTypeGet(&option);
+        // if the aux mag type is FlexiPort then set it up
+        if (option == AUXMAGSETTINGS_TYPE_FLEXI) {
+            // attach the 5x83 mag to the previously inited I2C2
+            external_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_external_cfg, pios_i2c_flexiport_adapter_id, 0);
+#ifdef PIOS_INCLUDE_WDG
+            // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+            // this is not in a loop, so it is safe
+            PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+            // add this sensor to the sensor task's list
+            // be careful that you don't register a slow, unimportant sensor after registering the fastest sensor
+            // and before registering some other fast and important sensor
+            // as that would cause delay and time jitter for the second fast sensor
+            PIOS_HMC5x83_Register(external_mag, PIOS_SENSORS_TYPE_3AXIS_AUXMAG);
+            // mag alarm is cleared later, so use I2C
+            AlarmsSet(SYSTEMALARMS_ALARM_I2C, (external_mag) ? SYSTEMALARMS_ALARM_OK : SYSTEMALARMS_ALARM_WARNING);
+        }
+#endif /* PIOS_INCLUDE_HMC5X83 */
 #endif /* PIOS_INCLUDE_I2C */
         break;
     case HWSETTINGS_RM_FLEXIPORT_GPS:
@@ -882,6 +936,7 @@ void PIOS_Board_Init(void)
     };
     GPIO_Init(GPIOA, &gpioA8);
 
+    // init I2C1 for use with the internal mag and baro
     if (PIOS_I2C_Init(&pios_i2c_mag_pressure_adapter_id, &pios_i2c_mag_pressure_adapter_cfg)) {
         PIOS_DEBUG_Assert(0);
     }
@@ -892,8 +947,24 @@ void PIOS_Board_Init(void)
     PIOS_ADC_Init(&pios_adc_cfg);
 #endif
 
+#ifdef PIOS_INCLUDE_WDG
+    // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+    // this is not in a loop, so it is safe
+    // leave this here even if PIOS_INCLUDE_HMC5X83 is undefined
+    // to avoid making something else fail when HMC5X83 is removed
+    PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+
 #if defined(PIOS_INCLUDE_HMC5X83)
-    PIOS_HMC5x83_Init(&pios_hmc5x83_cfg, pios_i2c_mag_pressure_adapter_id, 0);
+    // attach the 5x83 mag to the previously inited I2C1
+    onboard_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_internal_cfg, pios_i2c_mag_pressure_adapter_id, 0);
+#ifdef PIOS_INCLUDE_WDG
+    // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+    // this is not in a loop, so it is safe
+    PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+    // add this sensor to the sensor task's list
+    PIOS_HMC5x83_Register(onboard_mag, PIOS_SENSORS_TYPE_3AXIS_MAG);
 #endif
 
 #if defined(PIOS_INCLUDE_MS5611)
diff --git a/flight/targets/boards/osd/firmware/inc/pios_config.h b/flight/targets/boards/osd/firmware/inc/pios_config.h
index 98f7c22c0..a835f6a99 100644
--- a/flight/targets/boards/osd/firmware/inc/pios_config.h
+++ b/flight/targets/boards/osd/firmware/inc/pios_config.h
@@ -81,7 +81,7 @@
 /* #define PIOS_INCLUDE_MPU6000 */
 /* #define PIOS_MPU6000_ACCEL */
 /* #define PIOS_INCLUDE_HMC5843 */
-#define PIOS_INCLUDE_HMC5X83
+/* #define PIOS_INCLUDE_HMC5X83 */
 /* #define PIOS_HMC5X83_HAS_GPIOS */
 #define PIOS_INCLUDE_BMP085
 /* #define PIOS_INCLUDE_MS5611 */
diff --git a/flight/targets/boards/revolution/firmware/pios_board.c b/flight/targets/boards/revolution/firmware/pios_board.c
index 5bfc0a16c..115a74fab 100644
--- a/flight/targets/boards/revolution/firmware/pios_board.c
+++ b/flight/targets/boards/revolution/firmware/pios_board.c
@@ -36,7 +36,7 @@
 #include <pios_oplinkrcvr_priv.h>
 #include <taskinfo.h>
 #include <pios_ws2811.h>
-
+#include <auxmagsettings.h>
 
