git-svn-id: https://subversion.xor.aps.anl.gov/synApps/areaDetector/trunk@7637 dc6c5ff5-0b8b-c028-a01f-ffb33f00fc8b
945 lines
43 KiB
HTML
Executable File
945 lines
43 KiB
HTML
Executable File
<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<title>areaDetector Pilatus driver</title>
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</head>
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<body>
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<center>
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<h1>
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areaDetector Pilatus driver</h1>
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<h2>
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September 17, 2008</h2>
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<h2>
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Mark Rivers</h2>
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<h2>
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University of Chicago</h2>
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</center>
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<br />
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<h2>
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Table of Contents</h2>
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<ul>
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<li><a href="#Introduction">Introduction</a></li>
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<li><a href="#StandardNotes">Implementation of standard driver parameters</a></li>
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<li><a href="#Driver_parameters">Pilatus specific parameters</a></li>
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<li><a href="#Unsupported">Unsupported standard driver parameters</a></li>
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<li><a href="#Screenshots">Screenshots</a></li>
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<li><a href="#Configuring">Configuring</a></li>
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<li><a href="#Performance measurements">Performance measurements</a> </li>
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<li><a href="#Hardware notes">Hardware notes</a> </li>
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<li><a href="#Restrictions">Restrictions</a> </li>
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</ul>
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<h2 id="Introduction" style="text-align: left">Introduction</h2>
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<p>
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This is a driver for the Pilatus pixel array detectors <a href="http://www.dectris.com">
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Dectris</a>. It inherits from ADDriver and implements many of the parameters in
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ADStdDriverParams.h. It also implements a number of parameters that are specific
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to the Pilatus detectors.</p>
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<p>
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The interface to the detector is via a TCP/IP socket interface to the <b>camserver</b>
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server that Dectris provides. The camserver program must be started before the areaDetector
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software is started, typically by running the <b>camonly</b> script provided by
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Dectris.
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</p>
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<p>
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The camserver program saves the data to disk as TIFF files. The areaDetector software
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reads these disk files in order to read the data, because camserver does not provide
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another mechanism to access the data.
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</p>
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<h2 id="StandardNotes" style="text-align: left">Implementation of standard driver parameters</h2>
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<p>
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The following table describes how the Pilatus driver implements some of the standard
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driver parameters.
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</p>
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<table border="1" cellpadding="2" cellspacing="2" style="text-align: left">
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<tbody>
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<tr>
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<td align="center" colspan="3">
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<b>Parameter Definitions in pilatusDetector.cpp and EPICS Record Definitions in pilatus.template</b></td>
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</tr>
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<tr>
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<th>
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Enum name</th>
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<th>
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EPICS record name</th>
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<th>
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Description</th>
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</tr>
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<tr>
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<td>
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ADTriggerMode</td>
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<td>
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$(P$(R)TriggerMode</td>
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<td>
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The driver redefines the choices for the ADTriggerMode parameter (record $(P)$(R)TriggerMode)
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from ADStdDriverParams.h. The choices for the Pilatus are:
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<ul>
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<li>Internal (external signal not used)</li>
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<li>External Enable (count while external trigger line is high, readout on high to
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low transition)</li>
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<li>External Trigger (begin acquisition sequence on high to low transition of external
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trigger line)</li>
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<li>Multiple External Trigger (high to low transition on external signal triggers
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a single acquisition for the programmed exposure time)</li>
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<li>Alignment (collect images as fast as exposure time and readout permit, images
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written to a temporary file)</li>
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</ul>
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The first 4 modes correspond directly to the camserver commands <code>Exposure</code>,
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<code>ExtEnable</code>, <code>ExtTrigger</code>, and <code>ExtMTrigger</code> respectively.
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Alignment mode uses the <code>Exposure</code> command as well, but continuously
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takes images into the same temporary file (<code>alignment.tif</code>).
