Index: firmware/App/Modes/ModeStandby.c
===================================================================
diff -u -r79c2105d7ec35f3caeb977f6e2cc1b494853d211 -rdb8ff28e816a37e033e36b76ab5949be78114125
--- firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision 79c2105d7ec35f3caeb977f6e2cc1b494853d211)
+++ firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision db8ff28e816a37e033e36b76ab5949be78114125)
@@ -23,6 +23,7 @@
 #include "ModeTxParams.h"
 #include "ModeStandby.h"
 #include "OperationModes.h"
+#include "SystemCommTD.h"
 
 /**
  *  @addtogroup TDStandbyMode
@@ -71,7 +72,7 @@
 
     // Re-initialize when transitioning to standby mode
     initStandbyMode();
-    initDDInterface();
+    resetDDInterface();
     setCurrentSubState( NO_SUB_STATE );
 
     // Set user alarm recovery actions allowed in this mode
@@ -203,7 +204,7 @@
 static TD_STANDBY_STATE_T handleStandbyModeWaitForTreatmentState( void )
 {
     TD_STANDBY_STATE_T state     = STANDBY_WAIT_FOR_TREATMENT_STATE;
-//    DG_OP_MODE_T dgOperationMode = getDDOpMode();
+    DD_OP_MODE_T ddOperationMode = getDDOpMode();
 
 //    switch ( dgOperationMode )
 //    {
@@ -293,6 +294,16 @@
             {
                 rejReason = REQUEST_REJECT_REASON_NOT_ALLOWED_IN_CURRENT_MODE;
             }
+            // Verify DD is communicating with HD
+            else if ( isDDCommunicating() != TRUE )
+            {
+                rejReason = REQUEST_REJECT_REASON_DD_COMM_LOST;
+            }
+            // Verify DD is not busy
+            else if ( ( DD_MODE_STAN != getDDOpMode() ) || ( DD_STANDBY_MODE_STATE_IDLE != getDDSubMode() ) ) // || ( isDDPOSTPassed() != TRUE ) )
+            {
+                rejReason = REQUEST_REJECT_REASON_DD_NOT_IN_STANDBY_IDLE_STATE;
+            }
             else
             {
                 // If request to start treatment not rejected, set flag to initiate treatment workflow
Index: firmware/App/Modes/ModeTxParams.c
===================================================================
diff -u -raa6d45143096dfab776ce2ed7c775cfe2dd6db18 -rdb8ff28e816a37e033e36b76ab5949be78114125
--- firmware/App/Modes/ModeTxParams.c	(.../ModeTxParams.c)	(revision aa6d45143096dfab776ce2ed7c775cfe2dd6db18)
+++ firmware/App/Modes/ModeTxParams.c	(.../ModeTxParams.c)	(revision db8ff28e816a37e033e36b76ab5949be78114125)
@@ -105,7 +105,7 @@
 
 /// Treatment parameter properties (types, ranges and defaults).
 const TREATMENT_PARAMS_PROPERTIES_T TREAT_PARAMS_PROPERTIES[ NUM_OF_TREATMENT_PARAMS ] =
-{
+{   //         type                min           max         default
     { CRITICAL_DATA_TYPE_U32, {.uInt=50},   {.uInt=500},  {.uInt=50}   }, // TREATMENT_PARAM_BLOOD_FLOW
     { CRITICAL_DATA_TYPE_U32, {.uInt=50},   {.uInt=600},  {.uInt=50}   }, // TREATMENT_PARAM_DIALYSATE_FLOW
     { CRITICAL_DATA_TYPE_U32, {.uInt=60},   {.uInt=480},  {.uInt=60}   }, // TREATMENT_PARAM_TREATMENT_DURATION
@@ -114,7 +114,7 @@
     { CRITICAL_DATA_TYPE_U32, {.uInt=0},    {.uInt=0},    {.uInt=0}    }, // TREATMENT_PARAM_HEPARIN_TYPE
     { CRITICAL_DATA_TYPE_U32, {.uInt=0},    {.uInt=2},    {.uInt=0}    }, // TREATMENT_PARAM_ACID_CONCENTRATE
     { CRITICAL_DATA_TYPE_U32, {.uInt=0},    {.uInt=0},    {.uInt=0}    }, // TREATMENT_PARAM_BICARB_CONCENTRATE
-    { CRITICAL_DATA_TYPE_U32, {.uInt=0},    {.uInt=5},    {.uInt=0}    }, // TREATMENT_PARAM_DIALYZER_TYPE
+    { CRITICAL_DATA_TYPE_U32, {.uInt=0},    {.uInt=6},    {.uInt=0}    }, // TREATMENT_PARAM_DIALYZER_TYPE
     { CRITICAL_DATA_TYPE_U32, {.uInt=0},    {.uInt=60},   {.uInt=0}    }, // TREATMENT_PARAM_BP_MEAS_INTERVAL
     { CRITICAL_DATA_TYPE_U32, {.uInt=100},  {.uInt=300},  {.uInt=200}  }, // TREATMENT_PARAM_RINSEBACK_FLOW_RATE
     { CRITICAL_DATA_TYPE_U32, {.uInt=200},  {.uInt=400},  {.uInt=300}  }, // TREATMENT_PARAM_RINSEBACK_VOLUME
@@ -701,11 +701,12 @@
 BOOL signalUserConfirmationOfTreatmentParameters( MESSAGE_T *message )
 {
     BOOL result = FALSE;
-    BOOL confirmed = FALSE;
 
