Cirrus Logic CapturePlus II User Manual
CapturePlus II
High-speed Data Acquisition System
Features
High-speed Data Acquisition & Analysis Tool
Acquisition System Greatly Simplifies Capturing Data from
Cirrus Logic Industrial Evaluation Boards
LabVIEW
Real-time Data Capture
Frequency Domain, Time Domain, and Statistical Analysis
Convenient USB Interface to a Windows
Provides 100% Electrical Isolation Between the Capture
System & the Evaluation Board
®
-based Data Capture Software
– Save Data Captures for Later Analysis
®
-based PC
General Description
The CapturePlus™ II data ac quisition system is a development
tool that interfaces a Cirrus Logic evaluation board to a PCcompatible computer. Digital data is collected in a high-speed
digital FIFO, then transferred to the PC over a USB connection.
Evaluation software is included to analyze the data and demonstrate the ADC’s performance.
The data acquisition system is designed to be easily interfaced
to Cirrus Logic evaluation boards. The supplied host interface
software configures the CapturePlus II interface board allowing
the same hardware to be used with a variety of Cirrus Logic
ADC development systems.
The host interface software includes advanced statistical analysis functionality. The software was developed using National
Instruments LabVIEW
strument control and data acquisition and analysis
applications. The evaluation software permits time domain, frequency domain, and histogram analysis.
ORDERING INFORMATION
CDB-CAPTPL2 CapturePlus II System
®
, a software development system for in-
Cirrus Logic
Evaluation Board
(Available Separately)
www.cirrus.com
Copyright © Cirrus Logic, Inc. 2008
(All Rights Reserved)
MAR ‘08
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CapturePlus II
TABLE OF CONTENTS
1. CAPTUREPLUS II HARDWARE OVERVIEW ..........................................................................3
1.1 Kit Contents ........... ... .... ... .......................................... ... .......................................... ........... 3
1.2 Required Items Not Supplied .............................................................................................3
1.3 Minimum PC System Requirements .................................................................................. 3
2. SOFTWARE SETUP .................................................................................................................4
3. HARDWARE SETUP ................................................................................................................ 5
4. SOFTWARE DESCRIPTION ....................................................................................................6
4.1 Data Control Sub-panels ....................................................................................................6
4.1.1 Device Sub-panel ................................ ... .... ... ... ... .......................................... ... .... . 7
4.1.2 Acquire Sub-panel ..................... .... ... ... .......................................... ... .... ... ... ... ........7
4.1.3 View Sub-panel .......................................................... ... ... ... .... ... ........................... 9
4.1.4 Data Sub-panel ............................. ... ... ... .... ... ... ... .... ......................................... .... . 9
4.1.5 Quit Sub-panel .......................... .... ... ... .......................................... ... .... .................9
4.1.6 Status Sub-panel ....................... .... ... ... ... .......................................... .... ... ... ... ........9
4.2 Menu Tabs ................ .... .......................................... ... .......................................... ... ......... 10
4.2.1 Communication Configuration Tab ......................................................................11
4.2.2 General Configuration Tab ..................................................................................13
4.2.3 ADC Configuration Tab ........................................................... ... ... ... .... ... ... .........14
4.2.4 Configuration Tab ...................... .... ... ... .......................................... ... .... ... ............15
4.2.5 Time Domain Tab ................................................................................................16
4.2.6 Frequency Domain Tab ....................................................................................... 17
4.2.7 Histogram Tab ........................ ... .... ... ... .......................................... ... .... ... ... .........19
4.2.8 About Tab ......................... ... .......................................... ... ... ................................ 20
5. CONFIGURING THE CAPTUREPLUS II SYSTEM ................................................................ 21
5.1 Communication Configuration ............................. .... ... ... ... .... ... ... ... ... .... ... ... ... .... ... ............21
5.2 Selecting the Cirrus Logic Evaluation Board Type ............... ... ... ... ... .... ... .........................23
Appendix A. Testing the Cirrus Logic CDB556x/7x/8x Evaluation Board............................. 24
A.1 Baseline Testing for Noise & Distortion........................................................................... 24
A.2 Measuring Analog Input Signals...................................................................................... 32
Appendix B. Recommendations for Maximum Performance................................................. 39
Appendix C. FFT Window Leakage........................................................................................... 40
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1. CAPTUREPLUS II HARDWARE OVERVIEW
CapturePlus II
Hardware
CapturePlus II
Board A
(ARM9)
Indicator
LEDs
USB
Driver
Ethernet
Driver
DSP
Operating
System
ROM
DSP
Data
Acquisition
Memory
(RAM)
FPGA
1.1 Kit Contents
The following items are included in the CapturePlus II kit.