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</td>
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</tr>
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<tr>
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<td>
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ADExposureTime</td>
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<td>
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$(P$(R)ExposureTime</td>
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<td>
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In External Enable mode this value is not used by camserver. However, it should
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be set larger than the maximum time exposure time from the external source, so that
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pilatusROI.st can estimate how long to wait for the data files to be created before
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timing out.</td>
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</tr>
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<tr>
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<td>
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ADNumImages</td>
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<td>
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$(P$(R)NumImages</td>
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<td>
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Controls the number of images to acquire. It applies in all trigger modes except
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Alignment.</td>
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</tr>
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<tr>
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<td>
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ADExposurePeriod</td>
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<td>
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$(P$(R)ExposurePeriod</td>
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<td>
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Controls the exposure period in seconds. It is only in Internal or External Trigger
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modes when NumImages > 1.</td>
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</tr>
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<tr>
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<td>
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ADNumExposures</td>
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<td>
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$(P$(R)NumExposures</td>
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<td>
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Controls the number of exposures per image. It is only used in External Enable mode.</td>
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</tr>
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<tr>
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<td>
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ADAquire</td>
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<td>
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$(P$(R)Acquire</td>
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<td>
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Controls the acquisition. Setting this to 1 starts image acquisition. The driver
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sets the record to 0 when acquisition is complete. This means an entire acquisition
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series if NImages > 1. Setting this to 0 aborts an acquisition. If the driver
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was currently acquiring imges then this record will cause the "Stop" and "K" (Kill)
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commands to be sent to camserver.</td>
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</tr>
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<tr>
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<td>
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ADFilePath</td>
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<td>
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$(P$(R)FilePath</td>
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<td>
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Controls the path for saving images. It must be a valid path for camserver <i>and</i>
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for the areaDetector driver, which is normally running in an EPICS IOC. If camserver
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and the EPICS IOC are not running on the same machine then soft links will typically
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be used to make the paths look identical.</td>
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</tr>
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<tr>
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<td>
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ADFileFormat</td>
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<td>
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$(P)$(R)FileFormat</td>
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<td>
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camserver uses the file extension to determine what format to save the files in.
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The areaDetector Pilatus driver only supports TIFF files, so the extension should
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be .tif. When saving multiple images (NImages>1) camserver has its own rules for
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creating the names of the individual files. The rules are as follows. The name constructed
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using the algorithm described for ADFileTemplate in <a href="areaDetectorDoc.html">
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areaDetectorDoc.html</a> is used as a basename. The following examples show the
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interpretation of the basename.
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<pre> Basename Files produced
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test6.tif test6_00000.tif, test6_00001.tif, ...
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test6_.tif test6_00000.tif, test6_00001.tif, ...
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test6_000.tif test6_000.tif, test6_001.tif, ...
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test6_014.tif test6_014.tif, test6_015.tif, ...
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test6_0008.tif test6_0008.tif, test6_0009.tif, ...
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test6_2_0035.tif test6_2_0035.tif, test6_2_0036.tif, ...
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</pre>
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The numbers following the last '_' are taken as a format template, and as a start
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value. The minimum format is 3; there is no maximum; the default is 5. The format
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is also constrained by the requested number of images.</td>
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</tr>
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</tbody>
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</table>
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<p>
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It is useful to use NDPluginROI to define an ROI containing the entire Pilatus detector.
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This ROI can be monitored to make sure that the 20-bit limit of 1,048,575 is not
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being approached in any pixel.
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</p>
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<h2 id="Driver_parameters" style="text-align: left">Pilatus specific parameters</h2>
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<p>
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The Pilatus driver implements the following parameters in addition to those in ADStdDriverParams.h:
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</p>
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<table border="1" cellpadding="2" cellspacing="2" style="text-align: left">
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<tbody>
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<tr>
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<td align="center" colspan="7">
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<b>Parameter Definitions in pilatusDetector.cpp and EPICS Record Definitions in pilatus.template</b></td>
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</tr>
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<tr>
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<th>
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Enum name</th>
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<th>
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asyn interface</th>
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<th>
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Access</th>
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<th>
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Description</th>
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<th>
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drvUser string</th>
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<th>
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EPICS record name</th>
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<th>
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EPICS record type</th>
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</tr>
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<tr>
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<td>
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PilatusDelayTime</td>
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<td>
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asynFloat64</td>
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<td>
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r/w</td>
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<td>
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Delay in seconds between the external trigger and the start of image acquisition.
