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CPLD Implementation
file. The output NGD file can then be mapped to the targeted device
family.
The following file types are input files for the translate process:
•
Design file EDIF netlists (EDN files)
•
User Constraints File (UCF File)
The User Constraints File (default name is project_name.ucf) is an
ASCII file that you create with a text editor or using the Xilinx
Constraints Editor. The file contains timing and layout
constraints that affect how the logical design is implemented in
the target device. The constraints in the file are added to the
information in the output NGD file.
•
Netlist Constraints File (NCF file)
The Netlist Constraints File (top_source_name.ncf) contains
constraints specified within the Engineering Capture System
(ECS) and synthesis tool. The netlist reader invoked by the
Translate process adds the constraints to an intermediate NGO
file and the output NGD file.
•
Module definition files (NGC files)
NGC files are binary files containing the implementation of a
module in the design. Some compilers like XST create an NGC
file to represent a design module together with its constraints.
The following file types are output files for the translate process:
•
Xilinx Native Generic Database (NGD file)
The NGD file (top_source_name.ngd) is a binary file containing a
logical description of the design expressed both in terms of the
hierarchy used when the design was first created and in terms of
lower-level Xilinx primitives to which the hierarchy resolves. The
file also contains all of the constraints applied to the design
during design entry or entered in a UCF (User Constraints File).
•
Translation Report (BLD file)
The Translation Report (top_source_name.bld file) contains
information about the Translate (NGDBuild) run and its
subprocesses. See the “Viewing Implementation Reports” section
of the “Implementation” chapter and the “Translation Report”
section below for more information.
ISE 4 User Guide
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