Index: firmware/App/Controllers/BloodFlow.c
===================================================================
diff -u -r04c811aa50770c85837d89b7e661b66f33decfb9 -rfbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3
--- firmware/App/Controllers/BloodFlow.c	(.../BloodFlow.c)	(revision 04c811aa50770c85837d89b7e661b66f33decfb9)
+++ firmware/App/Controllers/BloodFlow.c	(.../BloodFlow.c)	(revision fbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3)
@@ -78,7 +78,7 @@
 
 #define BP_RAMP_STEP_SPEED_RPM              50                                      ///< Blood pump ramp step size (in RPM).
 
-#define BP_ML_PER_ROTOR_REV                 13.75F                                  ///< Blood pump volume (mL) per rotor revolution.
+#define BP_ML_PER_ROTOR_REV                 12.26F                                  ///< Blood pump volume (mL) per rotor revolution.
 #define BP_FLOW_ALPHA_Y_INTERCEPT           1.00F                                   ///< Y intercept used for alpha flow coefficient calculation.
 #define BP_FLOW_WEAR_A_TERM                 0.000000F                               ///< A term used for wear portion of alpha flow coefficient.
 #define BP_FLOW_WEAR_B_TERM                 0.000000F                               ///< B term used for wear portion of alpha flow coefficient.
@@ -420,13 +420,13 @@
  * @brief
  * The getBloodPumpRotorCount function returns the current count for the
  * blood pump rotor revolution counter.
- * @details \b Inputs: bloodPumpRotorCounter
- * @details \b Outputs: none
+ * @details \b Inputs: bloodPumpRotorCounter,getPeristalticPumpRotorRevs
+ * @details \b Outputs: bloodPumpRotorCounter
  * @return h4RotorRevsCounter
  *************************************************************************/
 static U32 getBloodPumpRotorCount( void )
 {
-    U32 h4RotorRevsCounter     = (U32)getH4RotorRevsCounter();
+    U32 h4RotorRevsCounter     = getPeristalticPumpRotorRevs();
     bloodPumpRotorCounter.data = h4RotorRevsCounter;
 
     if ( OVERRIDE_KEY == bloodPumpRotorCounter.override )
Index: firmware/App/Drivers/PeristalticPump.c
===================================================================
diff -u -r395522dffef1348e176564925656012f529c1910 -rfbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3
--- firmware/App/Drivers/PeristalticPump.c	(.../PeristalticPump.c)	(revision 395522dffef1348e176564925656012f529c1910)
+++ firmware/App/Drivers/PeristalticPump.c	(.../PeristalticPump.c)	(revision fbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3)
@@ -19,6 +19,7 @@
 #include "FpgaTD.h"
 #include "Messaging.h"
 #include "PeristalticPump.h"
+#include "Utilities.h"
 
 /**
  *  @addtogroup PeristalticPump
@@ -51,6 +52,8 @@
 static F32 pumpMeasRotSpeedRPM;                                                 ///< Latest measured pump rotor speed (in RPM).
 static BOOL pumpHomeInProgress;                                                 ///< Flag indicates a pump home operation is in progress.
 static BOOL pumpHomeLowSignalSeen;                                              ///< Flag indicates a pump home operation has seen a "not home" signal.
+static U16 rotorRevsPrev;                                                       ///< Previous FPGA rotor revs counter value.
+static U32 rotorRevsAccum;                                                      ///< Accumulated rotor revolutions count.
 