 #ifdef PIOS_INCLUDE_INSTRUMENTATION
 #include <pios_instrumentation.h>
@@ -55,12 +55,11 @@
 /**
  * Sensor configurations
  */
-
 #if defined(PIOS_INCLUDE_ADC)
-
 #include "pios_adc_priv.h"
 void PIOS_ADC_DMC_irq_handler(void);
 void DMA2_Stream4_IRQHandler(void) __attribute__((alias("PIOS_ADC_DMC_irq_handler")));
+
 struct pios_adc_cfg pios_adc_cfg = {
     .adc_dev = ADC1,
     .dma     = {
@@ -84,22 +83,25 @@ struct pios_adc_cfg pios_adc_cfg = {
     .half_flag = DMA_IT_HTIF4,
     .full_flag = DMA_IT_TCIF4,
 };
+
 void PIOS_ADC_DMC_irq_handler(void)
 {
     /* Call into the generic code to handle the IRQ for this specific device */
     PIOS_ADC_DMA_Handler();
 }
-
 #endif /* if defined(PIOS_INCLUDE_ADC) */
 
 #if defined(PIOS_INCLUDE_HMC5X83)
 #include "pios_hmc5x83.h"
-pios_hmc5x83_dev_t onboard_mag = 0;
+pios_hmc5x83_dev_t onboard_mag  = 0;
+pios_hmc5x83_dev_t external_mag = 0;
 
+#ifdef PIOS_HMC5X83_HAS_GPIOS
 bool pios_board_internal_mag_handler()
 {
     return PIOS_HMC5x83_IRQHandler(onboard_mag);
 }
+
 static const struct pios_exti_cfg pios_exti_hmc5x83_cfg __exti_config = {
     .vector = pios_board_internal_mag_handler,
     .line   = EXTI_Line7,
@@ -130,15 +132,32 @@ static const struct pios_exti_cfg pios_exti_hmc5x83_cfg __exti_config = {
         },
     },
 };
+#endif /* PIOS_HMC5X83_HAS_GPIOS */
 
-static const struct pios_hmc5x83_cfg pios_hmc5x83_cfg = {
-    .exti_cfg    = &pios_exti_hmc5x83_cfg,
-    .M_ODR       = PIOS_HMC5x83_ODR_75,
-    .Meas_Conf   = PIOS_HMC5x83_MEASCONF_NORMAL,
-    .Gain        = PIOS_HMC5x83_GAIN_1_9,
-    .Mode        = PIOS_HMC5x83_MODE_CONTINUOUS,
-    .Driver      = &PIOS_HMC5x83_I2C_DRIVER,
-    .Orientation = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP,
+static const struct pios_hmc5x83_cfg pios_hmc5x83_internal_cfg = {
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    .exti_cfg  = &pios_exti_hmc5x83_cfg,
+#endif
+    .M_ODR     = PIOS_HMC5x83_ODR_75,
+    .Meas_Conf = PIOS_HMC5x83_MEASCONF_NORMAL,
+    .Gain   = PIOS_HMC5x83_GAIN_1_9,
+    .Mode   = PIOS_HMC5x83_MODE_CONTINUOUS,
+    .TempCompensation = false,
+    .Driver = &PIOS_HMC5x83_I2C_DRIVER,
+    .Orientation      = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP,
+};
+
+static const struct pios_hmc5x83_cfg pios_hmc5x83_external_cfg = {
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    .exti_cfg  = NULL,
+#endif
+    .M_ODR     = PIOS_HMC5x83_ODR_75, // if you change this for auxmag, change AUX_MAG_SKIP in sensors.c
+    .Meas_Conf = PIOS_HMC5x83_MEASCONF_NORMAL,
+    .Gain   = PIOS_HMC5x83_GAIN_1_9,
+    .Mode   = PIOS_HMC5x83_MODE_CONTINUOUS,
+    .TempCompensation = false,
+    .Driver = &PIOS_HMC5x83_I2C_DRIVER,
+    .Orientation      = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP, // ENU for GPSV9, WND for typical I2C mag
 };
 #endif /* PIOS_INCLUDE_HMC5X83 */
 
