dio_calculate_step_motor_steps_c

	status.i4.v = dio_calculate_step_motor_steps_c(device_index.i4.v,
						       desired_value.r8.v,
						       current_value.r8.v,
						       num_steps.i4.r
						       [,options.u4.v]
						       [,data_event.i1a.r])

	This routine calculates the number of steps needed to move
	a stepping motor to a desired position.

	device_index	motor device index
	desired_value	desired value in engineering units
	current_value	current value in engineering units
	num_steps	returned number of steps
	[options]	calculation options
			(DIO_STEP_OPT_NONE -> no options selected (default),
			 DIO_STEP_OPT_READ_CURRENT_VALUE -> read the current
							    value)
	[data_event]	data event for reading present position
			(default is NULL (one shot))

	This function returns ACNET status values as follows:

	OK			success
	DIO_INVDBDAT		invalid device length in database
	DIO_SCALEFAIL		device scaling failed
	negative value		other ACNET format error

	This function requires the following include files:

	diolib_h, acnet_errors_h

	Related functions:

	dio_set_step_motor(_c), dio_set_step_motor_steps_c, dio_is_step_motor,
	dio_move_step_motor

	C/C++ usage:

	char	*data_event = (char *) NULL;
	int	status;
	int	device_index = 5122;
	int	num_steps;
	unsigned int	options = DIO_STEP_OPT_NONE;
	double	desired_value = 100.0;
	double	current_value = 90.0;

	status = dio_calculate_step_motor_steps_c(device_index,desired_value,
						  current_value,&num_steps,
						  options,data_event);