Index: firmware/App/Modes/ModeTreatment.c
===================================================================
diff -u -rd3ae2d91603ae6d2d25b9abdb220cc144cf90692 -r054fa08b67ed2a31f7848b179fbcd1b4da501b0f
--- firmware/App/Modes/ModeTreatment.c	(.../ModeTreatment.c)	(revision d3ae2d91603ae6d2d25b9abdb220cc144cf90692)
+++ firmware/App/Modes/ModeTreatment.c	(.../ModeTreatment.c)	(revision 054fa08b67ed2a31f7848b179fbcd1b4da501b0f)
@@ -43,8 +43,13 @@
 #define MAX_UF_RATE_ML_MIN                      ( (F32)2500 / (F32)MIN_PER_HOUR )           ///< Maximum ultrafiltration rate (in mL/min).
 #define MAX_DIALYSATE_VOLUME_ML                 ( 180 * ML_PER_LITER )                      ///< Maximum dialysate volume (in mL).
 
+#define PREVENT_UF_VOL_CHANGE_IF_NEARLY_DONE_SEC    ( 10 * SEC_PER_MIN )                    ///< Prevent UF volume change if treatment within this much time from end of treatment (in seconds).
+
 #define TREATMENT_TIME_DATA_PUB_INTERVAL        ( MS_PER_SECOND / TASK_GENERAL_INTERVAL )   ///< Interval (ms/task time) at which the treatment time & state data is published on the CAN bus
 
+#define CALC_ELAPSED_TREAT_TIME_IN_SECS()     ( treatmentTimeMS / MS_PER_SECOND )           ///< Macro to calculate the elapsed treatment time in seconds.
+#define CALC_TREAT_TIME_REMAINING_IN_SECS()   ( (S32)presTreatmentTimeSecs - (S32)( treatmentTimeMS / MS_PER_SECOND ) )   ///< Macro to calculate the remaining treatment time in seconds.
+
 // ********** private data **********
 
 static TREATMENT_STATE_T currentTreatmentState;                 ///< Current state (sub-mode) of treatment mode.
@@ -356,6 +361,7 @@
 BOOL verifyTreatmentDurationSettingChange( U32 treatmentTime )
 {
     BOOL result = FALSE;
+    REQUEST_REJECT_REASON_CODE_T rejectReason = REQUEST_REJECT_REASON_NONE;
     S32 timeDiff = 0;
     F32 rateDiff = 0.0;
     OP_MODE currMode = getCurrentOperationMode();
@@ -376,8 +382,30 @@
             pendingTreatmentTimeChange = treatmentTime;     // min
             timeDiff = treatmentTime - ( (U32)( (F32)presTreatmentTimeSecs / (F32)SEC_PER_MIN ) + 1 );
         }
+        else
+        {
+            if ( treatmentTime > MAX_TREATMENT_TIME_MINUTES )
+            {
+                rejectReason = REQUEST_REJECT_REASON_TREATMENT_TIME_OUT_OF_RANGE;
+            }
+            else
+            {
+                rejectReason = REQUEST_REJECT_REASON_DIAL_VOLUME_OUT_OF_RANGE;
+            }
+        }
     }
-    sendChangeUFSettingsResponse( result, pendingUFVolumeChange, pendingTreatmentTimeChange, pendingUFRateChange, timeDiff, rateDiff );
+    else
+    {
+        if ( MODE_TREA == currMode )
+        {
+            rejectReason = REQUEST_REJECT_REASON_TREATMENT_TIME_OUT_OF_RANGE;
+        }
+        else
+        {
+            rejectReason = REQUEST_REJECT_REASON_INVALID_TREATMENT_STATE;
+        }
+    }
+    sendChangeUFSettingsResponse( result, rejectReason, pendingUFVolumeChange, pendingTreatmentTimeChange, pendingUFRateChange, timeDiff, rateDiff );
 
     return result;
 }
@@ -396,12 +424,16 @@
 BOOL verifyUFSettingsChange( F32 uFVolume, UF_ADJ_T adjustment )
 {
     BOOL result = FALSE;
+    REQUEST_REJECT_REASON_CODE_T rejectReason = REQUEST_REJECT_REASON_NONE;
     S32 timeDiff = 0;
     F32 rateDiff = 0.0;
     OP_MODE currMode = getCurrentOperationMode();
 
