Index: firmware/App/Modes/ModeUpdate.c
===================================================================
diff -u
--- firmware/App/Modes/ModeUpdate.c	(revision 0)
+++ firmware/App/Modes/ModeUpdate.c	(revision eb159befbbeae67205fb6b55d75743aa4d48c9b0)
@@ -0,0 +1,128 @@
+
+
+#include "Messaging.h"
+#include "ModeUpdate.h"
+#include "OperationModes.h"
+#include "Timers.h"
+
+/**
+ *  @addtogroup DDStandbyMode
+ *  @{
+ */
+
+// ********** private definitions **********
+
+#define BEFORE_MCU_RESET_TIMEOUT_MS                   100                                    ///< Before micro-controller unit reset timeout in milliseconds.
+
+// ********** private data **********
+
+static U32 modeUpdateStartTimeMS;                                                            ///< Mode update start time in milliseconds.
+static DD_UPDATE_STATE_T currentUpdateState;                                                 ///< Current state (sub-mode) of update mode.
+
+// ********** private function prototypes **********
+
+static DD_UPDATE_STATE_T handleUpdateModeStartState( void );
+static DD_UPDATE_STATE_T handleUpdateModeResetMCUState( void );
+
+/*********************************************************************//**
+ * @brief
+ * The initUpdateMode function initializes the Update Mode Unit.
+ * @details \b Inputs: none
+ * @details \b Outputs: currentUpdateState, modeUpdateStartTimeMS
+ * @return none
+ *************************************************************************/
+void initUpdateMode( void )
+{
+    currentUpdateState    = DD_UPDATE_INIT_STATE;
+    modeUpdateStartTimeMS = 0;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The transitionToUpdateMode function prepares for transition to update mode.
+ * @details \b Inputs: none
+ * @details \b Outputs: Update Mode unit re-initialized.
+ * @return initial state
+ *************************************************************************/
+U32 transitionToUpdateMode( void )
+{
+    initUpdateMode();
+
+    // Set the timer when the transition to update mode has been called upon requesting to transition to mode update
+    modeUpdateStartTimeMS = getMSTimerCount();
+
+    return currentUpdateState;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The execUpdateMode function executes the update Mode state machine.
+ * @details \b Inputs: currentUpdateState
+ * @details \b Outputs: currentUpdateState
+ * @return current state (sub-mode)
+ *************************************************************************/
+U32 execUpdateMode( void )
+{
+    switch ( currentUpdateState )
+    {
+        case DD_UPDATE_INIT_STATE:
+            currentUpdateState = handleUpdateModeStartState();
+            break;
+
+        case DD_UPDATE_RESET_MCU_STATE:
+            currentUpdateState = handleUpdateModeResetMCUState();
+            break;
+
+        default:
+            SET_ALARM_WITH_2_U32_DATA( ALARM_ID_TD_SOFTWARE_FAULT, SW_FAULT_ID_MODE_UPDATE_INVALID_STATE, currentUpdateState );
+            currentUpdateState = DD_UPDATE_INIT_STATE;
+            break;
+    }
+
+    return currentUpdateState;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The handleUpdateModeStartState function executes the update mode start
+ * state. The start state transitions to the next state after the specified
+ * timeout.
+ * @details \b Inputs: modeUpdateStartTimeMS
+ * @details \b Outputs: none
+ * @return next state of the update mode state machine
+ *************************************************************************/
+static DD_UPDATE_STATE_T handleUpdateModeStartState( void )
+{
+    DD_UPDATE_STATE_T state = DD_UPDATE_INIT_STATE;
+
+    if ( TRUE == didTimeout( modeUpdateStartTimeMS, BEFORE_MCU_RESET_TIMEOUT_MS ) )
+    {
+        state = DD_UPDATE_RESET_MCU_STATE;
+    }
+
+    return state;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The handleUpdateModeResetMCUState function executes the update mode reset
+ * micro-controller unit state. The state resets the MCU.
+ * @details \b Inputs: none
+ * @details \b Outputs: none
+ * @return next state of the update mode state machine
+ *************************************************************************/
+static DD_UPDATE_STATE_T handleUpdateModeResetMCUState( void )
+{
+    DD_UPDATE_STATE_T state = DD_UPDATE_RESET_MCU_STATE;
+
+    resetMicroControllerUnit();
+
+    return state;
+}
+
+/*************************************************************************
+ *                       TEST SUPPORT FUNCTIONS
+ *************************************************************************/
+
+
+/**@}*/
Index: firmware/App/Modes/ModeUpdate.h
===================================================================
