Altera DSP Development Kit, Cyclone II Edition Getting Started - Manual (Page 30)

2–20 Getting Started User Guide Altera Corporation
DSP Development Kit, Cyclone II Edition August 2006
Testing the Board Using the Factory Design
Collecting Data Using the SignalTap II Logic Analyzer
To collect data from the design for analysis, follow these steps.
1. In the Instance Manager section of the SignalTap II window, click
Run Analysis
and observe the following:
a. Observe the D/A converter input on comb[13..0]. It shows a
combination of two sine waves.
b. Observe the A/D converter output on a2db[11..0]. It shows
an attenuated combination of two sine waves.
1
The A/D converter output is attenuated because the bit
resolution is reduced from 14 bits to 12 bits. Analog
circuitry on the Cyclone II DSP development board also
causes some additional attenuation.
2. Choose Create SignalTap II List File from Create / Update (File
Menu). The Quartus II software generates the file
sines_auto_signaltap_0.txt
in the project directory.
Analyzing the Data in the MATLAB Software
To analyze the a2db data from sines_auto_signaltap_0.txt in MATLAB,
follow these steps:
1. Start the MATLAB software.
2. At the MATLAB Command Window, type the following command:
nstp_plot('sines_auto_signaltap_0.txt') r
The MATLAB software displays a normalized plot of the DAC
CHANNEL A input similar to
Figure 2–11 .