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AR# 62428

FIR compiler v7.1 - SysGen FIR compiler GUI unclear on fractional rate decimation filters


When specifying the sample period for fractional rate filters, the parameter changes dynamically depending on whether it is a decimation filter or interpolation filter.

For decimators, the output sample rate is specified, but for interpolators, the input sample rate should be used.

In Vivado, the IP Catalog GUI changes dynamically (based on the resampling rate) to make this clear when specifying the sample period.

Sysgen does not change dynamically so it is more difficult to set the sample period.

Can the GUI be changed to update dynamically, similar to the Vivado IP catalog?

This would make it clearer how this parameter should be set.

Also, the GUI does not allow me to set the 'maximum possible' oversampling period option.

Why is this the case?


This issue has been fixed in the Vivado 2014.3 Release.

The GUI has been updated to support the explicit selection of Input OR Output Sample period specification methods for filter structures. 

Also the core has been updated to support the "Maximum Possible" oversampling specification for fractional rates filters. 

However, if the input or output rate resolves to be fractional, the interface control ports will be enabled.

AR# 62428
Date Created 10/09/2014
Last Updated 12/18/2014
Status Active
Type General Article
  • FIR Compiler