Software Description - Analog Devices EVAL-AD7723CB Quick Start Manual

SOFTWARE DESCRIPTION

The software which controls the Eval-Control Board and
hence the AD7723 evaluation board has three main screens.
The screen shown in Figure 3 is the screen which appears
when the software is run. The main function of this screen
is to allow the user to read a predetermined number of
samples from the AD7723 evaluation board and display
them in both the time and frequency domain. The screen
can be divided into three sections.
The upper third of the screen contains the control buttons,
the menu bar and various status windows.
buttons allow the user to take samples, reset the part and
quit the program. The menu bar allows the user to enter
the setup menu, select which printer port is being used to
control the Eval-Control Board, load and save samples, get
information about the software etc.
indicate the setup of the AD7723 evaluation board/device,
number of samples taken, and any information/error mes-
sages that are generated.
The middle third of the screen is a Digital Storage
Oscilloscope (DSO). When samples are uploaded from
the Eval-Control Board, they are displayed here.
samples can be displayed as either integer values or as
voltages. Once samples have been displayed, clicking at
any point in the graph will display the sample number and
REV. B
Figure 3: Main Screen - FFT Mode
the value of the point directly beneath the cursor. Along the
axis of the graph are the Zoom Handles. These allow the
user to zoom in and out to get a closer look at a particular
sample if required. When another set of samples is taken,
the graph will attempt to display all values collected unless
the Hold Zoom check box is ticked. In this case, the graph
will keep the same axis settings as for the previous set of
data samples. Additional check boxes are provided to give
the user control over the vertical and horizontal grids and
data points.
The control
The lower third of the screen will show either a Fast
Fourier Transform (FFT) of the data or a Histogram
which shows the number of occurrences of each particular
code read back. The FFT (the default option) is typically
used when the user is concerned with examining an ADC's
The status windows
performance in the frequency domain.
a Fourier Transform, the data can be windowed by a
Blackman-Harris window before the transform by clicking
the B-H box. When the B-H box is not clicked on, the data
is not windowed.
of the ADC's performance to DC signals.
displayed can be toggled by clicking on the FFT Mode/
The
Histogram Mode button in the top right of the screen.
Figure 4 shows how the main screen looks when the
Histogram Mode option is selected.
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EVAL-AD7723CB
When performing
The Histogram will give an indication
The option