Index: firmware/App/Modes/ModeGenDialysate.c
===================================================================
diff -u -r977f03e20990ed5579160b9b927df1c0f2428101 -rc51c9d66062c27c588006850550b412ea7dd5144
--- firmware/App/Modes/ModeGenDialysate.c	(.../ModeGenDialysate.c)	(revision 977f03e20990ed5579160b9b927df1c0f2428101)
+++ firmware/App/Modes/ModeGenDialysate.c	(.../ModeGenDialysate.c)	(revision c51c9d66062c27c588006850550b412ea7dd5144)
@@ -59,6 +59,7 @@
 #define LINEAR_SLOPE_FACTOR                             -0.0029F                                    ///< Slope factor used in adjusted dialysate temperature linear calculation for high Qds
 #define LINEAR_INTERCEPT_FACTOR                         3.47F                                       ///< Intercept factor used in adjusted dialysate temperature linear calculation for high Qds
 #define LOW_DIAL_FLOW_RATE                              150.0F                                      ///< Dialysate flow rate lesser than 150 considered to be low Qds.
+#define SPENT_CHAMBER_FILL_MAX_COUNT                    7                                           ///< Total number of spent chamber fill allowed.
 
 //Testing
 #define DELAY_BC_SWITCHING_AT_START_UP          ( 10 * MS_PER_SECOND )                              ///< Provide a balancing chamber switching start up delay to stabilize pump speed etc.,
@@ -70,7 +71,7 @@
 
 // ********** private data **********
 
-static DD_GEND_MODE_STATE_T genDialysateState = DD_GEND_STATE_START;                        ///< Currently active gen dialysate state.
+static DD_GEND_MODE_STATE_T genDialysateState;                                              ///< Currently active gen dialysate state.
 static OVERRIDE_F32_T targetHydChamberFluidTemp;                                            ///< Target hydraulics chamber fluid temperature.
 static OVERRIDE_U32_T isDialDeliveryInProgress;                                             ///< To indicate dialysate started delivering to dialyzer for treatment (overrideable)
 static OVERRIDE_U32_T isDialysateGoodtoDeliver;                                             ///< Flag indicating whether ready to deliver dialysate or not.
@@ -90,6 +91,8 @@
 static DD_GEND_MODE_STATE_T handleGenDDialysateDeliveryPauseState( void );
 static DD_GEND_MODE_STATE_T handleGenDSpentChamberFillState(void);
 static DD_GEND_MODE_STATE_T handleGenDIsolatedUFState( void );
+static F32 getGenDialysateTargetTemperature( void );
+static void calculateTargetDialysateTemp( void );
 static void checkDialysateTemperature( void );
 static void publishGenDialysateModeData( void );
 
@@ -195,12 +198,13 @@
             break;
 
         case DD_GEND_DIALYSATE_BYPASS_STATE:
+            //Close all balancing chamber valves
+            valveControlForBCClosedState();
             //Previous state
             setValveState( DD_M4_VALV, VALVE_STATE_OPEN );
-            // Get the target temperature from TD
-            //targetHydChamberFluidTemp.data = getTDTargetDialysateTemperature();
-            calculateTargetDialysateTemp();
+
             // Turn on the primary heater
+            calculateTargetDialysateTemp();
             setHeaterTargetTemperature( D5_HEAT, getGenDialysateTargetTemperature() );
             startHeater( D5_HEAT );
 
@@ -224,8 +228,8 @@
         case DD_GEND_DIALYSATE_DELIVERY_STATE:
             //Previous state
             setValveState( DD_M4_VALV, VALVE_STATE_OPEN );
-            // Get the target temperature from TD
-            //targetHydChamberFluidTemp.data = getTDTargetDialysateTemperature();
+
+            // Turn on the primary heater
             calculateTargetDialysateTemp();
             setHeaterTargetTemperature( D5_HEAT, getGenDialysateTargetTemperature() );
             startHeater( D5_HEAT );
@@ -242,6 +246,28 @@
             setValveState( D40_VALV, VALVE_STATE_OPEN );    // VDO
             break;
 