@@ -247,7 +266,6 @@ uint32_t pios_com_rf_id        = 0;
 uint32_t pios_com_bridge_id    = 0;
 uint32_t pios_com_overo_id     = 0;
 uint32_t pios_com_hkosd_id     = 0;
-
 uint32_t pios_com_vcp_id       = 0;
 
 #if defined(PIOS_INCLUDE_RFM22B)
@@ -368,7 +386,6 @@ void PIOS_Board_Init(void)
     PIOS_LED_Init(led_cfg);
 #endif /* PIOS_INCLUDE_LED */
 
-
 #ifdef PIOS_INCLUDE_INSTRUMENTATION
     PIOS_Instrumentation_Init(PIOS_INSTRUMENTATION_MAX_COUNTERS);
 #endif
@@ -400,6 +417,7 @@ void PIOS_Board_Init(void)
 #if defined(PIOS_INCLUDE_RTC)
     PIOS_RTC_Init(&pios_rtc_main_cfg);
 #endif
+
     /* IAP System Setup */
     PIOS_IAP_Init();
     // check for safe mode commands from gcs
@@ -411,6 +429,7 @@ void PIOS_Board_Init(void)
         PIOS_IAP_WriteBootCmd(1, 0);
         PIOS_IAP_WriteBootCmd(2, 0);
     }
+
 #ifdef PIOS_INCLUDE_WDG
     PIOS_WDG_Init();
 #endif
@@ -471,11 +490,40 @@ void PIOS_Board_Init(void)
         break;
     case HWSETTINGS_RM_FLEXIPORT_I2C:
 #if defined(PIOS_INCLUDE_I2C)
-        {
-            if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
-                PIOS_Assert(0);
-            }
+        if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
+            PIOS_Assert(0);
         }
+        PIOS_DELAY_WaitmS(50); // this was after the other PIOS_I2C_Init(), so I copied it here too
+#ifdef PIOS_INCLUDE_WDG
+        // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+        // this is not in a loop, so it is safe
+        // leave this here even if PIOS_INCLUDE_HMC5X83 is undefined
+        // to avoid making something else fail when HMC5X83 is removed
+        PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+#if defined(PIOS_INCLUDE_HMC5X83)
+        // get auxmag type
+        AuxMagSettingsTypeOptions option;
+        AuxMagSettingsInitialize();
+        AuxMagSettingsTypeGet(&option);
+        // if the aux mag type is FlexiPort then set it up
+        if (option == AUXMAGSETTINGS_TYPE_FLEXI) {
+            // attach the 5x83 mag to the previously inited I2C2
+            external_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_external_cfg, pios_i2c_flexiport_adapter_id, 0);
+#ifdef PIOS_INCLUDE_WDG
+            // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+            // this is not in a loop, so it is safe
+            PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+            // add this sensor to the sensor task's list
+            // be careful that you don't register a slow, unimportant sensor after registering the fastest sensor
+            // and before registering some other fast and important sensor
+            // as that would cause delay and time jitter for the second fast sensor
+            PIOS_HMC5x83_Register(external_mag, PIOS_SENSORS_TYPE_3AXIS_AUXMAG);
+            // mag alarm is cleared later, so use I2C
+            AlarmsSet(SYSTEMALARMS_ALARM_I2C, (external_mag) ? SYSTEMALARMS_ALARM_OK : SYSTEMALARMS_ALARM_WARNING);
+        }
+#endif /* PIOS_INCLUDE_HMC5X83 */
 #endif /* PIOS_INCLUDE_I2C */
         break;
     case HWSETTINGS_RM_FLEXIPORT_GPS:
@@ -662,7 +710,6 @@ void PIOS_Board_Init(void)
     }
 #endif /* PIOS_INCLUDE_USB */
 
