dio_set_step_motor(_c)

	status.i4.v = dio_set_step_motor(device_index.i4.r, set_value.r4.r
					 [,data_event.i1a.r] [,options.u4.r])

	status.i4.v = dio_set_step_motor_c(device_index.i4.v, set_value.r8.v
					   [,data_event.i1a.r] [,options.u4.v])

	This routine will set a stepping motor using supplied
	engineering-unit (e.g. mils) values.  (Note: If you simply want
	to move a motor by a number of steps, use the
	dio_set_step_motor_steps_c routine with the number of steps
	as the data.)

	device_index	motor device index
	set_value	setting value in engineering units
	[data_event]	data event for reading present position
			(default is NULL (one shot))
	[options]	setting options (not used) (default is 0)

	This function returns ACNET status values as follows:

	OK			success
	DIO_INVDBDAT		invalid device length in database
	DIO_SCALEFAIL		device scaling failed
	CLIB_INVARG		invalid data event string
	CLIB_NOTYET		data event value not supported
	negative value		ACNET format error

	This function requires the following include files:

	diolib_h, acnet_errors_h

	Related functions:

	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;
	unsigned int	options = 0;
	double	set_value = 100.0;

	status = dio_set_step_motor_c(device_index,set_value,data_event,
				      options);