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9
3. Apply power as specified in Section 4.4, click
on the
"Reset"
button and await the firmware
to download.
4. Click on the
"Close"
button to close the
System Settings window.
5. Navigate to the ADC121C021 Eval Board
Window. This is the Control Panel for the
device (
Figure 10
).
Figure 10: ADC121C021 Control Panel
6. Select the desired I
2
C Speed from the pull-
down menu (
Figure 11
).
Figure 11: ADC121C021 Control Panel
7. Set the I
2
C Slave Address (
Figure 10
). The
address will default to the correct address for
the ADC121C021 (54hex). If evaluating the
ADC121C027, the I
2
C address must be
changed to reflect the state of the address
selection pin (ADDR).
8. Press the “Read Registers” button. All of the
register fields will update (
Figure 10
).
9. Configure the ADC’s internal registers. The
Alert function and Automatic Conversion
Mode are setup through the Configuration
register. After making changes to a register
value, press the Enter key to write the register
(
Figure 10
).
10. To capture a dataset from the ADC, navigate
back to the main WaveVision window.
11. After the steps outlined in Section 3.2 are
completed, click on ‘Acquire’ then ‘Samples’
from the Main Menu (you can also press the
F1
shortcut key). If a dialog box opens, select
‘Discard’ or press the
Escape (Esc)
key to
start collecting new samples.
5.2 Data Analysis
WaveVision main menu will display an output plot.
Make sure there is no clipping of data samples.
Click on the software histogram tab and ensure
data does not exceed the limits of the device. The
samples may be further analyzed by clicking on
the magnifying glass icon, then clicking and
dragging across a specific area of the plot for
better data inspection (
Figure 12
). See the
WaveVision 4 Board User's Guide for more
details.
Figure 12: Software Histogram: Sine Wave Input
