Correct the acceleration

motorApp/AMCISrc/ANF2Driver.cpp

@@ -582,6 +582,30 @@ asynStatus ANF2Axis::sendAccelAndVelocity(double acceleration, double velocity)
   return asynSuccess;
 }
 
+/*
+ * This driver only sets the base speed at initialization when the configuration is sent.
+ * It is possible that the base speed (VBAS) in the motor record is inconsistent with the 
+ * base speed set at initialization, since there is no way for an asyn motor driver to force
+ * the base speed to be reset when a user changes it. The resulting acceleration calculated 
+ * by the motor record is likely to be incorrect.  The following method calculates the 
+ * acceleration that will give the correct acceleration time (ACCL) for the base speed that
+ * was specified at initialization.
+ */
+double ANF2Axis::correctAccel(double minVelocity, double maxVelocity, double acceleration)
+{
+  double accelTime;
+  double newAccel;
+  
+  accelTime = (maxVelocity - minVelocity) / acceleration;
+  newAccel = (maxVelocity - (double)baseSpeed_) / accelTime;
+
+  printf("old acceleration = %lf\n", acceleration);
+  printf("new acceleration = %lf\n", newAccel);
+  
+  return newAccel;
+}
+
+
 // MOVE
 asynStatus ANF2Axis::move(double position, int relative, double minVelocity, double maxVelocity, double acceleration)
 {
@@ -598,6 +622,9 @@ asynStatus ANF2Axis::move(double position, int relative, double minVelocity, dou
   // Clear the motition registers
   zeroRegisters(motionReg_);
 
+  // Correct the acceleration
+  acceleration = correctAccel(minVelocity, maxVelocity, acceleration);
+
   // This sets indices 2 & 3 of motionReg_
   status = sendAccelAndVelocity(acceleration, maxVelocity);
   
@@ -648,6 +675,9 @@ asynStatus ANF2Axis::home(double minVelocity, double maxVelocity, double acceler
   // Clear the motition registers
   zeroRegisters(motionReg_);
 
+  // Correct the acceleration
+  acceleration = correctAccel(minVelocity, maxVelocity, acceleration);
+
   // This sets indices 2 & 3 of motionReg_
   status = sendAccelAndVelocity(acceleration, maxVelocity);
 

motorApp/AMCISrc/ANF2Driver.h

@@ -79,6 +79,7 @@ private:
   ANF2Controller *pC_;          /**< Pointer to the asynMotorController to which this axis belongs.
                                    *   Abbreviated because it is used very frequently */
   asynStatus sendAccelAndVelocity(double accel, double velocity);
+  double correctAccel(double minVelocity, double maxVelocity, double acceleration);
   void getInfo();
   void reconfig(epicsInt32 value);
   void zeroRegisters(epicsInt32 *reg);