     // Verify message payload length is valid
     if ( sizeof( BOOL ) == message->hdr.payloadLen )
     {
+        BOOL confirmed = FALSE;
+
         memcpy( &confirmed, message->payload, sizeof( BOOL ) );
         if ( ( MODE_TPAR == getCurrentOperationMode() ) && ( TD_TREATMENT_PARAMS_MODE_STATE_WAIT_4_UI_2_CONFIRM == currentTreatmentParamsState ) )
         {
Index: firmware/App/Services/DDInterface.c
===================================================================
diff -u -r036a75d76ab01912646a480b935d97187a231a19 -rdb8ff28e816a37e033e36b76ab5949be78114125
--- firmware/App/Services/DDInterface.c	(.../DDInterface.c)	(revision 036a75d76ab01912646a480b935d97187a231a19)
+++ firmware/App/Services/DDInterface.c	(.../DDInterface.c)	(revision db8ff28e816a37e033e36b76ab5949be78114125)
@@ -67,23 +67,14 @@
 {
     U32 i;
 
-    // NOTE: the active reservoir is set to reservoir 1 since DG will send active reservoir 1 as active on power up
-    ddStarted                               = FALSE;
     ddCurrentOpMode                         = DD_MODE_INIT;
     ddSubMode                               = 0;
     dialysatePressure                       = 0.0F;
-    ddStartCommandSent                      = FALSE;
 
     ddOpModeDataFreshFlag                   = FALSE;
     ddDialysatePressureFreshFlag            = FALSE;
 
-    dialysateDeliveryCmdSet.start           = FALSE;
-    dialysateDeliveryCmdSet.dialRate        = 0.0F;
-    dialysateDeliveryCmdSet.ufRate          = 0.0F;
-    dialysateDeliveryCmdSet.dialTemp        = 0.0F;
-    dialysateDeliveryCmdSet.bypassDialyzer  = TRUE;
-    dialysateDeliveryCmdSet.acidType        = 0;
-    dialysateDeliveryCmdSet.bicarbType      = 0;
+    resetDDInterface();
 
     // initialize DD command response
     for ( i = 0; i < NUM_OF_DD_COMMANDS; i++ )
@@ -96,6 +87,28 @@
 //    initPersistentAlarm( ALARM_ID_TD_DD_NEW_OPERATION_MODE_MESSAGE_NOT_RECEIVE, DD_DATA_FRESHNESS_TIMEOUT_MS, DD_DATA_FRESHNESS_TIMEOUT_MS );
 }
 
+/*********************************************************************//**
+ * @brief
+ * The resetDDInterface function resets the DDInterface unit before starting
+ * a new treatment work flow.
+ * @details \b Inputs: none
+ * @details \b Outputs: DDInterface unit reset.
+ * @return none
+ *************************************************************************/
+void resetDDInterface( void )
+{
+    ddStarted                               = FALSE;
+    ddStartCommandSent                      = FALSE;
+
+    dialysateDeliveryCmdSet.start           = FALSE;
+    dialysateDeliveryCmdSet.dialRate        = 0.0F;
+    dialysateDeliveryCmdSet.ufRate          = 0.0F;
+    dialysateDeliveryCmdSet.dialTemp        = 0.0F;
+    dialysateDeliveryCmdSet.bypassDialyzer  = TRUE;
+    dialysateDeliveryCmdSet.acidType        = 0;
+    dialysateDeliveryCmdSet.bicarbType      = 0;
+}
+
 /**********************************************************************//**
  * @brief
  * The checkDGDataFreshness function checks the freshness of data coming from
@@ -293,6 +306,7 @@
     dialysateDeliveryCmdSet.bicarbType     = (U32)bicarb;
 
     sendMessage( MSG_ID_DD_GEN_DIALYSATE_REQUEST_DATA, COMM_BUFFER_OUT_CAN_TD_2_DD, (U08*)(&dialysateDeliveryCmdSet), sizeof( DIALYSATE_DELIVERY_REQ_PAYLOAD_T ) );
+    ddStartCommandSent = TRUE;
 }
 
 /*********************************************************************//**
Index: firmware/App/Services/DDInterface.h
===================================================================
diff -u -r036a75d76ab01912646a480b935d97187a231a19 -rdb8ff28e816a37e033e36b76ab5949be78114125
--- firmware/App/Services/DDInterface.h	(.../DDInterface.h)	(revision 036a75d76ab01912646a480b935d97187a231a19)
+++ firmware/App/Services/DDInterface.h	(.../DDInterface.h)	(revision db8ff28e816a37e033e36b76ab5949be78114125)
@@ -44,6 +44,7 @@
 // ********** public function prototypes **********
 
 void initDDInterface( void );
+void resetDDInterface( void );
 
 void execDDInterfaceMonitor( void );