Over the last decade a new data interface for CAM/CNC integration has been established to replace ISO 6983. The new standard, ISO 14649 (STEP-NC), provides a comprehensive data model that describes both geometrical and technological information in an object-oriented way. In order to bridge the gap between such rich-information programs and the legacy CNC systems, this paper presents a framework for manipulating the manufacturing data in STEP-NC part programs. The proposed system provides a basic platform for STEP-NC program interpretation, geometry visualization, micro-process planning and program re-generation. Major issues relating to the realization of manufacturing information extraction and shop-floor-level process planning are addressed in particular, and a prototype for STEP-NC turning process is implemented to demonstrate the feasibility of the approach.