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It only applies in External Trigger mode</td>
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<td>
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DELAY_TIME</td>
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<td>
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$(P)$(R)DelayTime</td>
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<td>
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ao</td>
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</tr>
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<tr>
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<td>
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PilatusThreshold</td>
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<td>
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asynFloat64</td>
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<td>
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r/w</td>
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<td>
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Threshold energy in keV</td>
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<td>
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THRESHOLD</td>
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<td>
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$(P)$(R)ThresholdEnergy</td>
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<td>
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ao</td>
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</tr>
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<tr>
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<td>
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N/A</td>
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<td>
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N/A</td>
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<td>
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r/w</td>
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<td>
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Gain menu. Controls the value of Vrf, which determines the shaping time and gain
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of the input amplifiers. The allowed values are:
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<ul>
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<li>0 ("Fast/Low") Fastest shaping time (~125ns) and lowest gain. </li>
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<li>1 ("Medium/Medium") Medium shaping time (~200 ns) and medium gain. </li>
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<li>2 ("Slow/High") Slow shaping time (~400 ns) and high gain. </li>
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<li>3 ("Slow/Ultrahigh") Slowest peaking time (? ns) and highest gain. </li>
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</ul>
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</td>
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<td>
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N/A</td>
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<td>
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$(P)$(R)GainMenu</td>
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<td>
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mbbo</td>
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</tr>
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<tr>
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<td>
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PilatusArmed</td>
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<td>
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asynInt32</td>
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<td>
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r/o</td>
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<td>
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Flag to indicate when the Pilatus is ready to accept external trigger signals (0=not
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ready, 1=ready). This should be used by clients to indicate when it is OK to start
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sending trigger pulses to the Pilatus. If pulses are send before Armed=1 then the
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Pilatus may miss them, leading to DMA timeout errors from camserver</td>
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<td>
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ARMED</td>
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<td>
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$(P)$(R)Armed</td>
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<td>
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bi</td>
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</tr>
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<tr>
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<td>
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PilatusTiffTimeout</td>
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<td>
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asynFloat64</td>
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<td>
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r/w</td>
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<td>
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Timeout in seconds when reading a TIFF file. It should be set to several seconds,
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because there can be delays for various reasons. One reason is that there is sometimes
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a delay between when an External Enable acquisition is started and when the first
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external pulse occurs. Another is that it can take some time for camserver processes
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to finish writing the files.</td>
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<td>
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TIFF_TIMEOUT</td>
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<td>
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$(P)$(R)ReadTiffTimeout</td>
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<td>
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ao</td>
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</tr>
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<tr>
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<td>
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PilatusBadPixelFile</td>
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<td>
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asynOctet</td>
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<td>
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r/w</td>
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<td>
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Name of a file to be used to replace bad pixels. If this record does not point to
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a valid bad pixel file then no bad pixel mapping is performed. The bad pixel map
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is used before making the NDArray callbacks. It does not modify the data in the
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files that camserver writes. This is a simple ASCII file with the following format:
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<pre> badX1,badY1 replacementX1,replacementY1
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badX2,badY2 replacementX2,replacementY2
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...
