Index: firmware/App/Controllers/BloodFlow.c
===================================================================
diff -u -r9a9d04b84f4345fca87fb14d26f09d497b08aae8 -ra74a984a7059f75d86ad87d6d9499bd8f94cc976
--- firmware/App/Controllers/BloodFlow.c	(.../BloodFlow.c)	(revision 9a9d04b84f4345fca87fb14d26f09d497b08aae8)
+++ firmware/App/Controllers/BloodFlow.c	(.../BloodFlow.c)	(revision a74a984a7059f75d86ad87d6d9499bd8f94cc976)
@@ -46,8 +46,6 @@
 #define BP_CONTROL_INTERVAL                 ( 1000 / TASK_GENERAL_INTERVAL ) // interval (ms/task time) at which the blood pump is controlled
 #define BP_P_COEFFICIENT                    0.00005         // P term for blood pump control
 #define BP_I_COEFFICIENT                    0.00015         // I term for blood pump control
-#define BP_MAX_PWM_DC_DELTA                 0.01            // prevents large steps in PWM duty cycle while controlling
-#define BP_MIN_PWM_DC_DELTA                -0.01
 
 #define BP_MAX_CURR_WHEN_STOPPED_MA         150.0           // motor controller current should not exceed this when pump should be stopped
 #define BP_MIN_CURR_WHEN_RUNNING_MA         150.0           // motor controller current should always exceed this when pump should be running
@@ -100,13 +98,15 @@
 
 // ********** private data **********
 
-static BLOOD_PUMP_STATE_T bloodPumpState = BLOOD_PUMP_OFF_STATE;                // current state of blood flow controller state machine
-static U32 bloodFlowDataPublicationTimerCounter = 0;                            // used to schedule blood flow data publication to CAN bus
-static BOOL isBloodPumpOn = FALSE;                                              // blood pump is currently running
-static F32 bloodPumpPWMDutyCyclePct = 0.0;                                      // initial blood pump PWM duty cycle
-static F32 bloodPumpPWMDutyCyclePctSet = 0.0;                                   // currently set blood pump PWM duty cycle
-static MOTOR_DIR_T bloodPumpDirection = MOTOR_DIR_FORWARD;                      // requested blood flow direction
-static MOTOR_DIR_T bloodPumpDirectionSet = MOTOR_DIR_FORWARD;                   // currently set blood flow direction
+static BLOOD_PUMP_STATE_T bloodPumpState = BLOOD_PUMP_OFF_STATE;                    // current state of blood flow controller state machine
+static U32 bloodFlowDataPublicationTimerCounter = 0;                                // used to schedule blood flow data publication to CAN bus
+static BOOL isBloodPumpOn = FALSE;                                                  // blood pump is currently running
+static F32 bloodPumpPWMDutyCyclePct = 0.0;                                          // initial blood pump PWM duty cycle
+static F32 bloodPumpPWMDutyCyclePctSet = 0.0;                                       // currently set blood pump PWM duty cycle
+static MOTOR_DIR_T bloodPumpDirection = MOTOR_DIR_FORWARD;                          // requested blood flow direction
+static MOTOR_DIR_T bloodPumpDirectionSet = MOTOR_DIR_FORWARD;                       // currently set blood flow direction
+static PUMP_CONTROL_MODE_T bloodPumpControlMode = PUMP_CONTROL_MODE_CLOSED_LOOP;    ///< requested blood pump control mode.
+static PUMP_CONTROL_MODE_T bloodPumpControlModeSet = PUMP_CONTROL_MODE_CLOSED_LOOP; ///< currently set blood pump control mode.
 