-
     /* Configure main USART port */
     uint8_t hwsettings_mainport;
     HwSettingsRM_MainPortGet(&hwsettings_mainport);
@@ -724,7 +771,6 @@ void PIOS_Board_Init(void)
         GPIO_WriteBit(pios_sbus_cfg.inv.gpio, pios_sbus_cfg.inv.init.GPIO_Pin, pios_sbus_cfg.gpio_inv_disable);
     }
 
-
     /* Initalize the RFM22B radio COM device. */
 #if defined(PIOS_INCLUDE_RFM22B)
 
@@ -838,7 +884,6 @@ void PIOS_Board_Init(void)
 #endif /* PIOS_INCLUDE_RFM22B */
 
 #if defined(PIOS_INCLUDE_PWM) || defined(PIOS_INCLUDE_PWM)
-
     const struct pios_servo_cfg *pios_servo_cfg;
     // default to servo outputs only
     pios_servo_cfg = &pios_servo_cfg_out;
@@ -933,10 +978,10 @@ void PIOS_Board_Init(void)
     };
     GPIO_Init(GPIOA, &gpioA8);
 
+    // init I2C1 for use with the internal mag and baro
     if (PIOS_I2C_Init(&pios_i2c_mag_pressure_adapter_id, &pios_i2c_mag_pressure_adapter_cfg)) {
         PIOS_DEBUG_Assert(0);
     }
-
     PIOS_DELAY_WaitmS(50);
 
 #if defined(PIOS_INCLUDE_ADC)
@@ -949,9 +994,24 @@ void PIOS_Board_Init(void)
     PIOS_MPU6000_Register();
 #endif
 
+#ifdef PIOS_INCLUDE_WDG
+    // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+    // this is not in a loop, so it is safe
+    // leave this here even if PIOS_INCLUDE_HMC5X83 is undefined
+    // to avoid making something else fail when HMC5X83 is removed
+    PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+
 #if defined(PIOS_INCLUDE_HMC5X83)
-    onboard_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_cfg, pios_i2c_mag_pressure_adapter_id, 0);
-    PIOS_HMC5x83_Register(onboard_mag);
+    // attach the 5x83 mag to the previously inited I2C1
+    onboard_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_internal_cfg, pios_i2c_mag_pressure_adapter_id, 0);
+#ifdef PIOS_INCLUDE_WDG
+    // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+    // this is not in a loop, so it is safe
+    PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+    // add this sensor to the sensor task's list
+    PIOS_HMC5x83_Register(onboard_mag, PIOS_SENSORS_TYPE_3AXIS_MAG);
 #endif
 
 #if defined(PIOS_INCLUDE_MS5611)
diff --git a/flight/targets/boards/revonano/firmware/inc/pios_config.h b/flight/targets/boards/revonano/firmware/inc/pios_config.h
index 16803c751..e14b9aaf9 100644
--- a/flight/targets/boards/revonano/firmware/inc/pios_config.h
+++ b/flight/targets/boards/revonano/firmware/inc/pios_config.h
@@ -84,7 +84,7 @@
 // #define PIOS_INCLUDE_MPU6000
 // #define PIOS_MPU6000_ACCEL
 /* #define PIOS_INCLUDE_HMC5843 */
-// #define PIOS_INCLUDE_HMC5X83
+#define PIOS_INCLUDE_HMC5X83
 // #define PIOS_HMC5X83_HAS_GPIOS
 /* #define PIOS_INCLUDE_BMP085 */
 #define PIOS_INCLUDE_MS5611
diff --git a/flight/targets/boards/revonano/firmware/pios_board.c b/flight/targets/boards/revonano/firmware/pios_board.c
index dcf373a51..466697182 100644
--- a/flight/targets/boards/revonano/firmware/pios_board.c
+++ b/flight/targets/boards/revonano/firmware/pios_board.c
@@ -38,6 +38,7 @@
 #include <pios_ws2811.h>
 #include <sanitycheck.h>
 #include <actuatorsettings.h>
+#include <auxmagsettings.h>
 
