R

library

A library is a set of macros, such as adders, buffers, and flip-flops that is part of the Xilinx interface. A library is used to create schematic designs.

load

A load is an input port.

logic

Logic is one of the three major classes of ICs in most digital electronic systems: microprocessors, memory, and logic. Logic is used for data manipulation and control functions that require higher speed than a microprocessor can provide.

logical annotation

The method of back-annotation that uses the old .ngm and .ncd to attempt to back-annotate the physical information (physical delays) back into the logical (.ngd) file.

logic allocation file

A logic allocation file, design.ll file, designates a file used for probing. The file provides bit locations of the values of RAM, I/O, latches, and flip-flops.

logic optimization

Logic optimization is the process that decreases the area or increases the speed of a design.

longline

A longline connects to a primary global net or to any secondary global net. Each CLB has four dedicated vertical longlines. These lines are very fast.

look-up table (LUT)

A Look-Up Table (LUT), implements Boolean functions.

See function generator.

low

Low is a logical state for which no output is generated.

LSB

An LSB, or least significant bit, is the left-most bit of the bus bounds or indexes. In one-hot and twos-complement encoding, the LSB is the right-most bit.

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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.
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