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</pre>
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The X and Y coordinates range from 0 to NXPixels-1 and NYPixels-1. Up to 100 bad
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pixels can be defined. The bad pixel mapping simply replaces the bad pixels with
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another pixel's value. It does not do any averaging. It is felt that this is sufficient
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for the purpose for which pilatusROI was written, namely fast on-line viewing of
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ROIs and ImageData. More sophisticated algorithms can be used for offline analysis
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of the image files themselves. The following is an example bad pixel file for a
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GSECARS detector:
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<pre> 263,3 262,3
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264,3 266,3
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263,3 266,3
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300,85 299,85
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300,86 299,86
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471,129 472,129
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</pre>
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</td>
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<td>
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BAD_PIXEL_FILE</td>
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<td>
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$(P)$(R)BadPixelFile</td>
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<td>
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waveform</td>
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</tr>
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<tr>
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<td>
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PilatusNumBadPixels</td>
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<td>
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asynInt32</td>
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<td>
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r/o</td>
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<td>
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The number of bad pixels defined in the bad pixel file. Useful for seeing if the
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bad pixel file was read correctly.</td>
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<td>
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NUM_BAD_PIXELS</td>
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<td>
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$(P)$(R)NumBadPixels</td>
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<td>
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longin</td>
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</tr>
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<tr>
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<td>
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PilatusFlatFieldFile</td>
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<td>
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asynOctet</td>
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<td>
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r/w</td>
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<td>
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Name of a file to be used to correct for the flat field. If this record does not
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point to a valid flat field file then no flat field correction is performed. The
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flat field file is simply a TIFF file collected by the Pilatus that is used to correct
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for spatial non-uniformity in the response of the detector. It should be collected
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with a spatially uniform intensity on the detector at roughly the same energy as
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the measurements being corrected. When the flat field file is read, the average
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pixel value (averageFlatField) is computed using all pixels with intensities > PilatusMinFlatField.
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All pixels with intensity < PilatusMinFlatField in the flat field are replaced with
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averageFlatField. When images are collected before the NDArray callbacks are performed
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the following per-pixel correction is applied:
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<pre> ImageData[i] = (averageFlatField * ImageData[i])/flatField[i];
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</pre>
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</td>
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<td>
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FLAT_FIELD_FILE</td>
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<td>
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$(P)$(R)FlatFieldFile</td>
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<td>
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waveform</td>
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</tr>
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<tr>
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<td>
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PilatusMinFlatField</td>
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<td>
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asynInt32</td>
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<td>
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r/w</td>
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<td>
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The mimimum valid intensity in the flat field. This value must be set > 0 to prevent
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divide by 0 errors. If the flat field was collected with some pixels having very
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low intensity then this value can be used to replace those pixels with the average
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response.</td>
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<td>
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MIN_FLAT_FIELD</td>
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<td>
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$(P)$(R)MinFlatField</td>
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<td>
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longout</td>
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</tr>
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<tr>
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<td>
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PilatusFlatFieldValid</td>
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<td>
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asynInt32</td>
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<td>
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r/o</td>
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<td>
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This record indicates if a valid flat field file has been read. 0=No, 1=Yes.</td>
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<td>
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FLAT_FIELD_VALID</td>
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<td>
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$(P)$(R)FlatFieldValid</td>
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<td>
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bi</td>
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</tr>
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<tr>
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<td>
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N/A</td>
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<td>
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N/A</td>
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<td>
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N/A</td>
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<td>
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asyn record to control debugging communication with camserver. Setting the CNCT
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field in this record to <code>Disconnect</code> causes the drvAsynIPPort server
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to disconnect from camserver. This can be used to allow another program, such as
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TVX, to temporarily take control of camserver, without restarting the EPICS IOC.
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Set CNCT to <code>Connect</code> to reconnect the IOC to camserver, or simply process
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any record which communicates with camserver, because the driver will automatically
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reconnect.</td>
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<td>
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N/A</td>
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<td>
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$(P)$(R)CamserverAsyn</td>
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<td>
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asyn</td>
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</tr>
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</tbody>
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</table>
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<h2 id="Configuration" style="text-align: left">Configuration</h2>
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<p>
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The Pilatus driver is created with the following command, either from C/C++ or from
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the EPICS IOC shell.
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</p>
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<pre> pilatusDetectorConfig(const char *portName, const char *camserverPort,
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int maxSizeX, int maxSizeY, int maxBuffers, size_t maxMemory);
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</pre>
|
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<table border="1" cellpadding="2" cellspacing="2" style="text-align: left">
|
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<tbody>
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<tr>
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<th>
|
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Argument</th>
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<th>
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Description</th>
|
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</tr>
|
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<tr>
|
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<td>
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<code>portName</code></td>
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<td>
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The name of the asyn port for this detector.