– Cirrus Logic ARM9-based Control/Communications Board
– CapturePlus II Data Acquisition Software on CDROM
– RS-232 9-pin Null Modem Cable
–USB Cable
Board B
(Interface)
Electrical Isolation
Electrical Isolation
Electrical Isolation
Cirrus Logic
Evaluation
Board
– Power Supply (Does not supply power to the evaluation board.)
1.2 Required Items Not Supplied
The following items are required to use the CapturePlus II system and are not included in the kit.
– Cirrus Logic Evaluation Board and Data Sheet
– Power Supplies to Run the Evaluation Board (varies depending on evaluation board used)
– PC Running Windows
®
2000 or Later or Windows NT® and an Available USB 2.0 Port
– Internet Access to Download any CapturePlus II Software Updates from
www.cirrus.com/Industrialsoftware
.
1.3 Minimum PC System Requirements
The PC system requirements for the Cirrus Logic CapturePlus II system are:
– Windows 2000 or Later or Windows NT
– Intel
– Video Resolution of 1024 x 768 or Greater
– Minimum 1 GB RAM (2 GB recommended for large data captures)
– Minimum 100 MB Free Hard Drive Space
®
Pentium® 600 MHz or Higher CPU
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CapturePlus II
2. SOFTWARE SETUP
The following section assumes the software is being installed from the CD-ROM included in the kit. The complete
software install package and any software updates can be downloaded from www.cirrus.com/Industrialsoftware
1. Insert the CapturePlus II CDROM into the PC.
2. If the CapturePlus II installer program does not start automatically, navigate to the CDROM root directory
and run the SETUP.EXE program.
.
3. Follow the instructions presented by the CapturePlus II Installation Wizard. The default GUI installation location is C:\Program Files\Capture_Plus_II\. The default runtime engine installation location is
C:\Program Files\National Instruments\.
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CapturePlus II
3. HARDWARE SETUP
The following section describes the connections between the Cirrus Logic evaluation board and the Ca pturePlus II system. It then describes the connections between the CapturePlus II system and the PC.
CapturePlus II
Data Capture Hardware
Digital Inputs
Digital Outputs
Included Power
Supply
USB Port
Serial Port
IBM-compatible PC
Running CapturePlus II
Software
Analog
Signal
Source
Cirrus Logic
Evaluation Board
ADC &
Associated Analog Circuitry
Electrical Isolation
External Power
Supplies
(Not Included)
1. Plug the ADC evaluation board into the connectors on the top of the CDBXC2S50 board.
2. Connect the USB cable between the Capture P lus II USB connector and the PC USB port.
3. With the CapturePlus II system power switch in the OFF position, plug the brick power supply into the
CapturePlus II system. Plug the power supply into a 100-240 VAC, 50/60 Hz, 1.0 A outlet.
4. Connect the
required power supplies to the appropriate connectors on the evaluation board.
5. Slide the CapturePlus II system power switch to the ON position. Press and release the Reset (/POR)
switch, S3.
6. Turn on the power supplies connected to the evaluation board.
7. Start the CapturePlus II software.
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CapturePlus II
4. SOFTWARE DESCRIPTION
The CapturePlus II Software user interface is divided into two sections:
– The data control sub-panels are located on the left-hand side and bottom of the GUI display and
are always available.
– The tabs at the top of the GUI panels are always present and provide convenient access to
configuration and data collection panels.
– Click on a tab to display the desired panel.
4.1 Data Control Sub-panels
The data control sub-panels are located on the left-hand side and bottom of the GUI display. They are
always visible.
Sub-panel Descriptions:
– Device: Configures the CapturePlus II system to capture data from the evaluation board.
– Acquire: Configures software parameters for acquiring data sets from the evaluation board.
– View: Selects the analog input channel for which data is displayed.
– Data: Save, load, or clear the data set in PC memory.
– Quit: Exits the software.
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CapturePlus II
4.1.1 Device Sub-panel
The Device sub-panel configures the CapturePlus II system to capture data from the evaluation board.
This sub-panel is always available.
Sub-panel Descriptions:
– Pull-down menu: The pull-down menu selects the Cirrus Logic evaluation board and associated
device. In most cases, the software will read the evaluation board EEPROM and automatically
select the appropriate menu item.
– Load Config: Loads the ADC internal register configuration file. Information in the configuration
file can be used to configure ADC internal registers. However, this function is not supported for all
Cirrus Logic ADCs.
