EVAL-AD7716EB Datasheet, PDF (4/12 Pages) Analog Devices – Evaluation Board For 22-Bit Data Acquisition System

EVAL-AD7716EB
SOFTWARE DESCRIPTION
The EVAL-AD7716EB comes complete with PC-compatible
software. This software runs under WINDOWS and is largely
button-driven. It consists of several pop-up screens which are
easily navigated. It allows the user to control and evaluate the
AD7716 over the printer port of the PC.
To use the software, the user must have an IBM-compatible PC
and Windows 3.1 must be installed. Start Windows and using
either the RUN command or the File Manager, start the
program called SETUP.EXE on the distribution disk. This
automatically installs the application and sets up a Windows
Group called "ANALOG DEVICES". The application icon is
found here. To start the application, double click on the icon.
When the program starts, the user is asked to select a printer
port. The correct selection depends on the type of computer
being used (Desktop, Laptop, etc,). LPT1 works for most
machines. LPT2 can be used for machines which have two
printer ports. When using a Compaq laptop, select PRN.
Once the printer port has been selected, the user can move to
the MAIN MENU. Once here, the program allows the follow-
ing functions:
Program the AD7716 Control Register
Reset the AD7716
Gather Data
Graph the Data
Do Noise Analysis
Do a Noise Histogram
Write to a File
Read from a File
BOARD CAPABILITIES
The EVAL-AD7716 allows the digital filter in the AD7716 to be
programmed for three cut-off frequencies. These are 36.5Hz,
73Hz and 146Hz. The device itself is capable of operating at
two other cut-off frequencies: 292Hz and 584Hz. However, at
these higer cut-off frequencies it is not possible to transfer all the
device data (128 bits) in the time available, given the speed of
the printer port interface. That is why the feature is not offered
with this package. If operation at these higher cut-off frequen-
cies is desired, then it is recommended that the user interface
the EVAL-AD7716EB to a microcontroller or a DSP micro-
computer over a faster serial port.
Because of the many calculations taking place in the program, a
situation can arise where the program can run out of stack
memory. This stack memory stores the variables that are being
used at that particular time. When this happens, either a
message comes up on the screen ("Out Of Stack Space") or the
program buttons cease to function. To resume normal opera-
tion, simply quit by double-clicking on the top left-hand corner
of the window, and restart the application.
Note that this is confined to the AD7716 program and does not
affect any other Windows program.
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REV. B