EVAL-AD7492CB

The EVAL-AD7492CB software which controls the Evaluation Board Controller and hence the evaluation board has three main screens. The screen shown in Figure 2 shows the screen which appears when the software is run. The main function of this EVAL-AD7492CB screen is to allow the user to read a predetermined number of samples from the evaluation board and display them in both the time and frequency domain. The screen can be divided into 3 sections. The upper third of the screen contains the control buttons, the menu bar and various status windows. The control buttons allow the user to enter the setup menu, take samples and get information about the software. The menu bar allows the user to select which printer port is to be used to control the Evaluation Board Controller, load and save data etc. The status windows indicate the setup of the evaluation board/device, number of samples taken and any information/error messages that are generated.

The middle third of the EVAL-AD7492CB screen is a Digital Storage Oscilloscope (DSO). When samples are uploaded from the Evaluation Board Controller they are displayed here. The samples can be displayed either as integer values or as voltages (determined by the input range of the device inquestion). Once samples have been displayed clicking at any point in the graph will display the sample number and 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 acloser 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 lower third of the EVAL-AD7492CB screen will show either a Fast Fourier Transform (FFT) of the data or a Histogram which shows the number of occurrances of each particular code read back. The FFT (the default option) is typically used when the user is concerned with examining an ADC's performance in the frequency domain while the Histogram will give an indication of the ADC's performance to DC signals. The option displayed can be toggled by clicking on the FFT Mode/Histogram Mode button in the top right of the screen. Figure 3 shows how the main screen looks when the Histogram Option is selected.