FIR II IP Core: User Guide

ID 683208
Date 6/12/2020
Public

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4.5. FIR II IP Core Multiple Coefficient Banks

The FIR II IP core supports multiple coefficient banks.

The FIR filter can switch between different coefficient banks dynamically, which enables the filter to switch between infinite number of coefficient sets. Therefore, while the filter uses one coefficient set, you can update other coefficient sets.You can also set different coefficient banks for different channels and use the channel signal to switch between coefficient sets.

The IP core uses multiple coefficient banks when you load multiple sets of coefficients from a file.

RT**Refer to “Loading Coefficients from a File” on page 3–3.

Based on the number of coefficient banks you specify, the IP core extends the width of the ast_sink_data signal to support two additional signals— bank signal (bankIn) and input data (xIn) signal. The most significant bits represent the bank signals and the least significant bits represent the input data.

You can switch the coefficient bank from 0 to 3 using the bankIn signal when the filter runs.

Figure 33. Timing Diagram of a Single-Channel Filter with 4 Coefficient Banks
Figure 34. Timing Diagram of a Four-Channel Filter with 4 Coefficient BanksEach channel has a separate corresponding coefficient set. The IP core drives the bank inputs for different channels with their channel number respectively throughout the filter operation.