– Save Config: Saves the ADC internal register configuration file. The software makes a copy of the
ADC internal register configuration and saves it in the configuration file.
4.1.2 Acquire Sub-panel
The Acquire sub-panel configures the software parameters for acquiring data sets from the evaluation
board. This sub-panel is always available. Click on the Acquire button to open this sub-panel.
Sub-panel Descriptions:
– Number of Samples to Capture: Selects number of data samples to acquire. Note: Capturing
data sets is PC memory intensive. The PC requires sufficient memory to run the PC operating
system, CapturePlus II software, and to store captured data sets. Insufficient memory may limit the
ability to acquire larger data sets. A minimum of 1 gigabyte of RAM is recommended.
– Data Format: Displays the format of the data samples being acquired. The software automatically
fills in the Data Format window based upon the evaluation board part number displayed in the
Device sub-panel. Change the data format between Bipolar and Unipolar by activating the adjacent
Up/Down buttons.
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CapturePlus II
– Timed Conversion or Continuous Conversion: Click on the toggle switch to change between
Timed Conversion and Continuous Conversion modes.
In Timed Conversion mode the CapturePlus II system forces the Desired Sample Rate to be met
by applying the correct timing delay to the ADC trigger. Enabling Timed Conversion mode activates
the Desired Conversion Rate window. Timed conversion sample rates are calculated based on
the frequency displayed in the Clock Frequency window. Not all Cirrus Logic ADCs support Timed
Conversion mode operation.
In Continuous Conversion mode the ADC is free running: the data sample rate is determined by
how fast the free running ADC converts data. This creates a conversion window equal to or less
than the Desired Conversion Rate value.
– Desired Sample Rate: Displays the ADC data acquisition sample rate. The software automatically
fills in the Desired Sample Rate field with a default value based upon the evaluation board part
number displayed in the Device sub-panel. Change the Desired Sample Rate by activating the
adjacent Up/Down buttons, or by clicking on the text box and manually entering a new value. Note
that Timed Conversion mode must be selected for this control to work.
– Channel(s) to Sample: Configures which analog input channel(s) to sample. When the OK button
is pressed, the requested number of samples are collected from the evauation board and are split
among the enabled channels. For example, with two channels selected, the CapturePlus II system
will collect (Number of Samples to Capture / 2) samples per channel. Not all Cirrus Logic evaluation
boards support multiple channels.
– Enabled Averaged FFT: Enable FFT averaging by clicking on the Enabled Averaged FFT box.
The box will become active, and the Averages control window will become available.
– Averages: Displays the number of contiguous data sets to be acquired for generating an averaged
FFT within the Frequency Domain tab. The Averages field can be changed by activating the
adjacent Up/Down buttons, or by clicking on the text box and manually entering a new value. To
activate the Averages window see the description on configuring the Enabled Average d FFT box.
Note that doubling the number of data sets being averaged decreases the FFT spot noise floor by
3 dB, allowing more detailed spectral analysis.
– Clock Frequency: Displays the ADC master clock frequency. The software automatically fills in
the Clock Frequency window with a default value based upon the evauation board part number
displayed in the
Clock Frequency can be changed by applying an external clock source and changing the Clock
Frequency window to reflect the new master clock frequency.
– Actual Sample Rate: Displays sample rate used by the CapturePlus II system when the system
controls the conversion rate.
– OK: Clicking this button initiates the data acquisition sequence.
– Cancel: Closes the Capture From ADC data acquisition sub-panel and no data acquisition
sequence is initiated.
– Abort: Halts data collection at the end of the current data set collection cycle (on Device sub-
panel).
Device sub-panel and is the default value for the evaluation board detected. The
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CapturePlus II
4.1.3 View Sub-panel
Use the View sub-panel to select the evaluation board analog input channel data set on which the software performs calculations and plots data graphs. This sub-panel is always available, however there may
be only one channel’s data set available for viewing.
4.1.4 Data Sub-panel
Use the Data sub-panel to save, load, or clear the present ADC data set. This sub-panel is always available.
Sub-panel Descriptions:
– Save Data: Saves current data set to a memory storage drive / device. There are two file formats
and three options for saving data:
CapturePlus II Format (.ad2): Use the CapturePlus II Format (.ad2) option to save the
unprocessed data set. Only the last captured data set can be saved. If multiple data sets have been
captured to generate an averaged FFT, only the last captured data set can be saved.
Save FFT Graph Information (.csv): Use the Save FFT Graph Information (.csv) option to save
the plotted FFT bin data, ADC test circuit performance data, and initial test conditions information.