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</td>
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</tr>
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<tr>
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<td>
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<code>camserverPort</code></td>
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<td>
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The name of the asyn TCP/IP port to communicate with camserver. This must have
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been previously created with <code>drvAsynIPPortConfig()</code>,
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</td>
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</tr>
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<tr>
|
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<td>
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<code>maxSizeX</code></td>
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<td>
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The number of pixels in the X direction on the detector. This is 487 for the Pilatus
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100K.</td>
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</tr>
|
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<tr>
|
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<td>
|
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<code>maxSizeY</code></td>
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<td>
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The number of pixels in the Y direction on the detector. This is 195 for the Pilatus
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100K.</td>
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</tr>
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<tr>
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|
<td>
|
|
<code>maxBuffers</code></td>
|
|
<td>
|
|
Maximum number of buffers to be created for plugin callbacks. Passed to the constructor
|
|
for the ADDriver base class.</td>
|
|
</tr>
|
|
<tr>
|
|
<td>
|
|
<code>maxMemory</code></td>
|
|
<td>
|
|
Maximum number of bytes of memory to be allocated for plugin callbacks. Passed to
|
|
the constructor for the ADDriver base class.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>
|
|
The following is an example st.cmd startup script:
|
|
</p>
|
|
<pre>< envPaths
|
|
errlogInit(20000)
|
|
|
|
dbLoadDatabase("$(AREA_DETECTOR)/dbd/pilatusDetectorApp.dbd")
|
|
pilatusDetectorApp_registerRecordDeviceDriver(pdbbase)
|
|
|
|
###
|
|
# Create the asyn port to talk to the Pilatus on port 41234.
|
|
drvAsynIPPortConfigure("camserver","gse-pilatus2:41234")
|
|
# Set the input and output terminators.
|
|
asynOctetSetInputEos("camserver", 0, "\030")
|
|
asynOctetSetOutputEos("camserver", 0, "\n")
|
|
|
|
pilatusDetectorConfig("Pil", "camserver", 487, 195, 50, 200000000)
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/ADBase.template", "P=13PIL1:,R=cam1:,PORT=Pil,ADDR=0,TIMEOUT=1")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/pilatus.template","P=13PIL1:,R=cam1:,PORT=Pil,ADDR=0,TIMEOUT=1,CAMSERVER_PORT=camserver")
|
|
|
|
# Create a standard arrays plugin
|
|
drvNDStdArraysConfigure("PilImage", 5, 0, "Pil", 0, -1)
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDPluginBase.template","P=13PIL1:,R=image1:,PORT=PilImage,ADDR=0,TIMEOUT=1,NDARRAY_PORT=Pil,NDARRAY_ADDR=0")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDStdArrays.template", "P=13PIL1:,R=image1:,PORT=PilImage,ADDR=0,TIMEOUT=1,SIZE=32,FTVL=LONG,NELEMENTS=94965")
|
|
|
|
# Create an ROI plugin with 8 ROIs
|
|
drvNDROIConfigure("PilROI", 5, 0, "Pil", 0, 8, -1)
