To perform back-annotation from the UNIX or DOS command line, enter the following.
ngdanno [options] ncd_file[.ncd] [ngm_file[.ngm]]
Ncd_file is the input NCD (physical design file). If you specify an NCD file on the command line without specifying an NGM file, an NGA file is generated from the NCD only. The NGA file contains annotated information about the physical implementation, but there is no logical view of the design. If you specify both an NCD and an NGM file, the resulting NGA file contains both logical and physical information for the annotated design
Ngm_file is an optional NGM file - a mapped design file containing information about the physical design and information about how the physical design corresponds to the logical design. You must specify the NGM file for NGDAnno to use the file as input. In general, the NGM file should be used, especially with HDL synthesis-based designs. In the HDL design flow, the NGM file can help to regroup logic based on the original design hierarchy.
If you do not specify an NGA file with the -o option (described in the “NGDAnno Options” section), an NGA file is generated in the same directory as the NCD. The NGA file has the same root name as the NCD file.