This file option becomes available after the software is finished plotting an FFT within the
Frequency Domain tab. Use this option to save the bin data for either a single data set FFT or an
averaged data set FFT.
Save Histogram Graph Information (.csv): Use the Save Histogram Graph Information (.csv)
option to save the histogram bin data. To make this option available select the Histogram tab and
click on the Analyze button. This action creates the histogram bin data from the raw data set. Only
the most recent histogram bin data set can be saved. If multiple data sets ha ve been captured only
the last captured data set can be saved.
NOTE: Loading .csv format files is not supported.
– Load Data: Loads the .ad2 format data set from memory storage drive / device.
– Clear Data: Clears last data set stored in PC memory.
– Acquisition Time: Displays the real time clock and time stamp for the data set being captured.
4.1.5 Quit Sub-panel
The Quit sub-panel provides a Quit button for exiting the software. This sub-panel is always available.
4.1.6 Status Sub-panel
The Status sub-panel reports the status of the most recent software action taken. This sub-panel is al-
ways available.
The Status sub-panel will indicated when data is ready to be analyzed within the Frequency Domain and
Histogram tabs.
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CapturePlus II
4.2 Menu Tabs
The menu tabs are always present at the top of the software panels and provide access to configuration
and data collection panels. The menu tab selects the currently displayed panel.
Sub-panel Descriptions:
– Communication Configuration: Displays the Communication Configuration panel.
– General Configuration: Displays the scaling configuration for all software-generated graphs and
calculations.
– ADC Configuration: Displays the ADC Configuration panel.
– Configuration: Displays the Configuration panel.
– Time Domain: Displays the Time Domain analysis panel.
– Frequency Domain: Displays the Frequency Domain analysis panel.
– Histogram: Displays the Histogram panel for statistical analysis.
– About: Displays the About panel.
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CapturePlus II
4.2.1 Communication Configuration Tab
The Communication Configuration panel establishes the communications link between the CapturePlus
II system and the PC running the software. Select the Communication Configuration tab to display this
panel. Click on any other tab to exit this panel.
The Communication Configuration panel consists of the following sub-panels:
– Selected Device Address: Displays communication address selected.
– Detected Devices: Displays USB and Serial Port addresses available for selection.
– General Communications: Displays default port configurations for both the serial port and the
USB port. (Communication using the Ethernet port is not supported at this time.)
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CapturePlus II
USB Communications
A USB communication link must be established between the PC and th e CapturePlus II hardware befo re
the CapturePlus II system can operate.
To open communication to a USB connection perform the following steps:
– Select an available USB device address by double clicking on a USB address within the Detected
Devices sub-panel. The selected address will appear in the Selected Device Address sub-panel,
the Connect USB and Clear Device Address buttons will become available, and the Disconnect
button will be unavailable.
– Click on the Connect USB button. When USB communication is established, the Connected
indicator at the bottom right corner of the screen will become bright green and read “Connected”.
The Connect USB and Clear Device Address buttons will become unavailable. The Disconnect
button will become available.
To close communication to a USB connection perform the following steps:
– Click on the Disconnect button. When USB communication is disconnected, the Connected
indicator will turn gray and read “Disconnected”. The Connect USB and Clear Device Address
buttons will become available.
– To remove a USB device address from the Selected Device Address sub-panel, click on the Clear
Device Address button.
Serial Port Communications
Serial port communications between the PC and the CapturePlus II hardware is NOT required for the CapturePlus II system to operate.
12 DS789UM2
CapturePlus II
4.2.2 General Configuration Tab
The General Configuration tab provides access to configure the scaling for all software-generated data
graphs and calculations. Click on any other tab to exit this panel.
The General Configuration panel contains the following sub-panels:
Scaling: Use this button to select the magnitude units used for all software-generated data graphs
and calculations. Click on the button to toggle the magnitude units between Codes (ADC output
codes) and Voltage (scaled voltage).
Reference Inputs: This function provides x-axis magnitude scaling for all software-generated data
graphs. The software automatically fills in the Reference Inputs voltage (the maximum absolute
input voltage), based upon the evaluation board part number displayed in the Device sub-p anel.
The voltage displayed provides the 0 dB FS baseline magnitude scaling for all software-generated
data graphs. If the voltage reference device is changed, rescale the data graphs manually by
entering a new Reference Inputs voltage. The data graphs are scaled by the ratio of the new
voltage entered divided by the original 0 dB FS baseline voltage.
Note: This value should only be changed if the voltage reference on the ADC evaluation board is
changed, otherwise the voltage scaling will be incorrect. In addition, any modifications to the analog
input circuitry must be evaluated for effects on voltage scaling.
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