-    // check if we are in an appropriate treatment state for settings adjustment
-    if ( ( MODE_TREA == currMode ) && ( currentTreatmentState > TREATMENT_START_STATE ) && ( currentTreatmentState < TREATMENT_DIALYSIS_END_STATE ) )
+    // check if we are in an appropriate treatment state for settings adjustment  // TODO - we cannot be within TBD min from end of treatment in order to allow UF volume change
+    if ( ( MODE_TREA == currMode ) &&
+         ( currentTreatmentState > TREATMENT_START_STATE ) &&
+         ( currentTreatmentState < TREATMENT_DIALYSIS_END_STATE ) &&
+         ( CALC_TREAT_TIME_REMAINING_IN_SECS() < PREVENT_UF_VOL_CHANGE_IF_NEARLY_DONE_SEC ) )
     {
         // TODO - verify not too close to end of treatment for settings change
         DIALYSIS_STATE_T currDialysisState = getDialysisState();
@@ -438,6 +470,18 @@
                 pendingTreatmentTimeChange = trtTime;
                 timeDiff = trtTime - ( (U32)( (F32)presTreatmentTimeSecs / (F32)SEC_PER_MIN ) + 1 );
             }
+            else
+            {
+                if ( trtTime > MAX_TREATMENT_TIME_MINUTES )
+                {
+                    rejectReason = REQUEST_REJECT_REASON_TREATMENT_TIME_OUT_OF_RANGE;
+                }
+                else
+                {
+                    rejectReason = REQUEST_REJECT_REASON_DIAL_VOLUME_OUT_OF_RANGE;
+                }
+
+            }
         }
         else
         {   // UF Rate is adjusted then
@@ -451,10 +495,30 @@
                 pendingTreatmentTimeChange = trtTime;
                 rateDiff = ( uFRate - presUFRate );
             }
+            else
+            {
+                rejectReason = REQUEST_REJECT_REASON_UF_RATE_OUT_OF_RANGE;
+            }
         }
     }
+    else
+    {
+        if ( MODE_TREA == currMode )
+        {
+            rejectReason = REQUEST_REJECT_REASON_TREATMENT_TIME_OUT_OF_RANGE;
+        }
+        else if ( ( currentTreatmentState <= TREATMENT_START_STATE ) ||
+                  ( currentTreatmentState >= TREATMENT_DIALYSIS_END_STATE ) )
+        {
+            rejectReason = REQUEST_REJECT_REASON_INVALID_TREATMENT_STATE;
+        }
+        else
+        {
+            rejectReason = REQUEST_REJECT_REASON_TREATMENT_TOO_CLOSE_TO_FINISHED;
+        }
+    }
     // respond to UF settings change request
-    sendChangeUFSettingsResponse( result, pendingUFVolumeChange, pendingTreatmentTimeChange, pendingUFRateChange, timeDiff, rateDiff );
+    sendChangeUFSettingsResponse( result, rejectReason, pendingUFVolumeChange, pendingTreatmentTimeChange, pendingUFRateChange, timeDiff, rateDiff );
 
     return result;
 }
@@ -506,3 +570,57 @@
 
     return result;
 }
+
+/*********************************************************************//**
+ * @brief
+ * The verifyBloodAndDialysateRateSettingsChange function verifies the \n
+ * user blood & dialysate flow rate settings change.
+ * @details
+ * Inputs : none
+ * Outputs : none
+ * @param bloodRate : Proposed new blood flow rate (in mL/min).
+ * @param dialRate : Proposed new dialysate flow rate (in mL/min).
+ * @return TRUE if new blood & dialysate rate settings are valid, FALSE if not.
+ *************************************************************************/
+BOOL verifyBloodAndDialysateRateSettingsChange( U32 bloodRate, U32 dialRate )
+{
+    BOOL result = FALSE;
+    REQUEST_REJECT_REASON_CODE_T rejectReason = REQUEST_REJECT_REASON_NONE;
+    OP_MODE currMode = getCurrentOperationMode();
+
+    // check if we are in treatment mode for settings change
+    if ( MODE_TREA == currMode )
+    {
+        U32 dialVolume = dialRate * ( (U32)( (F32)presTreatmentTimeSecs / (F32)SEC_PER_MIN ) + 1 );   // in mL
+
+        // validate new rates
+        if ( ( bloodRate >= MIN_BLOOD_FLOW_RATE ) && ( bloodRate <= MAX_BLOOD_FLOW_RATE ) &&
+             ( dialRate >= MIN_DIAL_IN_FLOW_RATE ) && ( dialRate <= MAX_DIAL_IN_FLOW_RATE ) &&
+             ( dialVolume <= MAX_DIALYSATE_VOLUME_ML ) )
+        {
+            result = TRUE;
+            // set to new rates
+            presBloodFlowRate = bloodRate;
+            presDialysateFlowRate = dialRate;
+            setDialysisParams( presBloodFlowRate, presDialysateFlowRate, presMaxUFVolumeML, presUFRate );
+        }
+        else
+        {
+            if ( ( bloodRate < MIN_BLOOD_FLOW_RATE ) || ( bloodRate > MAX_BLOOD_FLOW_RATE ) )
+            {
+                rejectReason = REQUEST_REJECT_REASON_BLOOD_FLOW_OUT_OF_RANGE;
+            }
+            else if ( ( dialRate < MIN_DIAL_IN_FLOW_RATE ) || ( dialRate > MAX_DIAL_IN_FLOW_RATE ) )
+            {
+                rejectReason = REQUEST_REJECT_REASON_DIAL_FLOW_OUT_OF_RANGE;
+            }
+            else
+            {
+                rejectReason = REQUEST_REJECT_REASON_DIAL_VOLUME_OUT_OF_RANGE;
+            }
+        }
+    }
+    sendChangeBloodDialysateRateChangeResponse( result, (U32)rejectReason, bloodRate, dialRate );
+
+    return result;
+}