 // ********** private function prototypes **********
 
@@ -70,6 +73,9 @@
     pumpMeasSpeedRPM      = 0.0F;
     pumpMeasRotSpeedRPM   = 0.0F;
 
+    rotorRevsPrev  = getH4RotorRevsCounter();
+    rotorRevsAccum = 0;
+
     setH4Direction( MOTOR_DIR_FORWARD );
     setH4SetSpeed( 0 );
     setH4Enabled( TRUE );
@@ -87,8 +93,10 @@
  *************************************************************************/
 void readPeristalticPumps( void )
 {
-    U16 period = getH4Period();
-    S16 rotPer = getH4RotorCount();
+    U16 delta;
+    U16 period       = getH4Period();
+    S16 rotPer       = getH4RotorCount();
+    U16 rotorRevsNow = getH4RotorRevsCounter();
 
     // update measured pump motor speed
     if ( period != H4_ZERO_SPEED_PERIOD )
@@ -130,10 +138,28 @@
     {
         pumpHomeLowSignalSeen = TRUE;
     }
+
+    // update accumulated rotor revolutions count (extend 16-bit FPGA counter to 32-bit)
+    delta = u16DiffWithWrap( rotorRevsPrev, rotorRevsNow );
+    rotorRevsAccum += (U32)delta;
+    rotorRevsPrev = rotorRevsNow;
 }
 
 /*********************************************************************//**
  * @brief
+ * The getPeristalticPumpRotorRevs function returns the accumulated
+ * rotor revolutions count for the blood pump.
+ * @details \b Inputs: rotorRevsAccum
+ * @details \b Outputs: none
+ * @return Accumulated rotor revolutions count.
+ *************************************************************************/
+U32 getPeristalticPumpRotorRevs( void )
+{
+    return rotorRevsAccum;
+}
+
+/*********************************************************************//**
+ * @brief
  * The cmdPeristalticPumpHome function initiates a pump home operation.
  * @details \b Inputs: none
  * @details \b Outputs: pumpHomeInProgress, FPGA
Index: firmware/App/Drivers/PeristalticPump.h
===================================================================
diff -u -r395522dffef1348e176564925656012f529c1910 -rfbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3
--- firmware/App/Drivers/PeristalticPump.h	(.../PeristalticPump.h)	(revision 395522dffef1348e176564925656012f529c1910)
+++ firmware/App/Drivers/PeristalticPump.h	(.../PeristalticPump.h)	(revision fbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3)
@@ -45,6 +45,7 @@
 S32  getPeristalticPumpSetSpeed( void );
 F32  getPeristalticPumpMeasSpeed( void );
 F32  getPeristalticPumpMeasRotorSpeed( void );
+U32  getPeristalticPumpRotorRevs( void );
 
 BOOL cmdPeristalticPumpHome( void );
 void cancelPeristalticPumpHome( void );
Index: firmware/App/Services/FpgaTD.c
===================================================================
diff -u -r04c811aa50770c85837d89b7e661b66f33decfb9 -rfbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3
--- firmware/App/Services/FpgaTD.c	(.../FpgaTD.c)	(revision 04c811aa50770c85837d89b7e661b66f33decfb9)
+++ firmware/App/Services/FpgaTD.c	(.../FpgaTD.c)	(revision fbe7e9a870c7ad78d3bd26f0f5cbb0277c733ac3)
@@ -152,7 +152,7 @@
     U08 h6RotorStatus;                          ///< Reg 346.  H6 rotor status.
     U08 reserved5;                              ///< Reg 347.  Reserved register.
     U16 h12Speed;                               ///< Reg 348.  H12 speed (air pump in RPM).
-    U16 rotorRevsCounter;                       ///< Reg 350.  Rotor revs counter
+    U16 h4RotorRevsCounter;                     ///< Reg 350.  Rotor revs counter
     U16 baroManufactInfo;                       ///< Reg 352.  Baro sensor manufacturing information.
     U16 baroPresSensitivity;                    ///< Reg 354.  Baro sensor prom coefficient 1.
     U16 baroPresOffset;                         ///< Reg 356.  Baro sensor prom coefficient 2.
@@ -612,7 +612,7 @@
  *************************************************************************/
 U16 getH4RotorRevsCounter( void )
 {
-    return fpgaSensorReadings.rotorRevsCounter;
+    return fpgaSensorReadings.h4RotorRevsCounter;
 }
 
 /*********************************************************************//**