+        case DD_GEND_SPENT_CHAMBER_FILL_STATE:
+            //Close all balancing chamber valves
+            valveControlForBCClosedState();
+            transitionToSpentChamberFill();
+
+            //Set valves and actuators
+            setValveState( DD_M4_VALV, VALVE_STATE_OPEN );
+
+            calculateTargetDialysateTemp();
+            // Turn on the primary heater
+            setHeaterTargetTemperature( D5_HEAT, getGenDialysateTargetTemperature() );
+            startHeater( D5_HEAT );
+
+            setValveState( D14_VALV, VALVE_STATE_OPEN );
+            setDialysatePumpTargetRPM( D12_PUMP, FRESH_DIAL_PUMP_INITIAL_RPM, TRUE );
+            setValveState( D53_VALV, VALVE_STATE_OPEN );   // Drain valve
+            setValveState( D35_VALV, VALVE_STATE_CLOSED );  // VDI
+            setValveState( D40_VALV, VALVE_STATE_CLOSED );  // VDO
+            setValveState( D34_VALV, VALVE_STATE_OPEN );    // Bypass valve
+            setDialysatePumpTargetRPM( D48_PUMP, SPENT_DIAL_PUMP_FILL_RPM, TRUE );
+            break;
+
         case DD_GEND_DIALYSATE_DELIVERY_PAUSE:
             // stop the motor during pause conditions
             signalDialysatePumpHardStop( D12_PUMP );
@@ -387,7 +413,7 @@
  * @details \b Outputs: Adjusted Target temperature
  * @return none.
  *************************************************************************/
-void calculateTargetDialysateTemp( void )
+static void calculateTargetDialysateTemp( void )
 {
     // Get the dialysate flow rate from TD
     F32 dialFlowrate = getTDDialysateFlowrate();
@@ -438,7 +464,8 @@
  *************************************************************************/
 static DD_GEND_MODE_STATE_T handleGenDDialysateBypassState( void )
 {
-    DD_GEND_MODE_STATE_T state  = DD_GEND_DIALYSATE_BYPASS_STATE;
+    DD_GEND_MODE_STATE_T state      = DD_GEND_DIALYSATE_BYPASS_STATE;
+    LEVEL_STATE_T spentChamberLevel = getLevelStatus( D46_LEVL );
 
     //Testing
     if ( TRUE == delayBypassStateFlag )
@@ -454,6 +481,14 @@
         execBalancingChamberControl();
     }
 
+#ifdef __SPENT_CHAMBER_FILL__
+    if ( LEVEL_STATE_LOW == spentChamberLevel )
+    {
+        setModeGenDStateTransition( DD_GEND_SPENT_CHAMBER_FILL_STATE );
+        isDialDeliveryInProgress.data = FALSE;
+        state = DD_GEND_SPENT_CHAMBER_FILL_STATE;
+    }
+#endif
     //if the produced dialysate is good and TD asks for dialysate delivery
     //move to next state
     if ( ( TRUE == getDialGoodToDeliverStatus() ) && ( FALSE == getTDDialyzerBypass() ) )
@@ -476,14 +511,9 @@
  *************************************************************************/
 static DD_GEND_MODE_STATE_T handleGenDDialysateDeliveryState( void )
 {
-    DD_GEND_MODE_STATE_T state  = DD_GEND_DIALYSATE_DELIVERY_STATE;
+    DD_GEND_MODE_STATE_T state      = DD_GEND_DIALYSATE_DELIVERY_STATE;
+    LEVEL_STATE_T spentChamberLevel = getLevelStatus( D46_LEVL );
 
-    //Execute balancing chamber
-    execBalancingChamberControl();
-
-    //Execute ultrafiltration
-    execUFControl();
-
     // if TD asks for bypass or dialysate is not good to deliver
     //transition to bypass dialystate state
     if ( ( FALSE == getDialGoodToDeliverStatus() ) || ( TRUE == getTDDialyzerBypass() ) )
@@ -492,7 +522,23 @@
         isDialDeliveryInProgress.data = FALSE;
         state = DD_GEND_DIALYSATE_BYPASS_STATE;
     }
+#ifdef __SPENT_CHAMBER_FILL__
+    else if ( LEVEL_STATE_LOW == spentChamberLevel )
+    {
+        setModeGenDStateTransition( DD_GEND_SPENT_CHAMBER_FILL_STATE );
+        isDialDeliveryInProgress.data = FALSE;
+        state = DD_GEND_SPENT_CHAMBER_FILL_STATE;
+    }
+#endif
+    else
+    {
+        //Execute balancing chamber
+        execBalancingChamberControl();
 
+        //Execute ultrafiltration
+        execUFControl();
+    }
+
     return state;
 }
 /*********************************************************************//**
@@ -508,9 +554,11 @@
     DD_GEND_MODE_STATE_T state  = DD_GEND_SPENT_CHAMBER_FILL_STATE;
 
     LEVEL_STATE_T spentChamberLevel = getLevelStatus( D46_LEVL );
+    U32 totalSpentChamberFill       = getTotalSpentChamberFillCounts();
 
-    // High level is met
-    if ( LEVEL_STATE_HIGH == spentChamberLevel )
+    // High level is met or total fill count exceeded
+    if ( ( LEVEL_STATE_HIGH == spentChamberLevel ) ||
+         ( totalSpentChamberFill >= SPENT_CHAMBER_FILL_MAX_COUNT ) )
     {
         setModeGenDStateTransition( DD_GEND_DIALYSATE_BYPASS_STATE );
         isDialDeliveryInProgress.data = FALSE;
@@ -678,7 +726,7 @@
  * @details \b Outputs: none
  * @return the target dialysate temperature for the treatment.
  *************************************************************************/
-F32 getGenDialysateTargetTemperature( void )
+static F32 getGenDialysateTargetTemperature( void )
 {
     F32 temp = getF32OverrideValue( &targetHydChamberFluidTemp );