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Chapter 6: NGDBuild
Converting a Netlist to an NGD File
NGDBuild performs the following steps to convert a netlist to an NGD file:
1.
Reads the source netlist
NGDBuild invokes the Netlist Launcher. The Netlist Launcher determines the input netlist type and starts
the appropriate netlist reader program. The netlist reader incorporates NCF files associated with each netlist.
NCF files contain timing and layout constraints for each module. The Netlist Launcher is described in
detail in the Netlist Launcher (Netlister) appendix.
2.
Reduces all components in the design to NGD primitives
NGDBuild merges components that reference other files. NGDBuild also finds the appropriate system
library components, physical macros (NMC files), and behavioral models.
3.
Checks the design by running a Logical Design Rule Check (DRC) on the converted design
Logical DRC is a series of tests on a logical design. It is described in the Logical Design Rule Check chapter.
4.
Writes an NGD file as output
Note This procedure, the Netlist Launcher, and the netlist reader programs are described in more detail in the
Appendix.
NGDBuild Input Files
NGDBuild uses the following files as input:
The input design can be an EDIF 2 0 0 or NGC netlist file. If the input netlist is in another format recognized by
the Netlist Launcher, the Netlist Launcher invokes the program necessary to convert the netlist to EDIF format
and then invokes the appropriate netlist reader, EDIF2NGD.
With the default Netlist Launcher options, NGDBuild recognizes and processes files with the extensions shown
in the following table. NGDBuild searches the top-level design netlist directory for a netlist file with one of the
extensions. By default, NGDBuild searches for an EDIF file first.
File Type
Recognized Extensions
EDIF
.sedif, .edn, .edf, .edif
NGC
.ngc
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Command Line Tools User Guide
UG628 (v 11.4) December 2, 2009