Abstract:With the development of integrated and modularized civil aircraft electronic system, IMA (Integrated Modular Avionics) system comes out. It manages and deploys many individual UAs (User Applications). CDS (Cockpit Display System) which is in the civil avionics system focusing on IMA, provides the display function for UA. At the same time, CDS manages the IDUs (Integrated Display Unit) which provides the HMI for cockpit giving the feedback to UA. Developing the UA code and ARINC 661 protocol DF (Definition File) which is loaded on IDU are the responsibility of UA developers. But they are not implemented in one target PC. So, they are individual and related. In order to according with DO-178C and CAAC's certification, we do the research of development and verification of DF.