Xilinx Blockset Overview

Precision

The fundamental computational mode in the Xilinx Blockset is arbitrary precision fixed point arithmetic. Most blocks give you the option of choosing the precision, i.e. the number of bits and binary point position.

By default, the output of Xilinx blocks is full precision; that is, sufficient precision to represent the result without error. Most blocks have a User-Definedprecision option that fixes the number of total and fractional bits.

Number of Bits

When you have specify user-defined precision, you will be asked to specify how many bits the output should have.

Binary Point

You will also be asked to specify how many bits are to the right of the binary point (i.e., the size of the fraction). The binary point position must be between zero and the number of bits in the number’s container.

Overflow and Quantization

When user-defined precision is selected, errors may result from overflow or quantization. Overflow occurs if a value lies outside the representable range. Quantization error occurs if the number of fractional bits is insufficient to represent the fractional portion of a value.

The Xilinx fixed point data type supports several options for user-defined precision. In the case of overflow, the options are to saturate to the largest positive (or smallest negative) value, wrap the value (i.e., discard any significant bits beyond the most- significant bit in the fixed point number), or flag an overflow as a Simulink error during simulation.

In the case of quantization, the options are to round to the nearest representable value or to the value farthest from zero if there are two equidistant nearest representable values, or to truncate the data (i.e., discard bits to the right of the least significant bit).

It is important to realize that whatever option is selected, the generated HDL model and Simulink model will behave identically.

Override with Doubles

An Override with Doubles message appears on many Xilinx Blocks, with some variations. Variations are:

Override Computation with Doubles

Override Constant with Double

Override Output with Doubles

Override Storage with Doubles

Most Simulink blocks use double precision floating point signals and arithmetic. However, when such a signal passes through Xilinx Gateway In block, it is converted to a fixed point signal. Later, when passing through a Xilinx Gateway Out block, the signals are converted back into double precision floating point.

Common Options in Block Parameters Dialog Box

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Xilinx V2.1 manual Precision, Number of Bits, Overflow and Quantization, Override with Doubles, Binary Point

V2.1 specifications

Xilinx V2.1 is a notable iteration in the series of versatile and robust Field-Programmable Gate Arrays (FPGAs) developed to cater to a wide range of applications. Launched to provide enhancements in performance and flexibility, V2.1 embodies sophisticated technologies and features that stand out in the electronics industry.

One of the primary features of Xilinx V2.1 is its improved processing power. The architecture has been optimized to support higher clock speeds and increased logic density, allowing for more complex designs to be implemented effectively. This boost in performance is facilitated by utilizing advanced silicon technologies, which significantly reduce power consumption while maximizing efficiency.

Another significant characteristic of Xilinx V2.1 is its enhanced I/O (Input/Output) capabilities. The device supports a variety of industry-standard interfaces, which include PCI Express, SATA, and various serial communication protocols. Such adaptability ensures seamless integration into existing systems, providing engineers with the flexibility to adapt to various application requirements without the need for substantial redesign efforts.

Xilinx V2.1 also features improved scalability, making it a prime choice for applications that demand diverse performance levels. This device supports an array of configurations and can be used in small-scale projects as well as in larger, more demanding environments requiring extensive resources. This scalability is further aided by support for multiple development platforms, enabling rapid prototyping and simplifying the design process.

Security is increasingly becoming a priority in digital design, and Xilinx V2.1 addresses this concern via hardware security features. It includes enhanced encryption protocols and secure boot functionalities, which help protect intellectual property and sensitive data from unauthorized access.

Additionally, the integration of advanced DSP (Digital Signal Processing) blocks allows Xilinx V2.1 to efficiently handle data-intensive tasks such as video processing and real-time signal analysis. These capabilities make it suitable for applications in telecommunications, automotive systems, and industrial automation.

Xilinx V2.1 also benefits from a rich development environment, including robust software tools that facilitate design entry, simulation, and verification. The support for industry-standard programming languages like VHDL and Verilog simplifies the development process, enabling engineers to design complex systems more efficiently.

In summary, Xilinx V2.1 stands out due to its impressive combination of high performance, flexibility, scalability, security, and comprehensive development support. These features make it a valuable asset for engineers and developers looking to innovate across various sectors, from telecommunications and automotive to industrial applications.