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDPluginBase.template","P=13PIL1:,R=ROI1:, PORT=PilROI,ADDR=0,TIMEOUT=1,NDARRAY_PORT=Pil,NDARRAY_ADDR=0")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROI.template", "P=13PIL1:,R=ROI1:, PORT=PilROI,ADDR=0,TIMEOUT=1")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:0:,PORT=PilROI,ADDR=0,TIMEOUT=1,HIST_SIZE=256")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:1:,PORT=PilROI,ADDR=1,TIMEOUT=1,HIST_SIZE=256")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:2:,PORT=PilROI,ADDR=2,TIMEOUT=1,HIST_SIZE=256")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:3:,PORT=PilROI,ADDR=3,TIMEOUT=1,HIST_SIZE=256")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:4:,PORT=PilROI,ADDR=3,TIMEOUT=1,HIST_SIZE=256")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:5:,PORT=PilROI,ADDR=3,TIMEOUT=1,HIST_SIZE=256")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:6:,PORT=PilROI,ADDR=3,TIMEOUT=1,HIST_SIZE=256")
|
|
dbLoadRecords("$(AREA_DETECTOR)/ADApp/Db/NDROIN.template", "P=13PIL1:,R=ROI1:7:,PORT=PilROI,ADDR=3,TIMEOUT=1,HIST_SIZE=256")
|
|
|
|
# Create "fastSweep" drivers for the MCA record to do on-the-fly scanning of ROI data
|
|
initFastSweep("PilSweepTotal", "PilROI", 8, 2048, "TOTAL_ARRAY", "CALLBACK_PERIOD")
|
|
initFastSweep("PilSweepNet", "PilROI", 8, 2048, "NET_ARRAY", "CALLBACK_PERIOD")
|
|
|
|
# Load MCA records for the fast sweep drivers
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:0:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 0)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:1:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 1)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:2:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 2)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:3:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 3)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:4:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 4)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:5:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 5)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:6:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 6)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:7:TotalArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepTotal 7)")
|
|
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:0:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 0)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:1:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 1)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:2:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 2)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:3:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 3)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:4:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 4)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:5:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 5)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:6:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 6)")
|
|
dbLoadRecords("$(MCA)/mcaApp/Db/mca.db", "P=13PIL1:,M=ROI1:7:NetArray,DTYP=asynMCA,NCHAN=2048,INP=@asyn(PilSweepNet 7)")
|
|
|
|
|
|
#asynSetTraceMask("Pil",0,255)
|
|
#asynSetTraceMask("PilROI",0,3)
|
|
#asynSetTraceIOMask("PilROI",0,4)
|
|
|
|
# Load scan records for scanning energy threshold
|
|
dbLoadRecords("$(SSCAN)/sscanApp/Db/scan.db", "P=13PIL1:cam1:,MAXPTS1=2000,MAXPTS2=200,MAXPTS3=20,MAXPTS4=10,MAXPTSH=10")
|
|
|
|
set_requestfile_path("./")
|
|
set_savefile_path("./autosave")
|
|
set_requestfile_path("$(AREA_DETECTOR)/ADApp/Db")
|
|
set_requestfile_path("$(SSCAN)/sscanApp/Db")
|
|
set_pass0_restoreFile("auto_settings.sav")
|
|
set_pass1_restoreFile("auto_settings.sav")
|
|
save_restoreSet_status_prefix("13PIL1:")
|
|
dbLoadRecords("$(AUTOSAVE)/asApp/Db/save_restoreStatus.db", "P=13PIL1:")
|
|
|
|
iocInit()
|
|
|
|
# save things every thirty seconds
|
|
create_monitor_set("auto_settings.req", 30,"P=13PIL1:,D=cam1:")
|
|
|
|
</pre>
|
|
<br />
|
|
<h2 id="MEDM screens" style="text-align: left">MEDM screens</h2>
|
|
<p>
|
|
The following show the MEDM screens that are used to control the Pilatus debtector.
|
|
Note that the general purpose screen ADBase.adl can be used, but it exposes many
|
|
controls that are not applicable to the Pilatus.</p>
|
|
<p>
|
|
<code>pilatusDetector.adl</code> is the main screen used to control the pilatusROI
|
|
SNL program. All records except those for ROIs are accessed through this screen.
