Nios II CRC Acceleration Design Example

Overview

The cyclic redundancy check (CRC) algorithm detects the corruption of data during transmission, and detects a higher percentage of errors than a simple checksum. The CRC calculation consists of an iterative algorithm involving XORs and shifts that execute much faster in hardware than in software. This design uses the CRC-32 standard. It is implemented as a custom component alongside a Nios^® II embedded processor. The design achieves over 5 Gbps throughput, demonstrating the levels of performance improvement that can be achieved by performing the function in hardware.

Features

• Supports any CRC algorithm between 1–128 bits
• CRC component throughput of 32 Mbps per MHz
• 8-, 16-, 24-, and 32-bit datapaths
• Up to 2000x speed improvement over a software-only implementation
• Low latency performance of 0 cycle write latency and 1 cycle read latency
• Two example designs targeting Stratix^® II and Cyclone^® II FPGAs

Demonstrated Altera Technology

• Stratix II FPGAs
• RoHS-compliant Nios II Development Kit, Stratix II Edition
• Cyclone II FPGAs
• Nios II Development Kit, Cyclone II Edition
• Nios II Embedded Processor

Block Diagram

Figure 1 shows the Avalon^® CRC component block diagram.

Figure 1. Avalon CRC Component Block Diagram

Note:

1. Data path = crc_width.

Using This Design Example

Download the CRC Example Design (.zip file)

The use of this design is governed by, and subject to, the terms and conditions of the Altera Hardware Reference Design License Agreement.

The .zip file contains all the necessary hardware and software files to reproduce the example, as well as a readme.txt file. The readme.txt file contains instructions for re-building the design.

Design Examples Disclaimer

These design examples may only be used within Altera Corporation devices and remain the property of Altera. They are being provided on an “as-is” basis and as an accommodation; therefore, all warranties, representations, or guarantees of any kind (whether express, implied, or statutory) including, without limitation, warranties of merchantability, non-infringement, or fitness for a particular purpose, are specifically disclaimed. Altera expressly does not recommend, suggest, or require that these examples be used in combination with any other product not provided by Altera.