HDL Entry and Synthesis, Functional Simulation

Design Entry and Synthesis

HDL Entry and Synthesis

A typical Hardware Description Language (HDL) supports a mixed-level description in which gate and netlist constructs are used with functional descriptions. This mixed-level capability enables you to describe system architectures at a high level of abstraction, then incrementally refine the detailed gate-level implementation of a design.

HDL descriptions offer the following advantages:

•You can verify design functionality early in the design process. A design written as an HDL description can be simulated immediately. Design simulation at this high level, at the gate-level before implementation, allows you to evaluate architectural and design decisions.

•An HDL description is more easily read and understood than a netlist or schematic description. HDL descriptions provide technology-independent documentation of a design and its functionality. Because the initial HDL design description is technology independent, you can use it again to generate the design in a different technology, without having to translate it from the original technology.

•Large designs are easier to handle with HDL tools than schematic tools.

After you create your HDL design, you must synthesize it. During synthesis, behavioral information in the HDL file is translated into a structural netlist, and the design is optimized for a Xilinx device. Xilinx supports HDL synthesis tools for several third-party synthesis vendors. In addition, Xilinx offers its own synthesis tool, Xilinx Synthesis Technology (XST). See the Xilinx Synthesis Technology (XST) User Guide for information. For detailed information on synthesis, see the Synthesis and Simulation Design Guide.

Functional Simulation

After you create your design, you can simulate it. Functional simulation tests the logic in your design to determine if it works properly. You can save time during subsequent design steps if you perform functional simulation early in the design flow. See “Simulation” for more information.

Constraints

You may want to constrain your design within certain timing or placement parameters. You can specify mapping, block placement, and timing specifications.

You can enter constraints manually or use the Constraints Editor, Floorplanner, or FPGA Editor, which are graphical user interface (GUI) tools provided by Xilinx. You can use the Timing Analyzer GUI or TRACE command line program to evaluate the circuit against these constraints by generating a static timing analysis of your design. See Chapter 12, “TRACE” and the online Help provided with each GUI for information. See the Constraints Guide for detailed information on constraints.

Mapping Constraints (FPGAs Only)

You can specify how a block of logic is mapped into CLBs using an FMAP for all Spartan FPGA and Virtex FPGA families. These mapping symbols can be used in your schematic. However, if you overuse these specifications, it may be difficult to route your design.

Development System Reference Guide

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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.

One of the standout features of Xilinx 8.2i is its enhanced design entry capabilities. This version supports multiple design entry methods, including schematic entry, VHDL, and Verilog HDL, giving engineers the flexibility to choose their preferred approach. The integrated environment provides user-friendly graphical interfaces, making it accessible for both novice and experienced users.

Xilinx 8.2i's synthesis tools have been improved to enable more efficient design compilation and optimization. The new algorithms used in this version facilitate faster synthesis times while reducing power consumption and improving performance. Furthermore, it features support for advanced FPGA architectures, which allows for the implementation of more complex designs with greater efficiency.

The implementation tools in Xilinx 8.2i include advanced place and route capabilities, utilizing state-of-the-art algorithms for optimized resource usage. These tools enable designers to make better use of FPGA resources, ensuring that designs fit within the constraints of the target device while maximizing performance.

Another key characteristic of Xilinx 8.2i is its extensive support for various Xilinx devices such as the Spartan, Virtex, and CoolRunner series. This compatibility ensures that developers can leverage the powerful features of these FPGA families, including high-speed transceivers and DSP slices.

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.

In addition, this version includes support for design constraints, enabling engineers to specify timing, area, and other critical design parameters. By accommodating constraints, Xilinx 8.2i helps in achieving reliable and efficient designs tailored to project needs.

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 HDL Entry and Synthesis, Functional Simulation, Constraints

Models: 8.2i