|
|
</p>
|
|
<center>
|
|
<h3 style="text-align: center">
|
|
pilatusDetector.adl</h3>
|
|
<img alt="pilatusDetector.png" src="pilatusDetector.png" /></center>
|
|
<p>
|
|
<code>NDROI8.adl</code> is used to define the ROIs, and to display the statistics
|
|
for each ROI. In this example there are 3 valid ROIs defined. ROI 0 is the entire
|
|
detector. ROI 1 is a 100x50 rectangle starting at [300,60], and ROI 2 is a
|
|
50x30 rectangle starting at [320,70]..</p>
|
|
<center>
|
|
<h3 style="text-align: center">
|
|
NDROI8.adl</h3>
|
|
<img alt="NDROI8.png" src="NDROI8.png" /></center>
|
|
<p>
|
|
<code>mca.adl</code> can be used to plot the net or total counts in an ROI when
|
|
NImages>1. In this example the plot is the net counts in ROI 1 as the diffractometer
|
|
chi was scanned +- 1 degree with 1000 points at .02 seconds/point. This was done
|
|
with the SPEC command
|
|
</p>
|
|
<pre>lup chi -1 1 1000 .02
|
|
</pre>
|
|
<p>
|
|
using trajectory scanning on a Newport kappa diffractometer. This was a compound
|
|
motor scan with the Newport XPS putting out pulses every .02 seconds. These pulses
|
|
triggered the Pilatus in External Enable mode. The Pilatus driver read each
|
|
TIFF file as it was created and updated this plot every 0.2 seconds. The total time
|
|
to collect this scan with 1000 images was 20 seconds.</p>
|
|
<h3 style="text-align: center">mca.adl</h3>
|
|
<img alt="pilatusMCA.png" src="pilatusMCA.png" style="text-align:left"/>
|
|
<p>
|
|
<code>scan_more.adl</code> is used to define a scan. In this example the sscan record
|
|
is set up to scan the ThresholdEnergy PV and to collect the total counts in ROI2,
|
|
which was defined to include the entire detector.</p>
|
|
<h3 style="text-align: center">scan_more.adl</h3>
|
|
<center><img alt="pilatusROI_scan_more.png" src="pilatus_scan_more.png"/></center>
|
|
<p>
|
|
<code>scanDetPlot.adl</code> is used to plot the results of a scan after it is complete.
|
|
In this example the total counts in ROI 2 are plotted as a function of the ThresholdEnergy
|
|
as it was scanned from 3000 to 10000 eV in 250 eV steps. The source was Fe55, and
|
|
the cut-off is at 6 keV, as expected for the Mn Ka and Mn Kb x-rays that this source
|
|
produces.</p>
|
|
<center>
|
|
<h3>
|
|
scanDetPlot.adl</h3>
|
|
<img alt="pilatus_scan_plot.png" src="pilatus_scan_plot.png" /></center>
|
|
<p>
|
|
<code>asynRecord.adl</code> is used to control the debugging information printed
|
|
by the asyn TCP/IP driver (asynTraceIODriver) and the SNL program (asynTraceIODevice).</p>
|
|
<center>
|
|
<h3>
|
|
asynRecord.adl</h3>
|
|
<img alt="pilatusAsynRecord.png" src="pilatusAsynRecord.png" /></center>
|
|
<p>
|
|
<code>asynOctet.adl</code> can be used to send any command to camserver and display
|
|
the response. It can be loaded from the More menu in asynRecord.adl above.</p>
|
|
<center>
|
|
<h3>
|
|
asynOctet.adl</h3>
|
|
<img alt="pilatusAsynOctet.png" src="pilatusAsynOctet.png" /></center>
|
|
<br />
|
|
<center>
|
|
<h2 id="SPEC interface" style="text-align: left">
|
|
SPEC interface</h2>
|
|
