R

EPROM

An EPROM is an erasable PROM, which can be reprogrammed many times. Previous programs are simply erased by exposing the chip to ultra-violet light.

An EEPROM, or electrically erasable PROM, is another variety of

EPROM that can be erased electrically.

F

FD

FD is a D flip-flop used in CLBs. Contrast with IFD.

FDSD

FDSD is a D flip-flop with Set Direct.

FIFO

A FIFO is a serial-in/serial-out shift register.

fitting

Fitting is the process of putting logic from your design into physical macrocell locations in the CPLD. Routing is performed automatically, and because of the UIM architecture, all designs are routable.

fitter

The fitter is the software that maps a PLD logic description into the target CPLD.

flat design

A flat design is a design composed of multiple sheets at the top-level schematic.

flattening

Flattening is the process of resolving all of the hierarchy references in a design. If a design contains several instantiations of a logic module, the flattened version of that design will duplicate the logic for each instantiation. A flattened design still contains hierarchical names for instances and nets.

flip-flop

A flip-flop is a simple two-state logic buffer activated by a clock and fed by a single input working in combination with the clock. The states are High and Low. When the clock goes High, the flip-flop works as a buffer as it outputs the value of the D input at the time the clock rises.

The value is kept until the next clock cycle (rising clock edge). The output is not affected when the clock goes Low (falling clock edge).

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Development System Reference Guide

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Xilinx 8.2i manual Eprom, Fdsd, Fifo

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.