Article ID: 000087020 Content Type: Troubleshooting Last Reviewed: 07/04/2014

Mismatches Between Some Serial CORDIC MATLAB and RTL Models I

Environment

BUILT IN - ARTICLE INTRO SECOND COMPONENT

Critical Issue

Description

For the serial CORDIC architecture with Phase Accumulator Precision and Angular Resolution both set to values less than or equal to 10, there can be mismatches between the outputs of the MATLAB model and the RTL. These mismatches are due to rounding differences.

The affected configurations are the Serial CORDIC architecture of the NCO MegaCore function with Phase Accumulator Precision and Angular Resolution both set to values less than or equal to 10.

The design impact is a comparison of the output values from the MATLAB model and RTL design during testing may show mismatches. However, the error margin is only /-1.

Resolution

Set Phase Accumulator Precision and Angular Resolution to values greater than 10, or use a different architecture.

This issue is fixed in the NCO MegaCore function v14.0.