diff -u
--- firmware/App/Modes/ModeUpdate.h	(revision 0)
+++ firmware/App/Modes/ModeUpdate.h	(revision eb159befbbeae67205fb6b55d75743aa4d48c9b0)
@@ -0,0 +1,25 @@
+#ifndef __MODE_UPDATE_H__
+#define __MODE_UPDATE_H__
+
+#include "DDCommon.h"
+#include "DDDefs.h"
+
+/**
+ *  @defgroup DDUpdateMode DDUpdateMode
+ *  @brief Update mode unit. Manages the update mode functions via a state machine.
+ *
+ *  @addtogroup DDUpdateMode
+ *  @{
+ */
+
+// ********** public definitions **********
+
+// ********** public function prototypes **********
+
+void initUpdateMode ( void );
+U32 transitionToUpdateMode( void );
+U32 execUpdateMode( void );
+
+/**@}*/
+
+#endif
Index: firmware/App/Modes/OperationModes.c
===================================================================
diff -u -r6d4aa77e6b85aa7621a234660f631e725fb1d441 -reb159befbbeae67205fb6b55d75743aa4d48c9b0
--- firmware/App/Modes/OperationModes.c	(.../OperationModes.c)	(revision 6d4aa77e6b85aa7621a234660f631e725fb1d441)
+++ firmware/App/Modes/OperationModes.c	(.../OperationModes.c)	(revision eb159befbbeae67205fb6b55d75743aa4d48c9b0)
@@ -22,6 +22,7 @@
 #include "ModePostGenDialysate.h"
 #include "ModeService.h"
 #include "ModeStandby.h"
+#include "ModeUpdate.h"
 #include "MessageSupport.h"
 #include "Messaging.h"
 #include "OperationModes.h"
@@ -56,17 +57,18 @@
 /// This matrix determines legal transitions from one mode to another.
 static const DD_OP_MODE_T MODE_TRANSITION_TABLE[ NUM_OF_DD_MODES - 1 ][ NUM_OF_DD_MODES - 1 ] =
 {
- // from     to->           FAULT        SERVICE         INIT         STANBY        PREG          GEND          POSG              HEAT          HCOL         ROPS
-         /* FAUL     */{ DD_MODE_FAUL, DD_MODE_SERV, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG },
-         /* SERV     */{ DD_MODE_NLEG, DD_MODE_SERV, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG },
-         /* INIT     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_INIT, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG },
-         /* STAN     */{ DD_MODE_FAUL, DD_MODE_SERV, DD_MODE_INIT, DD_MODE_STAN, DD_MODE_PREG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_HEAT, DD_MODE_HCOL, DD_MODE_ROPS },
-         /* PREG     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_PREG, DD_MODE_GEND, DD_MODE_POSG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG },
-         /* GEND     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_GEND, DD_MODE_POSG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG },
-         /* POSG     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_POSG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG },
-         /* HEAT     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_HEAT, DD_MODE_HCOL, DD_MODE_NLEG },
-         /* HCOL     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_HCOL, DD_MODE_NLEG },
-         /* ROPS     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_ROPS },
+ // from     to->           FAULT        SERVICE         INIT         STANBY        PREG          GEND          POSG              HEAT          HCOL         ROPS     UPDATE
+         /* FAUL     */{ DD_MODE_FAUL, DD_MODE_SERV, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_UPDT},
+         /* SERV     */{ DD_MODE_NLEG, DD_MODE_SERV, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_UPDT},
+         /* INIT     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_INIT, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_UPDT},
+         /* STAN     */{ DD_MODE_FAUL, DD_MODE_SERV, DD_MODE_INIT, DD_MODE_STAN, DD_MODE_PREG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_HEAT, DD_MODE_HCOL, DD_MODE_ROPS, DD_MODE_UPDT},
+         /* PREG     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_PREG, DD_MODE_GEND, DD_MODE_POSG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG},
+         /* GEND     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_GEND, DD_MODE_POSG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG},
+         /* POSG     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_POSG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG},
+         /* HEAT     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_HEAT, DD_MODE_HCOL, DD_MODE_NLEG, DD_MODE_NLEG},
+         /* HCOL     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_HCOL, DD_MODE_NLEG, DD_MODE_NLEG},
+         /* ROPS     */{ DD_MODE_FAUL, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_ROPS, DD_MODE_NLEG},
+         /* UPDT     */{ DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_STAN, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_NLEG, DD_MODE_UPDT},
 };
 