 #ifdef PIOS_INCLUDE_INSTRUMENTATION
 #include <pios_instrumentation.h>
@@ -92,9 +93,26 @@ void PIOS_ADC_DMC_irq_handler(void)
     /* Call into the generic code to handle the IRQ for this specific device */
     PIOS_ADC_DMA_Handler();
 }
-
 #endif /* if defined(PIOS_INCLUDE_ADC) */
 
+#if defined(PIOS_INCLUDE_HMC5X83)
+#include "pios_hmc5x83.h"
+pios_hmc5x83_dev_t external_mag = 0;
+
+static const struct pios_hmc5x83_cfg pios_hmc5x83_external_cfg = {
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    .exti_cfg  = NULL,
+#endif
+    .M_ODR     = PIOS_HMC5x83_ODR_75, // if you change this for auxmag, change AUX_MAG_SKIP in sensors.c
+    .Meas_Conf = PIOS_HMC5x83_MEASCONF_NORMAL,
+    .Gain   = PIOS_HMC5x83_GAIN_1_9,
+    .Mode   = PIOS_HMC5x83_MODE_CONTINUOUS,
+    .TempCompensation = false,
+    .Driver = &PIOS_HMC5x83_I2C_DRIVER,
+    .Orientation      = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP, // ENU for GPSV9, WND for typical I2C mag
+};
+#endif /* PIOS_INCLUDE_HMC5X83 */
+
 /**
  * Configuration for the MS5611 chip
  */
@@ -360,6 +378,7 @@ void PIOS_Board_Init(void)
         PIOS_IAP_WriteBootCmd(1, 0);
         PIOS_IAP_WriteBootCmd(2, 0);
     }
+
 #ifdef PIOS_INCLUDE_WDG
     PIOS_WDG_Init();
 #endif
@@ -617,11 +636,40 @@ void PIOS_Board_Init(void)
         break;
     case HWSETTINGS_RM_FLEXIPORT_I2C:
 #if defined(PIOS_INCLUDE_I2C)
-        {
-            if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
-                PIOS_Assert(0);
-            }
+        if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
+            PIOS_Assert(0);
         }
+        PIOS_DELAY_WaitmS(50); // this was after the other PIOS_I2C_Init(), so I copied it here too
+#ifdef PIOS_INCLUDE_WDG
+        // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+        // this is not in a loop, so it is safe
+        // leave this here even if PIOS_INCLUDE_HMC5X83 is undefined
+        // to avoid making something else fail when HMC5X83 is removed
+        PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+#if defined(PIOS_INCLUDE_HMC5X83)
+        // get auxmag type
+        AuxMagSettingsTypeOptions option;
+        AuxMagSettingsInitialize();
+        AuxMagSettingsTypeGet(&option);
+        // if the aux mag type is FlexiPort then set it up
+        if (option == AUXMAGSETTINGS_TYPE_FLEXI) {
+            // attach the 5x83 mag to the previously inited I2C2
+            external_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_external_cfg, pios_i2c_flexiport_adapter_id, 0);
+#ifdef PIOS_INCLUDE_WDG
+            // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+            // this is not in a loop, so it is safe
+            PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+            // add this sensor to the sensor task's list
+            // be careful that you don't register a slow, unimportant sensor after registering the fastest sensor
+            // and before registering some other fast and important sensor
+            // as that would cause delay and time jitter for the second fast sensor
+            PIOS_HMC5x83_Register(external_mag, PIOS_SENSORS_TYPE_3AXIS_AUXMAG);
+            // mag alarm is cleared later, so use I2C
+            AlarmsSet(SYSTEMALARMS_ALARM_I2C, (external_mag) ? SYSTEMALARMS_ALARM_OK : SYSTEMALARMS_ALARM_WARNING);
+        }
+#endif /* PIOS_INCLUDE_HMC5X83 */
 #endif /* PIOS_INCLUDE_I2C */
         break;
     case HWSETTINGS_RM_FLEXIPORT_GPS:
diff --git a/flight/targets/boards/revoproto/firmware/pios_board.c b/flight/targets/boards/revoproto/firmware/pios_board.c
index b0c9030ec..b88abc4a7 100644
--- a/flight/targets/boards/revoproto/firmware/pios_board.c
+++ b/flight/targets/boards/revoproto/firmware/pios_board.c
@@ -31,6 +31,7 @@
 #include <hwsettings.h>
 #include <manualcontrolsettings.h>
 #include <taskinfo.h>
+#include <auxmagsettings.h>
 
