XMAP Quick Start Guide
Contents
1. After you have collected sufficient data press the Stop button Note that run statistics including realtime livetime input and output count rates and the total number of events are displayed above the plot window Note also that MCA data for the current channel can be saved to a file by pressing Save Run 1 7 1 Selecting a Region of Interest ROI In order to calibrate the gain you must first select a region of interest Right click in the plot window and select Place Cursor 1 Drag the cursor to the center of an identifiable peak Right click on the cursor itself and select Auto ROI Notice that a region of interest around the peak has been created The ROI table below the plot window displays the upper and lower limits of the region the number of events enclosed the output count rate the Guassian mean and full width half maximum FWHM resolution If insufficient data has been collected the Auto ROI function may fail to properly select the peak Note that the ROI limits can be edited graphically by selecting and dragging the limits in the plot window or by editing the limit fields in the ROI table 1 7 2 Gain Calibration Enter the energy in kilo electron volts keV of the selected peak in the Calib keV field of the ROI table Press Calibrate ROI to automatically adjust the xMAP analog gain Acquire a new spectrum to verify that the gain has been calibrated Repeat until the peak centroid matches the specified energy to yo2. aware that thresholds set too low i e at or below noise levels can produce very poor performance A large noise peak near 0 eV in the spectrum and reduced output count rate are sure signs that one of the threshold settings is too low It is best to acquire a spectrum after each threshold adjustment monitoring the noise peak and the output count rate Be sure to save the INI file after thresholds have been optimized 1 9 Going Further There are many features and settings available in the current release that have not been documented yet gt The number of bins and MCA bin width can be changed in the Configuration settings tab gt The Dynamic Range setting along with the detector gain setting control the xMAP analog gain Assuming the detector gain is set properly an x ray with energy equal to the dynamic range setting will produce a step spanning 40 of the ADC input range X rays with energy greater than the dynamic range setting will not be processed efficiently Setting the dynamic range too low will produce a dead region at the high end of the spectrum setting it too high may result in degraded energy resolution if noise is not properly digitized Typically we recommend using a setting of approximately 40keV gt Baseline display and optimization Varying the number of Baseline Average samples in the Configuration settings tab can improve performance gt The Preset Run control above the plot window allows for various types of
3. fixed length runs gt The SCA settings tab contains controls for SCA data acquisition We recommend first selecting and ROI as described in 1 7 1 above for each desired SCA output then inserting them into the SCA table First click the desired ROI to make it active the press the Insert Active ROI button 1 10 Support Please email xManager software support questions to software _support xia com and hardware support questions to DXP xia com xManager can save most types of system information and data to external files to aid in the support process gt The xManager log file xManager log is located in your xManager directory The file contents can be viewed at any time by selecting the Log tab in the main plot window gt DSP settings can be viewed by selecting DSP Parameters from the Tools menu Press Export to File to create a complete DSP parameter settings file gt ADC Baseline and MCA data can be very useful when debugging a system To create these files simply press the Save button in the upper right hand corner of the respective plot window tab 9 6 2005 6
4. Manual XMAP Quick Start Guide XMAP QSG 0 7 1 1 XMAP Quick Start Guide This short document is intended to assist you in getting your XIA xMAP Digital Spectrometer PXI system up and running The xManager software operates on Windows 2000 XP machines The xMAP software and firmware is under continuing development as is the documentation A more thorough Getting Started Guide and a User s Manual will be provided in the near future Meanwhile refer to Chapters 4 6 of the Saturn User s Manual http www xia com Manuals Kepler_ Saturn Manual _4 0 2 pdf for more thorough discussion of the DXP spectrometer architecture All updates will be posted online at http www xia com DXP XMAP html 1 1 Software Installation Please close all applications that are currently running then double click on the file Setup exe included with the installation package Follow the steps as directed on screen We recommend that all users install all included components The xManager 0 7 installation will create a new directory C Program Files xia xManager 0 7 A new Start Menu gt Program group will also be created Do not attempt to run xManager until the xMAP hardware has been installed and the PXI system has been configured as described below 1 2 Hardware Installation XIA recommends using National Instruments PXI instrument crates and this document assumes this recommendation has been followed In any case please follow the instructions provided wit