 // ********** private function prototypes **********
@@ -112,6 +114,7 @@
     initServiceMode();
     initInitAndPOSTMode();
     initStandbyMode();
+    initUpdateMode();
     initGenDialysateMode();
     initPreGenDialysateMode();
     initPostGenDialysateMode();
@@ -224,6 +227,10 @@
 //            currentSubMode = execROPermeateSampleMode();
 //            break;
 
+        case DD_MODE_UPDT:
+            currentSubMode = execUpdateMode();
+            break;
+
         default:
             SET_ALARM_WITH_2_U32_DATA( ALARM_ID_DD_SOFTWARE_FAULT, SW_FAULT_ID_OP_MODES_INVALID_MODE_STATE, (U32)currentMode )
             currentMode = DD_MODE_FAUL;
@@ -406,6 +413,10 @@
 //            currentSubMode = transitionToROPermeateSampleMode();
 //            break;
 
+        case DD_MODE_UPDT:
+            currentSubMode = transitionToUpdateMode();
+            break;
+
         default:
             SET_ALARM_WITH_2_U32_DATA( ALARM_ID_DD_SOFTWARE_FAULT, SW_FAULT_ID_OP_MODES_INVALID_MODE_TO_TRANSITION_TO, (U32)newMode )
             break;
Index: firmware/App/Services/AlarmMgmtSWFaults.h
===================================================================
diff -u -rfd897db8177752330ad08d877e0a13620513dbdc -reb159befbbeae67205fb6b55d75743aa4d48c9b0
--- firmware/App/Services/AlarmMgmtSWFaults.h	(.../AlarmMgmtSWFaults.h)	(revision fd897db8177752330ad08d877e0a13620513dbdc)
+++ firmware/App/Services/AlarmMgmtSWFaults.h	(.../AlarmMgmtSWFaults.h)	(revision eb159befbbeae67205fb6b55d75743aa4d48c9b0)
@@ -157,6 +157,7 @@
     SW_FAULT_ID_PI_CTRL_INVALID_FEED_FORWARD_LIMIT = 126,
     SW_FAULT_ID_INVALID_TEMPERATURE_SENSOR_SELECTED3 = 127,
     SW_FAULT_ID_DIALYSATE_MIX_EXEC_INVALID_STATE = 128,
+    SW_FAULT_ID_MODE_UPDATE_INVALID_STATE = 129,
     NUM_OF_SW_FAULT_IDS
 } DD_SW_FAULT_ID_T;
 
Index: firmware/App/Services/Messaging.c
===================================================================
diff -u -r2d295ca85f19e95da42476a57ca6b4496baf980a -reb159befbbeae67205fb6b55d75743aa4d48c9b0
--- firmware/App/Services/Messaging.c	(.../Messaging.c)	(revision 2d295ca85f19e95da42476a57ca6b4496baf980a)
+++ firmware/App/Services/Messaging.c	(.../Messaging.c)	(revision eb159befbbeae67205fb6b55d75743aa4d48c9b0)
@@ -289,6 +289,7 @@
     { MSG_ID_FP_CONDUCTIVITY_SENSOR_VERSION_REQUEST,                                &testHandleConductivitySensorVersionRequest },
     { MSG_ID_DD_TEMPERATURE_SENSOR_FILTERED_TEMP_OVERRIDE_REQUEST,                  &testDDTemperatureSensorFilteredReadingsOverride },
     { MSG_ID_FP_SET_RECOVERY_VALVES_REQUEST,                                        &testIOFPSetValveRecoveryConfig },
+    { MSG_ID_FFU_SIGNAL_DD_UPDATE_AVAILABLE,                                        &handleUpdateAvailable },
 };
 
 /// Calculation for number of entries in the incoming message function handler look-up table.
@@ -768,7 +769,45 @@
     return result;
 }
 
+/*********************************************************************//**
+ * @brief
+ * The resetMicroControllerUnit function resets the MCU.
+ * @details \b Inputs: none
+ * @details \b Outputs: none
+ * @return none
+ *************************************************************************/
+void resetMicroControllerUnit( void )
+{
+    setSystemREG1_SYSECR( (0x2) << 14 );  // Reset processor
+}
 
+/*********************************************************************//**
+ * @brief
+ * The handleUpdateAvailable function handles a request from the
+ * Firmware FPGA Updater (FFU) to reset the TD firmware processor.
+ * @note If reset is successful, this function will not return.
+ * @details \b Inputs: none
+ * @details \b Outputs: TD processor soft reset if request is valid
+ * @param message Pointer to the reset request message
+ * @return FALSE if reset command rejected
+ *************************************************************************/
+BOOL handleUpdateAvailable( MESSAGE_T *message )
+{
+    BOOL result = FALSE;
+
+    // Verify payload length
+    if ( 0 == message->hdr.payloadLen )
+    {   // S/w reset of processor
+        result = TRUE;                        // Reset will prevent this from getting transmitted though
+        requestNewOperationMode( DD_MODE_UPDT );
+    }
+
+    sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_DD_2_UI, result );
+
+    return result;
+}
+
+
 /*************************************************************************
  *                       TEST SUPPORT FUNCTIONS
  *************************************************************************/
@@ -904,7 +943,7 @@
     if ( 0 == message->hdr.payloadLen )
     {   // S/w reset of processor
         result = TRUE;                        // Reset will prevent this from getting transmitted though
-        setSystemREG1_SYSECR( (0x2) << 14 );  // Reset processor
+        resetMicroControllerUnit();
     }
 
     return result;
Index: firmware/App/Services/Messaging.h
===================================================================
diff -u -r830213bc6dcc1a684610caf78c79d55f2cb41e93 -reb159befbbeae67205fb6b55d75743aa4d48c9b0
--- firmware/App/Services/Messaging.h	(.../Messaging.h)	(revision 830213bc6dcc1a684610caf78c79d55f2cb41e93)
+++ firmware/App/Services/Messaging.h	(.../Messaging.h)	(revision eb159befbbeae67205fb6b55d75743aa4d48c9b0)
@@ -68,6 +68,8 @@
 
 BOOL handleSetTDOperationMode( MESSAGE_T *message );
 BOOL handleVersionRequestMessage( MESSAGE_T *message );
+void resetMicroControllerUnit( void );
+BOOL handleUpdateAvailable( MESSAGE_T *message );
 
 // Test Support Messaging Functions **************************