Vertical Retrace Mgr
GetVBLQHdr Get the address of the VBL queue header VInstall Install vertical retrace interrupt task VRemove Remove vertical retrace interrupt task AttachVBL Make specified slot the primary video slot DoVBLTask Execute VBL tasks in the queue for a specified slot SlotVInstall Install vertical retrace interrupt task for a slot SlotVRemove Remove vertical retrace interrupt task for a slot