CDB5460A Datasheet, PDF (18/28 Pages) Cirrus Logic – Evaluation Board and Software

CDB5460A
will appear on pressing the Collect button in the
Data Collection Window if any speed limits appear
to be exceeded, but the data collection will still take
place.
2.9.7 Accept Button
When this button is pressed, the current settings
will be saved, and the user will return to the Data
Collection Window.
2.10 Collecting Data Sets
To collect a sample data set:
1) In the Data Collection Window, press the Con-
fig button to bring up the Configuration Win-
dow and view the current settings.
2) Select the appropriate settings from the avail-
able options (see the section on the Configura-
tion Window) and press the Accept button.
3) The Data Collection Window should still be
visible. Press the Collect button to begin col-
lecting data. A progress indicator bar will ap-
pear at the bottom of the screen during the data
collection process.
4) Data is first collected from the CS5460A and
stored in SRAM, and then transferred from the
SRAM to the PC through the RS-232 serial ca-
ble. Depending on the value of the Cycle Count
Register and the number of samples being col-
lected, this process may take a long time. The
process can be terminated by pressing the Stop
button, but if this is done, the user should also
press Reset on the CDB5460A board.
5) Once the data has been collected, it can be ana-
lyzed, printed, or saved to disk.
2.11 Retrieving Saved Data From a File
The CDB5460A software allows the user to save
data to a file, and retrieve it later when needed. To
load a previously saved file:
1) Pull down the Setup option and select Disk. A
file menu will appear.
2) Find the data file in the list and select it. Press
the Select button to return.
3) Go to the Data Collection Window, and press
the Collect button.
4) The data from the file should appear on the
screen. To select a different file, repeat the pro-
cedure.
2.12 Analyzing Data
The evaluation software provides three types of
analysis tests - Time Domain, Frequency Domain,
and Histogram. The Time Domain analysis pro-
cesses acquired conversions to produce a plot of
Magnitude versus Conversion Sample Number.
The Frequency Domain analysis processes ac-
quired conversions to produce a magnitude versus
frequency plot using the Fast-Fourier transform
(results up to Fs/2 are calculated and plotted). Also,
statistical noise calculations are calculated and dis-
played. The Histogram analysis test processes ac-
quired conversions to produce a histogram plot.
Statistical noise calculations are also calculated and
displayed.
2.13 Histogram Information
The following is a description of the indicators asso-
ciated with Histogram Analysis. Histograms can be
plotted in the Data Collection Window by setting the
Time Domain / FFT / Histogram selector to Histo-
gram (Figure 8).
2.13.1 BIN
Displays the x-axis value of the cursor on the His-
togram.
2.13.2 MAGNITUDE
Displays the y-axis value of the cursor on the His-
togram.
2.13.3 MAXIMUM
Indicator for the maximum value of the collected
data set.
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