EVAL-AD7716EB Datasheet, PDF (6/12 Pages) Analog Devices – Evaluation Board For 22-Bit Data Acquisition System

EVAL-AD7716EB
PARALLEL PORT SELECTION
The AD7716 evaluation software allows the user to program and gather samples from the AD7716 evaluation
board via the printer port of a PC using the cable supplied. When the program starts up a window called Select A
Parallel Port appears (See Fig.1). The user can select the port they wish to use by clicking on the appropriate
option button and then clicking OK. The hexadecimal numbers displayed beside each option correspond to the
memory address of the port in question. The default selection LPT1 will work in most cases.
Fig. 1 Parallel Port Selection
THE MAIN MENU WINDOW
Once the OK button of the Port Selection window has been pressed the user is presented with the Main Menu
window for the application. The window is called AD7716 Evaluation Software and is shown in Fig. 2 below.
From it the user may :
•
Select the Filter Cutoff Frequency.
•
Program the states of the digital output pins Dout1 and Dout2.
•
Program these selections to the AD7716 Evaluation Board.
•
Read Data from the AD7716 Evaluation Board.
•
Save the data gathered to a file.
•
Load data saved at an earlier date.
•
Graph the data gathered.
•
Do Noise Analysis on the gathered data.
•
Display a Histogram of codes on the data gathered.
•
Quit the program.
Before data can be gathered from the AD7716 Evaluation Board the AD7716 Control Register must be pro-
grammed and the device must be reset. If ,on the Evaluation Board, the Cascin is connected to the Cascout via
LK1 then the AD7716 must be reset each time the Control Register is programmed. If the Cascin is connected
to the inverted DRDY via LK2 then resetting the AD7716 is only required once. When this has been done data
can be gathered and examined. Note that changing the "System Options" will not result in a change in the
Control Register of the AD7716 and it is only when the "Program AD7716" button is pressed that these options
are loaded to the AD7716.
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REV. B