Index: firmware/App/Modes/StateTxBloodPrime.c
===================================================================
diff -u -ra6d020a7797cf7fb721867eb33c8b7957da8decb -rfa48af23c2b1cf940c485ad2602fdd186e775a0e
--- firmware/App/Modes/StateTxBloodPrime.c	(.../StateTxBloodPrime.c)	(revision a6d020a7797cf7fb721867eb33c8b7957da8decb)
+++ firmware/App/Modes/StateTxBloodPrime.c	(.../StateTxBloodPrime.c)	(revision fa48af23c2b1cf940c485ad2602fdd186e775a0e)
@@ -17,6 +17,7 @@
 
 #include "AirTrap.h"
 #include "BloodFlow.h"
+#include "Buttons.h"
 #include "ModeTreatment.h"
 #include "TxParams.h"
 #include "OperationModes.h"
@@ -59,6 +60,7 @@
 
 static U32  bloodPrimeRampControlTimerCtr;                                      ///< Timer counter for determining interval for controlling BP ramp.
 static U32  bloodPrimePublishTimerCtr;                                          ///< Timer counter for determining interval for blood prime status to be published.
+static U32  lastBloodPrimeFlowRate_mL_min;                                      ///< Timer counter for determining for last blood prime status.
 
 /// Interval (in task intervals) at which to publish blood prime data to CAN bus.
 static OVERRIDE_U32_T bloodPrimePublishInterval = { BLOOD_PRIME_DATA_PUBLISH_INTERVAL, BLOOD_PRIME_DATA_PUBLISH_INTERVAL, BLOOD_PRIME_DATA_PUBLISH_INTERVAL, 0 };
@@ -231,66 +233,111 @@
     // Update blood prime volume delivered so far
     cumulativeBloodPrimeVolume_mL.data += ( getMeasuredBloodFlowRate() * BLOOD_PRIME_FLOW_INTEGRATOR );
 
-    if ( TRUE == getTestConfigStatus( TEST_CONFIG_SKIP_BLOOD_PRIME ) )
-    {
-        // If the skip blood prime is enabled, set the cumulative volume to the target blood prime volume
-        cumulativeBloodPrimeVolume_mL.data = bloodPrimeTargetVolume_mL;
-    }
-
     // Has blood prime completed?
     if ( getBloodPrimeVolume() >= bloodPrimeTargetVolume_mL )
     {
         initBloodPrime();                 // Reset blood prime so that we start anew next time we transition to this sub-mode
         setBloodIsPrimed( TRUE );         // Signal treatment mode that blood prime is completed
         signalBloodPrimeToDialysis();     // Signal treatment mode that it's time to start dialysis
+    }
+
+    else if ( getMeasuredBloodFlowRate() >= getTreatmentParameterU32( TREATMENT_PARAM_BLOOD_FLOW ) )
+    {
         result = BLOOD_PRIME_RUN_STATE;
     }
-    else
+
+    // User requested pause
+    else if ( TRUE == isStopButtonPressed() )
     {
-        // ramp blood pump on ramp interval
-        if ( ++bloodPrimeRampControlTimerCtr >= BLOOD_PRIME_RAMPING_INTERVAL )
-        {
-            U32 setBPRate = getTreatmentParameterU32( TREATMENT_PARAM_BLOOD_FLOW );
+        lastBloodPrimeFlowRate_mL_min = getMeasuredBloodFlowRate();
+        setBloodPumpTargetFlowRate(0, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
 
-            bloodPrimeRampControlTimerCtr = 0;
-            bloodPrimeRampFlowRate_mL_min += bloodPrimeRampStep_mL;
-            setBloodPumpTargetFlowRate( (U32)bloodPrimeRampFlowRate_mL_min, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
-        }
+        // Close arterial & venous valves
+        setValvePosition( H1_VALV, VALVE_POSITION_A_INSERT_EJECT );
+        setValvePosition( H19_VALV, VALVE_POSITION_A_INSERT_EJECT );
+        result = BLOOD_PRIME_PAUSED_STATE;
     }
 
+    else if ( getMeasuredBloodFlowRate() >= getTreatmentParameterU32( TREATMENT_PARAM_BLOOD_FLOW ) )
+    {
+        result = BLOOD_PRIME_RUN_STATE;
+    }
+
     return result;
 }
 
 /*********************************************************************//**
  * @brief
  * The handleBloodPrimeRunState function handles the blood prime run
  * state operations.
- * @details \b Inputs: flags
- * @details \b Outputs: flags handled
+ * @details \b Inputs: cumulativeBloodPrimevolume_mL
+ * @details \b Outputs: cumulativeBloodPrimevolume_mL
  * @return next blood prime state
  *************************************************************************/
 static BLOOD_PRIME_STATE_T handleBloodPrimeRunState( void )
 {
-    BLOOD_PRIME_STATE_T result = BLOOD_PRIME_RUN_STATE;
+   BLOOD_PRIME_STATE_T result = BLOOD_PRIME_RUN_STATE;
 
