User guide

112 www.xilinx.com System Generator for DSP User Guide
UG640 (v 12.2) July 23, 2010
Chapter 1: Hardware Design Using System Generator
Generate and Assign Coefficients for the FIR Filter
1. Drag and drop the FDATool block into your model from the DSP Xilinx Blockset
Library.
2. Double-click on the FDATool block and enter the following specifications in the Filter
Design & Analysis Tool for a low-pass filter designed to eliminate high-frequency
noise in audio systems:
♦ Response Type: Lowpass
♦ Filter Order: Minimum order
♦ Frequency Specifications
- Units: Hz
- Fs: 44100
- Fpass: 6000
- Fstop: 7725
♦ Magnitude Specifications
- Units: dB
- Apass: 1
- Astop: 48
3. Click on Design Filter at the bottom of the tool window to find out the filter order and
observe the magnitude response.
You can also view the phase response, impulse response, coefficients and more by
selecting the appropriate icon at the top-right of the GUI. Based on the FDATool, a 43-
tap FIR filter (order 0-42) is required in order to meet the design specifications listed
above.