Example Code

Overview

This example generates a 16-bit error checking code that will efficiently confirm the correct retrieval of information.

Description

This code completes the complex calculation of taking the quotient of the input message and a known X value and passing that value as a Cyclic Redundancy Check (CRC). The message as well as the CRC are sent to their destination where the receiver will perform the same division this time with the message and the CRC. If there are no errors in the message, then the destination should get the X value as the quotient. In both of these calculations, any remainder generated is discarded.

The CRC- 16 bits code computes a 16-bit cyclical redundancy check (CRC) algorithm on an input serial data stream. The polynomial can be defined to implement CRC functions, such as the CRC-16 or CCITT algorithm. A seed value can be specified to initialize the starting data value.
For CRC_CCITT: Polynomial Register = X16+ X12 + X5 +1 (0x1021)
Seed Register: 0xFFFF

Requirements

LabVIEW 2012 (or compatible)

Steps to Implement or Execute Code

1. Open the VI "Cyclic Redundancy Check (16 bits)_LV2012_NI Verified"

2. Enter the message to be coded in the String
3. Run the VI
4. Check the code in CRC-CCITT correspondent to your message

Additional Information or References

CRC-16 General Circuit. (Reference: http://www.cypress.com/file/127146/download)

 Block Diagram

**This document has been updated to meet the current required format for the NI Code Exchange.**