 /*
  * Pull in the board-specific static HW definitions.
@@ -84,8 +85,10 @@ void PIOS_ADC_DMC_irq_handler(void)
 #if defined(PIOS_INCLUDE_HMC5X83)
 #include "pios_hmc5x83.h"
 
-pios_hmc5x83_dev_t onboard_mag = 0;
+pios_hmc5x83_dev_t onboard_mag  = 0;
+pios_hmc5x83_dev_t external_mag = 0;
 
+#ifdef PIOS_HMC5X83_HAS_GPIOS
 bool pios_board_internal_mag_handler()
 {
     return PIOS_HMC5x83_IRQHandler(onboard_mag);
@@ -120,15 +123,32 @@ static const struct pios_exti_cfg pios_exti_hmc5x83_cfg __exti_config = {
         },
     },
 };
+#endif /* PIOS_HMC5X83_HAS_GPIOS */
 
-static const struct pios_hmc5x83_cfg pios_hmc5x83_cfg = {
-    .exti_cfg    = &pios_exti_hmc5x83_cfg,
-    .M_ODR       = PIOS_HMC5x83_ODR_75,
-    .Meas_Conf   = PIOS_HMC5x83_MEASCONF_NORMAL,
-    .Gain        = PIOS_HMC5x83_GAIN_1_9,
-    .Mode        = PIOS_HMC5x83_MODE_CONTINUOUS,
-    .Driver      = &PIOS_HMC5x83_I2C_DRIVER,
-    .Orientation = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP,
+static const struct pios_hmc5x83_cfg pios_hmc5x83_internal_cfg = {
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    .exti_cfg  = &pios_exti_hmc5x83_cfg,
+#endif
+    .M_ODR     = PIOS_HMC5x83_ODR_75,
+    .Meas_Conf = PIOS_HMC5x83_MEASCONF_NORMAL,
+    .Gain   = PIOS_HMC5x83_GAIN_1_9,
+    .Mode   = PIOS_HMC5x83_MODE_CONTINUOUS,
+    .TempCompensation = false,
+    .Driver = &PIOS_HMC5x83_I2C_DRIVER,
+    .Orientation      = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP,
+};
+
+static const struct pios_hmc5x83_cfg pios_hmc5x83_external_cfg = {
+#ifdef PIOS_HMC5X83_HAS_GPIOS
+    .exti_cfg  = NULL,
+#endif
+    .M_ODR     = PIOS_HMC5x83_ODR_75, // if you change this for auxmag, change AUX_MAG_SKIP in sensors.c
+    .Meas_Conf = PIOS_HMC5x83_MEASCONF_NORMAL,
+    .Gain   = PIOS_HMC5x83_GAIN_1_9,
+    .Mode   = PIOS_HMC5x83_MODE_CONTINUOUS,
+    .TempCompensation = false,
+    .Driver = &PIOS_HMC5x83_I2C_DRIVER,
+    .Orientation      = PIOS_HMC5X83_ORIENTATION_EAST_NORTH_UP,
 };
 #endif /* PIOS_INCLUDE_HMC5X83 */
 