5. Manual XMAP Quick Start Guide XMAP QSG 0 7 1 entering the spectrum If you don t know the reset time enter 100 microseconds Press Next 5 Detector Element Property Check the box Apply to All Detector Elements and enter the number of detector elements in your system Note that each xMAP Digital Spectrometer can process four independent detector elements Enter the polarity if xray steps generate a negative voltage step if xray steps generate a positive voltage step If you don t know the polarity keep the default negative setting Enter the gain in mV keV If you don t know the gain keep the default of 3 mV keV Press Next 6 PCI Configuration If you selected lt default blank template gt in step 2 above or you have changed the slot configuration or number of modules in your system select Use current system information This option will result in the parsing of the PXI system configuration file pxisys ini described in section 1 4 above such that xMAP modules located in the crate are organized from left to right If you selected an existing INI file in in step 2 above and would like to use the slot configuration or number of modules stored therein select Use the values from template file Press Next 7 xMap PCI Configuration This panel displays all located xMAP modules ordered from left to right In the future this panel will allow for arbitrary slot reordering Press Next 8 Save Completed Config
6. enter 3 and 9 Press Start Gain Matching to start the iterative process Use a higher Number of Iterations smaller of Calibration Energy and longer Acquisition Time s to increase the precision When you are satisfied with the results save your INI file 1 8 3 Decimation and Peaking Time As with all DXP spectrometers the XMAP decimates the ADC signal to extend the peaking time range i e 2 ADC samples are averaged to produce a single data point at the digital filter input where N is the decimation The ADC sampling period is 50ns Currently gt Decimation 0 4 samples point 100ns lt Peaking Time lt 500ns gt Decimation 2 4 samples point 500ns lt Peaking Time lt 8 00us gt Decimation 4 16 samples point 8 00us lt Peaking Time lt 32 0us gt Decimation 6 64 samples point 32 0us lt Peaking Time lt 128 0us The peaking time is set in the Configuration settings tab of the left hand settings panel To change the peaking time and decimation simply enter the new value in the Peaking Time text box and press Apply If the new peaking time crosses a decimation boundary you will hear relays clicking as xManager downloads new firmware to the xMAP modules 1 8 4 Thresholds As with all spectrometers proper threshold settings are key to optimum results The DXP employs up to three 3 digital filter paths each with it s own triggering threshold running simultaneously on the input signal Generally spea
7. h your crate and controller Note XIA PXI modules are NOT hot pluggable Never attempt to install or remove an xMAP Digital Spectrometer module while the instrument crate is powered on Such action can irreparably harm the module Turn off the host computer and PXI crate power Install x MAP modules in the PXI crate making sure that the cards are fully inserted and each card s handle is secured such that it protrudes horizontally Connect your detector outputs to the xMAP SMA input connectors We recommend using a moderate intensity x ray source with easily identifiable spectral lines Turn on the power for your detector and PXI crate 1 3 xMAP Driver Installation Restart the host computer Windows should automatically find the new hardware and start the Found New Hardware Wizard 1 Press Next to proceed to the Install Hardware Device Drivers page 2 Select Search for a suitable driver for my device recommended option and press Next to proceed to the Locate Driver Files page 3 Select Specify a location and press Next 4 Browse to or type C WINNT inf for Windows 2000 or C Windows inf for Windows XP and press OK 5 Windows should find the file xmap9054 inf in the specified directory Press Next to complete the driver installation 6 Repeat steps 1 5 for each xMAP module installed 9 6 2005 Manual XMAP Quick Start Guide XMAP QSG 0 7 1 1 4 PXI System Configuration In order to properly ide
8. king a longer filter length produces better noise reduction but worse time resolution gt The Trigger filter has a very short length typically fixed at 50ns 100ns and is used solely to identify the time of occurrence of incident x rays The Trigger threshold is typically set between 750 and 2000 eV gt The Baseline filter runs at exactly one fourth the peaking time This filter is used both for soft x ray detection and for generating the baseline average the smoothed baseline value that is subtracted from the pulse peak sample to yield the pulse height or energy The Baseline threshold can typically be set significantly lower than the Trigger filter however the precise setting depends on the peaking time For high resolution detectors and at longer peaking times the Baseline threshold can usually be set to 150 300 eV Note There is no Baseline filter present for peaking times at or below 500ns i e for decimation 0 gt The pulse peak sample is acquired at the Energy filter output This filter is the longest of the three and corresponds to the specified peaking time In rare cases this filter can be used for the detection of very soft x rays but in nearly all cases the threshold should be disabled by setting it to zero 9 6 2005 5 Manual XMAP Quick Start Guide XMAP QSG 0 7 1 Thresholds are set in the Configuration settings tab of the left hand settings panel Edit a threshold and press Apply to try a new setting Be
9. n from the File menu If you have previously run with xManager your registry settings will point to the most recently used INI file and xManager will automatically run with these settings upon startup 1 5 2 Creating an INI file using the Configuration Wizard Start xManager via the Start menu Start gt Programs gt xManager 0 7 gt xManager The first time xManager 0 7 starts up an xManager Configuration File Error will be generated Check the box Generate a new configuration file to launch the Configuration Wizard which guides the user step by step to create an INI file Note that the Configuration Wizard can also be launched at any time from the Tools menu in xManager 1 Welcome to the xMAP Configuration Wizard Press Next in the xMAP Configuration Panel 2 Starting Template Select lt default blank template gt and press Next Note that if you have an existing INI file you can select it instead to use as a template such that some data entry steps below are skipped 3 Firmware Press the FDD File button to browse or type C Program Files xia xManager 0 7 firmware xmap_revb fdd and press Next 4 Detector Configuration Select the appropriate detector type Currently only reset detectors are supported Enter the reset time period This is the time in microseconds that the preamplifier takes to reset and settle and should be set conservatively to prevent associated voltage transients from 9 6 2005 2
