Index: firmware/App/Controllers/BloodFlow.c
===================================================================
diff -u -r5e77f78c5dee9dfb441bd5d2053f7f4ac50dc619 -r29e57b5232f605a871c62580e16a7db297aae992
--- firmware/App/Controllers/BloodFlow.c	(.../BloodFlow.c)	(revision 5e77f78c5dee9dfb441bd5d2053f7f4ac50dc619)
+++ firmware/App/Controllers/BloodFlow.c	(.../BloodFlow.c)	(revision 29e57b5232f605a871c62580e16a7db297aae992)
@@ -55,8 +55,10 @@
 
 #define BP_HOME_RATE                        100             ///< target pump speed (in estimate mL/min) for homing.
 #define BP_HOME_TIMEOUT_MS                  10000           ///< maximum time allowed for homing to complete (in ms).
-#define BP_SPEED_CALC_INTERVAL              ( 40 / TASK_PRIORITY_INTERVAL )  ///< interval (ms/task time) at which the blood pump speed is calculated.
-#define BP_SPEED_CALC_BUFFER__LEN           25              ///< number of hall sensor counts kept in buffer to hold last 1 second of count data.
+/// interval (ms/task time) at which the blood pump speed is calculated (every 40 ms).
+#define BP_SPEED_CALC_INTERVAL              ( 40 / TASK_PRIORITY_INTERVAL )
+/// number of hall sensor counts kept in buffer to hold last 1 second of count data.
+#define BP_SPEED_CALC_BUFFER__LEN           ( 1000 / BP_SPEED_CALC_INTERVAL / TASK_PRIORITY_INTERVAL )
 #define BP_HALL_EDGE_COUNTS_PER_REV         48              ///< number of hall sensor edge counts per motor revolution.
 #define BP_MAX_ROTOR_SPEED_RPM              100.0           ///< maximum rotor speed allowed for blood pump.
 
@@ -905,7 +907,9 @@
     {
         U16 bpMotorHallSensorCount = getFPGABloodPumpHallSensorCount();
         U32 nextIdx = INC_WRAP( bpMotorSpeedCalcIdx, 0, BP_SPEED_CALC_BUFFER__LEN - 1 );
-        U16 incDelta = ( bpMotorHallSensorCount >= bpLastMotorHallSensorCounts[ nextIdx ] ? bpMotorHallSensorCount - bpLastMotorHallSensorCounts[ nextIdx ] : ( HEX_64_K - bpLastMotorHallSensorCounts[ nextIdx ] ) + bpMotorHallSensorCount );
+        U16 incDelta = ( bpMotorHallSensorCount >= bpLastMotorHallSensorCounts[ bpMotorSpeedCalcIdx ] ? \
+                         bpMotorHallSensorCount - bpLastMotorHallSensorCounts[ bpMotorSpeedCalcIdx ] : \
+                         ( HEX_64_K - bpLastMotorHallSensorCounts[ bpMotorSpeedCalcIdx ] ) + bpMotorHallSensorCount );
         U16 decDelta = HEX_64_K - incDelta;
         U16 delta;