@@ -753,14 +773,39 @@ void PIOS_Board_Init(void)
         break;
     case HWSETTINGS_RV_FLEXIPORT_I2C:
 #if defined(PIOS_INCLUDE_I2C)
-        {
-            if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
-                PIOS_Assert(0);
-            }
+        if (PIOS_I2C_Init(&pios_i2c_flexiport_adapter_id, &pios_i2c_flexiport_adapter_cfg)) {
+            PIOS_Assert(0);
         }
+        PIOS_DELAY_WaitmS(50); // this was after the other PIOS_I2C_Init(), so I copied it here too
+#ifdef PIOS_INCLUDE_WDG
+        // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+        // this is not in a loop, so it is safe
+        // leave this here even if PIOS_INCLUDE_HMC5X83 is undefined
+        // to avoid making something else fail when HMC5X83 is removed
+        PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+#if defined(PIOS_INCLUDE_HMC5X83)
+        // get auxmag type
+        AuxMagSettingsTypeOptions option;
+        AuxMagSettingsInitialize();
+        AuxMagSettingsTypeGet(&option);
+        // if the aux mag type is FlexiPort then set it up
+        if (option == AUXMAGSETTINGS_TYPE_FLEXI) {
+            // attach the 5x83 mag to the previously inited I2C2
+            external_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_external_cfg, pios_i2c_flexiport_adapter_id, 0);
+#ifdef PIOS_INCLUDE_WDG
+            // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+            // this is not in a loop, so it is safe
+            PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+            // add this sensor to the sensor task's list
+            PIOS_HMC5x83_Register(external_mag, PIOS_SENSORS_TYPE_3AXIS_AUXMAG);
+            // mag alarm is cleared later, so use I2C
+            AlarmsSet(SYSTEMALARMS_ALARM_I2C, (external_mag) ? SYSTEMALARMS_ALARM_OK : SYSTEMALARMS_ALARM_WARNING);
+        }
+#endif /* PIOS_INCLUDE_HMC5X83 */
 #endif /* PIOS_INCLUDE_I2C */
         break;
-
     case HWSETTINGS_RV_FLEXIPORT_DSM:
         // TODO: Define the various Channelgroup for Revo dsm inputs and handle here
         PIOS_Board_configure_dsm(&pios_usart_dsm_flexi_cfg, &pios_dsm_flexi_cfg,
@@ -879,10 +924,12 @@ void PIOS_Board_Init(void)
     PIOS_DEBUG_Init(pios_tim_servoport_all_pins, NELEMENTS(pios_tim_servoport_all_pins));
 #endif
 
+    // init I2C1 for use with the internal mag
     if (PIOS_I2C_Init(&pios_i2c_mag_adapter_id, &pios_i2c_mag_adapter_cfg)) {
         PIOS_DEBUG_Assert(0);
     }
 
+    // init I2C1 for use with the internal baro
     if (PIOS_I2C_Init(&pios_i2c_pressure_adapter_id, &pios_i2c_pressure_adapter_cfg)) {
         PIOS_DEBUG_Assert(0);
     }
@@ -893,9 +940,24 @@ void PIOS_Board_Init(void)
     PIOS_ADC_Init(&pios_adc_cfg);
 #endif
 
+#ifdef PIOS_INCLUDE_WDG
+    // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+    // this is not in a loop, so it is safe
+    // leave this here even if PIOS_INCLUDE_HMC5X83 is undefined
+    // to avoid making something else fail when HMC5X83 is removed
+    PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+
 #if defined(PIOS_INCLUDE_HMC5X83)
-    onboard_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_cfg, pios_i2c_mag_adapter_id, 0);
-    PIOS_HMC5x83_Register(onboard_mag);
+    // attach the 5x83 mag to the previously inited I2C1
+    onboard_mag = PIOS_HMC5x83_Init(&pios_hmc5x83_internal_cfg, pios_i2c_mag_adapter_id, 0);
+#ifdef PIOS_INCLUDE_WDG
+    // give HMC5x83 on I2C some extra time to allow for reset, etc. if needed
+    // this is not in a loop, so it is safe
+    PIOS_WDG_Clear();
+#endif /* PIOS_INCLUDE_WDG */
+    // add this sensor to the sensor task's list
+    PIOS_HMC5x83_Register(onboard_mag, PIOS_SENSORS_TYPE_3AXIS_MAG);
 #endif
 