-    cumulativeBloodPrimeVolume_mL.data += ( getMeasuredBloodFlowRate() * BLOOD_PRIME_FLOW_INTEGRATOR );
+   // Update blood prime volume delivered so far
+   cumulativeBloodPrimeVolume_mL.data += ( getMeasuredBloodFlowRate() * BLOOD_PRIME_FLOW_INTEGRATOR );
 
-    return result;
+   if ( getBloodPrimeVolume() >= bloodPrimeTargetVolume_mL )
+   {
+       initBloodPrime();                 // Reset blood prime so that we start anew next time we transition to this sub-mode
+       setBloodIsPrimed( TRUE );         // Signal treatment mode that blood prime is completed
+       signalBloodPrimeToDialysis();     // Signal treatment mode that it's time to start dialysis
+   }
+
+   // User if request stop/pause
+   else if ( TRUE == isStopButtonPressed() )
+   {
+       lastBloodPrimeFlowRate_mL_min = getMeasuredBloodFlowRate();
+       // Turn pump OFF
+       setBloodPumpTargetFlowRate(0, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
+
+       // Close arterial & venous pinch valves
+       setValvePosition( H1_VALV, VALVE_POSITION_A_INSERT_EJECT );
+       setValvePosition( H19_VALV, VALVE_POSITION_A_INSERT_EJECT );
+       result = BLOOD_PRIME_PAUSED_STATE;
+   }
+
+   return result;
 }
 
 /*********************************************************************//**
  * @brief
  * The handleBloodPrimePausedState function handles the blood prime paused
  * state operations.
- * @details \b Inputs: flags
+ * @details \b Inputs: getCurrentOperationMode
  * @details \b Outputs: flags handled
  * @return none
  *************************************************************************/
 static BLOOD_PRIME_STATE_T handleBloodPrimePausedState( void )
 {
-   BLOOD_PRIME_STATE_T result = BLOOD_PRIME_PAUSED_STATE;
+    BLOOD_PRIME_STATE_T result = BLOOD_PRIME_PAUSED_STATE;
 
-   return result;
+    // Transition back to treatment
+    if ( getCurrentOperationMode() == MODE_TREA )
+    {
+        // Re-open arterial & venous valves
+        setValvePosition( H1_VALV, VALVE_POSITION_B_OPEN );
+        setValvePosition( H19_VALV, VALVE_POSITION_B_OPEN );
+
+        // Restart pump at previous flow rate
+        setBloodPumpTargetFlowRate( lastBloodPrimeFlowRate_mL_min, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
+
+        // Next state
+        if ( getMeasuredBloodFlowRate() < getTreatmentParameterU32( TREATMENT_PARAM_BLOOD_FLOW ) )
+        {
+            result = BLOOD_PRIME_RAMP_STATE;
+        }
+        else
+        {
+            result = BLOOD_PRIME_RUN_STATE;
+        }
+    }
+
+    return result;
 }
 
 /*********************************************************************//**
Index: firmware/App/Services/Messaging.c
===================================================================
diff -u -rf289a9279e8e924fd11411df6a71ac6727b800bc -rfa48af23c2b1cf940c485ad2602fdd186e775a0e
--- firmware/App/Services/Messaging.c	(.../Messaging.c)	(revision f289a9279e8e924fd11411df6a71ac6727b800bc)
+++ firmware/App/Services/Messaging.c	(.../Messaging.c)	(revision fa48af23c2b1cf940c485ad2602fdd186e775a0e)
@@ -181,7 +181,6 @@
     { MSG_ID_TD_EJECTOR_OPT_SENSOR_OVERRIDE_REQUEST,                    &testEjectorOpticalSensorOverride },
     { MSG_ID_TD_BLOOD_PRIME_VOLUME_OVERRIDE,                            &testBloodPrimeVolumeOverride },
     { MSG_ID_TD_BLOOD_PRIME_PUBLISH_INTERVAL_OVERRIDE_REQUEST,          &testBloodPrimePublishIntervalOverride },
-    { MSG_ID_TD_ENABLE_VENOUS_BUBBLE_ALARM,                             &testEnableVenousBubbleAlarm },
 };
 
 #define NUM_OF_FUNCTION_HANDLERS (sizeof(MSG_FUNCTION_HANDLER_LOOKUP) / sizeof(MSG_HANDLER_LOOKUP_T))