AR# 21414

LogiCORE Distributed Arithmetic FIR (DA FIR) - Why is there a mismatch between the behavioral simulation width and the instantiation template for Interpolating Halfband filters?

Description

Keywords: COREGen, CORE Generator, DSP

Why is there a mismatch between the behavioral simulation width and the instantiation template for Interpolating Halfband filters?

For example, when I generate the DA FIR with interpolating halfband, selected the behavioral simulation model, I can see that the generic map in the wrapper file contains this line:
c_result_width => 18

It should be:
c_result_width => 19

This can be seen when you look at the instantiation template, which will have the following:
result_width std_logic_vector(18 downto 0)

Solution

To work around this issue, modify the following line in the wrapper file:
c_result_width => 18

Just add "1" to the width and this will resolve the problem.

For example:
c_result_width => 19
AR# 21414
Date 04/01/2009
Status Archive
Type General Article