Index: firmware/App/Services/TDInterface.c
===================================================================
diff -u -rbd522c8ffdf75130571e5b6a79d1b1d6acd78b1c -r67453852a25077d0da103dca88449ee79d628680
--- firmware/App/Services/TDInterface.c	(.../TDInterface.c)	(revision bd522c8ffdf75130571e5b6a79d1b1d6acd78b1c)
+++ firmware/App/Services/TDInterface.c	(.../TDInterface.c)	(revision 67453852a25077d0da103dca88449ee79d628680)
@@ -95,6 +95,8 @@
 static U32 tdSubMode;                                                      ///< Current state (sub-mode) of current TD operation mode.
 static BOOL tdDialyzerBypass;                                              ///< TD dialyzer bypass
 static BOOL tdOpModeDataFreshFlag = FALSE;                                 ///< Flag to signal/process fresh TD op mode data
+static BOOL chamberHValveOpen;                                             ///< Chamber H vent valve open status
+static BOOL primeFluidDiscardStart;                                        ///< Priming fluid discard start status
 
 static OVERRIDE_F32_T tdDialysateFlowrate;                                 ///< TD Dialysate flow rate
 static OVERRIDE_F32_T tdUFRate;                                            ///< TD ultrafiltration rate
@@ -238,6 +240,34 @@
 
 /*********************************************************************//**
  * @brief
+ * The setChamberHValveStatus function sets the requested Chamber H vent
+ * valve open state, used to open chamber H valve to depressurize.
+ * @details \b Inputs: none
+ * @details \b Outputs: chamberHValveOpen
+ * @param flag TRUE to request the Chamber H vent valve open, FALSE to close it
+ * @return none
+ *************************************************************************/
+void setChamberHValveStatus( BOOL flag )
+{
+    chamberHValveOpen = flag;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The setprimeFluidDiscardStatus function sets the requested priming fluid
+ * discard state, used to discard priming fluid.
+ * @details \b Inputs: none
+ * @details \b Outputs: primeFluidDiscardStart
+ * @param flag TRUE to request priming fluid discard start, FALSE to stop it
+ * @return none
+ *************************************************************************/
+void setprimeFluidDiscardStatus( BOOL flag )
+{
+    primeFluidDiscardStart = flag;
+}
+
+/*********************************************************************//**
+ * @brief
  * The setTDOpMode function sets the latest TD operating mode reported by
  * the TD (called by TD published message handler).
  * @details \b Alarm: ALARM_ID_DD_SOFTWARE_FAULT if reported TD mode is invalid.
@@ -364,6 +394,32 @@
 
 /*********************************************************************//**
  * @brief
+ * The getChamberHValveStatus function returns the current Chamber H vent
+ * valve open request status.
+ * @details \b Inputs: chamberHValveOpen
+ * @details \b Outputs: none
+ * @return TRUE if Chamber H vent valve open is requested, FALSE if not
+ *************************************************************************/
+BOOL getChamberHValveStatus( void )
+{
+    return chamberHValveOpen;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The getprimeFluidDiscardStatus function returns the current priming fluid
+ * discard request status.
+ * @details \b Inputs: primeFluidDiscardStart
+ * @details \b Outputs: none
+ * @return TRUE if priming fluid discard is requested, FALSE if not
+ *************************************************************************/
+BOOL getprimeFluidDiscardStatus( void )
+{
+    return primeFluidDiscardStart;
+}
+
+/*********************************************************************//**
+ * @brief
  * The getTDTargetDialysateTemperature function gets the latest TD
  * target dialysate temperature rate.
  * @details \b Inputs: tdDialysateTemp
@@ -609,7 +665,35 @@
     return result;
 }
 
+/*********************************************************************//**
+ * @brief
+ * The handlePrimeDataRequestMsg function handles a prime data request
+ * from TD, updates Chamber H vent valve and priming fluid discard requests.
+ * @details \b Inputs: none
+ * @details \b Outputs: message handled
+ * @param message a pointer to the message to handle
+ * @return TRUE if message is sucessfully parsed, FALSE if not.
+ *************************************************************************/
+BOOL handlePrimeDataRequestMsg( MESSAGE_T *message )
+{
+    BOOL result = FALSE;
 
+    if ( message->hdr.payloadLen == sizeof( PRIME_DATA_REQ_PAYLOAD_T ) )
+    {
+        PRIME_DATA_REQ_PAYLOAD_T payload;
+
+        memcpy( &payload, message->payload, sizeof( PRIME_DATA_REQ_PAYLOAD_T ) );
+
+        setChamberHValveStatus( payload.chamberHValveOpen );
+        setprimeFluidDiscardStatus( payload.primeFluidDiscardStart );
+    }
+
+    sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_DD_2_TD, result );
+
+    return result;
+}
+
+
 /*************************************************************************
  *                       TEST SUPPORT FUNCTIONS
  *************************************************************************/