 DATA_DECL( U32, BloodFlowDataPub, bloodFlowDataPublishInterval, BLOOD_FLOW_DATA_PUB_INTERVAL, BLOOD_FLOW_DATA_PUB_INTERVAL ); // interval (in ms) at which to publish blood flow data to CAN bus
 DATA_DECL( S32, TargetBloodFlowRate, targetBloodFlowRate, 0, 0 );               // requested blood flow rate
@@ -178,9 +178,10 @@
  * Outputs : targetBloodFlowRate, bloodPumpdirection, bloodPumpPWMDutyCyclePct
  * @param flowRate : new target blood flow rate
  * @param dir : new blood flow direction
+ * @param mode : new control mode
  * @return TRUE if new flow rate & dir are set, FALSE if not
  *************************************************************************/
-BOOL setBloodPumpTargetFlowRate(  U32 flowRate, MOTOR_DIR_T dir  )
+BOOL setBloodPumpTargetFlowRate( U32 flowRate, MOTOR_DIR_T dir, PUMP_CONTROL_MODE_T mode )
 {
     BOOL result = FALSE;
 
@@ -193,6 +194,7 @@
             resetBloodFlowMovingAverage();
             targetBloodFlowRate.data = ( dir == MOTOR_DIR_FORWARD ? (S32)flowRate : (S32)flowRate * -1 );
             bloodPumpDirection = dir;
+            bloodPumpControlMode = mode;
             // set PWM duty cycle target to an estimated initial target to ramp to based on target flow rate - then we'll control to flow when ramp completed
             bloodPumpPWMDutyCyclePct = BP_PWM_FROM_ML_PER_MIN((F32)flowRate);   // ~ 8% per 100 mL/min with a 10% zero offset added in (e.g. 100 mL/min = 8+10 = 18%)
 
@@ -377,6 +379,13 @@
     {
         resetBloodFlowMovingAverage();
         resetPIController( PI_CONTROLLER_ID_BLOOD_FLOW, bloodPumpPWMDutyCyclePctSet );
+        bloodPumpControlModeSet = bloodPumpControlMode;
+        // if open loop mode, set PWM to requested duty cycle where it will stay during control state
+        if ( bloodPumpControlModeSet == PUMP_CONTROL_MODE_OPEN_LOOP )
+        {
+            bloodPumpPWMDutyCyclePctSet = bloodPumpPWMDutyCyclePct;
+            setBloodPumpControlSignalPWM( bloodPumpPWMDutyCyclePct );
+        }
         result = BLOOD_PUMP_CONTROL_TO_TARGET_STATE;
     }
     // continue ramp up
@@ -414,6 +423,13 @@
     {
         resetBloodFlowMovingAverage();
         resetPIController( PI_CONTROLLER_ID_BLOOD_FLOW, bloodPumpPWMDutyCyclePctSet );
+        bloodPumpControlModeSet = bloodPumpControlMode;
+        // if open loop mode, set PWM to requested duty cycle where it will stay during control state
+        if ( bloodPumpControlModeSet == PUMP_CONTROL_MODE_OPEN_LOOP )
+        {
+            bloodPumpPWMDutyCyclePctSet = bloodPumpPWMDutyCyclePct;
+            setBloodPumpControlSignalPWM( bloodPumpPWMDutyCyclePct );
+        }
         result = BLOOD_PUMP_CONTROL_TO_TARGET_STATE;
     }
     // continue ramp down
@@ -439,16 +455,20 @@
 static BLOOD_PUMP_STATE_T handleBloodPumpControlToTargetState( void )
 {
     BLOOD_PUMP_STATE_T result = BLOOD_PUMP_CONTROL_TO_TARGET_STATE;
-    F32 tgtFlow = (F32)getTargetBloodFlowRate();
-    F32 actFlow = getMeasuredBloodFlowRate();
-    F32 newPWM;
 
     // control at set interval
     if ( ++bpControlTimerCounter >= BP_CONTROL_INTERVAL )
     {
-        newPWM = runPIController( PI_CONTROLLER_ID_BLOOD_FLOW, tgtFlow, actFlow );
-        bloodPumpPWMDutyCyclePctSet = newPWM;
-        setBloodPumpControlSignalPWM( newPWM );
+        if ( bloodPumpControlModeSet == PUMP_CONTROL_MODE_CLOSED_LOOP )
+        {
+            F32 tgtFlow = (F32)getTargetBloodFlowRate();
+            F32 actFlow = getMeasuredBloodFlowRate();
+            F32 newPWM;
+
+            newPWM = runPIController( PI_CONTROLLER_ID_BLOOD_FLOW, tgtFlow, actFlow );
+            bloodPumpPWMDutyCyclePctSet = newPWM;
+            setBloodPumpControlSignalPWM( newPWM );
+        }
         bpControlTimerCounter = 0;
     }