Converting a Netlist to an NGD File

Chapter 6: NGDBuild

The following figure shows a simplified version of the NGDBuild design flow. NGDBuild invokes other programs that are not shown in the following figure.

EDIF 2 0 0	NCF	NGC Netlist	URF	NMC	UCF
				Physical Macros
Netlist	Netlist Constraints File	(XST File)	User Rules File		User Constraints File
				Referenced in Netlist

Netlist Reader

NGDBuild

NGO

Intermediate File

NGD	BLD
Generic Database	Build Report

X10031

Figure 6-1:NGDBuild Design Flow

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)” in Appendix B.

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 Chapter 5, “Logical Design Rule Check”.

4.Writes an NGD file as output

Note: This procedure, the Netlist Launcher, and the netlist reader programs are described in more detail in Appendix B, “EDIF2NGD, and NGDBuild”.

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Development System Reference Guide

8.2i specifications

Xilinx 8.2i is a significant version of the Xilinx ISE (Integrated Software Environment) that emerged in the early 2000s, marking an important milestone in the world of FPGA (Field-Programmable Gate Array) development. This version introduced a slew of advanced features, technologies, and characteristics that made it an indispensable tool for engineers and developers in designing, simulating, and implementing digital circuits.

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Xilinx 8.2i also places a strong emphasis on simulation and verification. The version integrates with various simulation tools, allowing for thorough testing of the designs before implementation. This reduces the risk of errors and ensures that the final product meets specifications.

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In summary, Xilinx 8.2i is a robust software development tool that enhances the design process for FPGAs. Its comprehensive features, including multiple design entry options, advanced synthesis and implementation tools, extensive device support, and strong simulation capabilities, make it a valuable resource for engineers and developers striving for innovation in digital design.

Xilinx 8.2i manual Converting a Netlist to an NGD File, 1NGDBuild Design Flow

Models: 8.2i

Chapter 6: NGDBuild

NMC

UCF

Figure 6-1:NGDBuild Design Flow

Converting a Netlist to an NGD File

Development System Reference Guide

8.2i specifications