10. ntify slots in the crate xManager parses the PXI system configuration file pxisys ini National Instruments provides software for creating this file called Measurement and Automation Explorer or MAX If you have not already done so follow the instructions provided with your crate and controller to generate the system configuration file Verify that the file exists in C WINNT directory for Windows 2000 or C Windows directory for Windows XP 1 5 xManager System Configuration 1 5 1 Initialization Files xManager uses an initialization or INI file to store system information such as the number and slot location of xMAP modules in the system detector characteristics and spectrometer settings In order to start properly at minimum xManager needs to know gt The location of the xMAP firmware file DSP and FPGA code that runs on the board included in the installation package The number of xMAP modules in the system The type of detector preamplifier used i e reset or RC decay The polarity of the detector preamplifier The gain of the detector preamplifier in mV keV VVVV Y The reset time period for reset type detectors or the RC decay time for RC type detectors INI files can be updated at any time i e after the spectrometer settings have been optimized by selecting Save Configuration or Save Configuration As from the File menu Existing INI files can be loaded at any time by selecting Load Configuratio
11. ow and enter 1 microsecond in the Sampling Interval text box Press the adjacent Get Trace button to display 4000 points or 4 milliseconds of ADC data To zoom 9 6 2005 3 Manual XMAP Quick Start Guide XMAP QSG 0 7 1 hold the Ctrl key and click and drag in the plot window To pan click and drag on the plot axes To reset the display right click in the plot window and select Full Scale The plot window should display positive x ray steps i e with a rising edge riding on a negatively sloped baseline These steps should be between 50 500 ADC units in height You may also see much larger tracking steps that recover the ADC signal to midrange 8192 ADC units after it has drifted out of range or after the preamplifier reset has occurred If your signal matches this description proceed to section 1 7 below 1 6 2 Changing Detector Preamplifier Settings Select the Detector tab at the bottom of the left hand settings panel Change the polarity and preamplifier gain as necessary and press Apply When the signal looks as described above press Save to update your INI file You are now ready to acquire a preliminary spectrum and calibrate the gain 1 7 Spectrum Acquisition and Calibration Select the MCA tab at the bottom of the main plot window Press Start Run If the Continuous checkbox is selected the spectrum display will automatically update Otherwise press the Update button to manually refresh the display
12. ur satisfaction You may want to save you INI file again at this point 1 8 Spectrometer Settings and Optimization 1 8 1 Channel Selection Note that data is only displayed for the currently selected processing channel i e detector element The channel selection control is located in the upper lef hand corner below the File Tools and Help menus In most cases we recommend selecting the Apply to All checkbox such that settings changes are applied to all channels 9 6 2005 4 Manual XMAP Quick Start Guide XMAP QSG 0 7 1 1 8 2 Automatic Gain Matching If you select another channel you will likely find that the spectrum on that channel is not calibrated We have seen detector gains vary by 30 from element to element and many detectors drift significantly with temperature and time xManager allows for the calibrated gain of each channel to be saved and restored via the INI file Nonetheless because of drift you may need to recalibrate the system at regular intervals The gain matching function facilitates this task by automatically calibrating all selected channels simultaneously By default all channels are selected for gain matching To de select a channel click the Channels settings tab and click in the Skip field Now select the GainMatch tab below the main plot window Enter conservative upper and lower limits in the Lower and Upper fields of the Calibration Peak Range KeV For example if searching for a 5 9keV peak
13. uration The INI file you have created can now be saved Select a unique name for the file e g C Program Files xia xManager 0 7 xmap_32module ini Press Finish to save the INI file and exit the Configuration Wizard 1 5 3 Loading an INI file Select Load Configuration from the File menu Browse to and select the file that you just created and press Open xManager will download firmware and initialize the xMAP modules in your system 1 5 4 Saving an INI file INI files can be updated at any time i e after the spectrometer settings have been optimized by selecting Save Configuration or Save Configuration As from the File menu You may find it useful to maintain several INI files e g for operating with different detectors or with different spectrometer settings 1 6 Verifying the Detector Preamplifier Settings Before taking a spectrum it s a good idea to first verify that the preamplifier polarity and gain have been set properly Your detector should be powered and moderate intensity x rays should be present i e 10 000 counts per second per channel Note that under these conditions the xMAP front panel LEDs adjacent each input should be flashing green If they are not this is a good indication that your preamplifier signal polarity is incorrect 1 6 1 Viewing the X ray Signal Select the Traces tab at the bottom of the main plot window Select ADC from the drop down list at the top of the main plot wind
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