Altera Cyclone III, Руководство по началу работы

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Chapter 5: Factory Designs 5–5
Analyzing the Data in the MATLAB Software
© August 2008 Altera Corporation DSP Development Kit, Cyclone III Edition Getting Started User Guide
Preliminary
5. To analyze the spectrum of the combined signal through the system from the
output to the D/A converter back to the input from the A/D converter, perform
the following steps:
a. In the MATLAB Command Window, type the following command:
sines_plot(‘sines_auto_signaltap_0.txt’,’b’)
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b. The MATLAB software opens a display window and displays a normalized
plot of the ADC CHANNEL A input similar to that shown in Figure 5–4 .
The plot represents the resulting signal with all of the system noise and
attenuation.
6. To analyze the final spectrum from the output of the 3-MHz FIR filter, in the
MATLAB Command Window, type the following command:
sines_plot(‘sines_auto_signaltap_0.txt’,’c’)
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The MATLAB software opens a display window and displays a normalized plot of
the output of the 3-MHz FIR filter (
Figure 5–5 ).
Figure 5–4. Normalized Spectral Plot of 14-bit ADC Channel A Output Data