 #if defined(PIOS_INCLUDE_MS5611)
diff --git a/ground/gcs/src/plugins/config/configrevowidget.cpp b/ground/gcs/src/plugins/config/configrevowidget.cpp
index 87c1bc29a..79e60a08c 100644
--- a/ground/gcs/src/plugins/config/configrevowidget.cpp
+++ b/ground/gcs/src/plugins/config/configrevowidget.cpp
@@ -246,10 +246,14 @@ void ConfigRevoWidget::storeAndClearBoardRotation()
         AuxMagSettings *auxMagSettings = AuxMagSettings::GetInstance(getObjectManager());
         Q_ASSERT(auxMagSettings);
         AuxMagSettings::DataFields auxMagData = auxMagSettings->getData();
-        auxMagStoredBoardRotation = auxMagData.Orientation;
+        auxMagStoredBoardRotation[AuxMagSettings::BOARDROTATION_YAW]   = auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_YAW];
+        auxMagStoredBoardRotation[AuxMagSettings::BOARDROTATION_ROLL]  = auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_ROLL];
+        auxMagStoredBoardRotation[AuxMagSettings::BOARDROTATION_PITCH] = auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_PITCH];
 
         // Set aux mag board rotation to no rotation
-        auxMagData.Orientation = 0.0f;
+        auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_YAW]    = 0;
+        auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_ROLL]   = 0;
+        auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_PITCH]  = 0;
         auxMagSettings->setData(auxMagData);
     }
 }
@@ -273,7 +277,9 @@ void ConfigRevoWidget::recallBoardRotation()
         AuxMagSettings *auxMagSettings = AuxMagSettings::GetInstance(getObjectManager());
         Q_ASSERT(auxMagSettings);
         AuxMagSettings::DataFields auxMagData = auxMagSettings->getData();
-        auxMagData.Orientation = auxMagStoredBoardRotation;
+        auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_YAW]   = auxMagStoredBoardRotation[AuxMagSettings::BOARDROTATION_YAW];
+        auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_ROLL]  = auxMagStoredBoardRotation[AuxMagSettings::BOARDROTATION_ROLL];
+        auxMagData.BoardRotation[AuxMagSettings::BOARDROTATION_PITCH] = auxMagStoredBoardRotation[AuxMagSettings::BOARDROTATION_PITCH];
         auxMagSettings->setData(auxMagData);
     }
 }
diff --git a/ground/gcs/src/plugins/config/configrevowidget.h b/ground/gcs/src/plugins/config/configrevowidget.h
index 175832b4b..fb9a4aafa 100644
--- a/ground/gcs/src/plugins/config/configrevowidget.h
+++ b/ground/gcs/src/plugins/config/configrevowidget.h
@@ -64,7 +64,7 @@ private:
 
     // Board rotation store/recall for FC and for aux mag
     qint16 storedBoardRotation[3];
-    float auxMagStoredBoardRotation;
+    qint16 auxMagStoredBoardRotation[3];
     bool isBoardRotationStored;
 
 private slots:
diff --git a/shared/uavobjectdefinition/auxmagsettings.xml b/shared/uavobjectdefinition/auxmagsettings.xml
index fda802031..f4a4a882d 100644
--- a/shared/uavobjectdefinition/auxmagsettings.xml
+++ b/shared/uavobjectdefinition/auxmagsettings.xml
@@ -5,8 +5,8 @@
         <field name="mag_transform" units="gain" type="float" elementnames="r0c0,r0c1,r0c2,r1c0,r1c1,r1c2,r2c0,r2c1,r2c2"
          defaultvalue="1,0,0,0,1,0,0,0,1"/>
         <field name="MagBiasNullingRate" units="" type="float" elements="1" defaultvalue="0"/>
-        <field name="Orientation" units="degrees" type="float" elements="1" defaultvalue="0"/>
-        <field name="Type" units="" type="enum" elements="1" options="GPSV9,Ext" defaultvalue="GPSV9"/>
+        <field name="BoardRotation" units="deg" type="int16" elementnames="Roll,Pitch,Yaw" defaultvalue="0,0,0"/>
+        <field name="Type" units="" type="enum" elements="1" options="GPSV9,Ext,Flexi" defaultvalue="GPSV9"/>
         <field name="Usage" units="" type="enum" elements="1" options="Both,OnboardOnly,AuxOnly" defaultvalue="Both"/>
         <access gcs="readwrite" flight="readwrite"/>
         <telemetrygcs acked="true" updatemode="onchange" period="0"/>