</center>
|
|
<p>
|
|
At the GSECARS beamlines (13-ID-C and 13-BM-C) at the APS we use SPEC to control
|
|
our Newport diffractometers. We have added and modified SPEC macros to use the pilatusDetector
|
|
areaDetector driver to treat the Pilatus detector as a SPEC counter. This works in both traditional
|
|
step-scanning mode, as well as in <a href="http://cars.uchicago.edu/software/epics/trajectoryScan.html">
|
|
trajectory scanning</a> mode. Here are some snippets from the SPEC macros for
|
|
the Pilatus. We can supply the source files on request.</p>
|
|
<pre># need some more globals (kludge)
|
|
global PILATUS_ROI_PV
|
|
global PILATUS_imgPATH_PV
|
|
global PILATUS_FNAME_PV
|
|
global PILATUS_FILENUMBER_PV
|
|
global PILATUS_FILEFORMAT_PV
|
|
global PILATUS_EXPSRTM_PV
|
|
global PILATUS_NFRAME_PV
|
|
global PILATUS_EXPPRD_PV
|
|
global PILATUS_NEXPFRM_PV
|
|
global PILATUS_ACQ_PV
|
|
global PILATUS_ACQMODE_PV
|
|
|
|
###############################################################
|
|
def _setup_img '{
|
|
local j, str
|
|
|
|
# PILATUS_PREFIX should be detector aquisition pv (GSE-PILATUS1:)
|
|
if ( PILATUS_PREFIX == "") PILATUS_PREFIX = "GSE-PILATUS1:"
|
|
PILATUS_PREFIX = getval("Enter PILATUS pv prefix",PILATUS_PREFIX)
|
|
|
|
# rois pvs
|
|
PILATUS_ROI_PV = PILATUS_PREFIX "ROI1NetCounts"
|
|
PILATUS_imgPATH_PV = PILATUS_PREFIX "FilePath"
|
|
PILATUS_FNAME_PV = PILATUS_PREFIX "Filename"
|
|
PILATUS_FILENUMBER_PV = PILATUS_PREFIX "FileNumber"
|
|
PILATUS_FILEFORMAT_PV = PILATUS_PREFIX "FileFormat"
|
|
PILATUS_EXPSRTM_PV = PILATUS_PREFIX "ExposureTime"
|
|
PILATUS_NFRAME_PV = PILATUS_PREFIX "NImages"
|
|
PILATUS_EXPPRD_PV = PILATUS_PREFIX "ExposurePeriod"
|
|
PILATUS_NEXPFRM_PV = PILATUS_PREFIX "NExposures"
|
|
PILATUS_ACQ_PV = PILATUS_PREFIX "Acquire"
|
|
PILATUS_ACQMODE_PV = PILATUS_PREFIX "AcquireMode"
|
|
...
|
|
|
|
def epics_pilatus_count '{
|
|
...
|
|
# write to data base fields
|
|
# Need to convert path from string to byte array
|
|
# Note: we use the "wait" parameter in epics_put here (new to spec5.7.02) so that
|
|
# it uses ca_put_callback, to know that all PVs have been processed
|
|
# before we start counting. Use 1 second timeout, will actually be
|
|
# much faster than this unless something is wrong.
|
|
array _temp[256]
|
|
_temp = PILATUS_IMAGE_DIR
|
|
# Do not change path for now
|
|
#epics_put(PILATUS_imgPATH_PV,_temp, 1)
|
|
epics_put(PILATUS_FNAME_PV,img_fname, 1)
|
|
epics_put(PILATUS_FILENUMBER_PV,NPTS, 1)
|
|
epics_put(PILATUS_FILEFORMAT_PV,_fileformat, 1)
|
|
epics_put(sc_prtm_pv,cnt_time_val, 1)
|
|
epics_put(PILATUS_EXPSRTM_PV,cnt_time_val, 1)
|
|
epics_put(PILATUS_ACQMODE_PV,0, 1) # Internal trigger
|
|
epics_put(PILATUS_NFRAME_PV, 1, 1)
|
|
epics_put(PILATUS_NEXPFRM_PV, 1, 1)
|
|
|
|
|
|
def user_getcounts '{
|
|
local pv_roi, j, pv
|
|
|
|
...
|
|
# using image_count routine
|
|
} else if ( EPICS_COUNT == 4 ) {
|
|
S[iroi] = 0
|
|
S[iroi] = epics_get(PILATUS_ROI_PV)
|
|
</pre>
|
|
<br />
|
|
<center>
|
|
<h2 id="Performance measurements" style="text-align: left">
|
|
</h2>
|
|
<h2 style="text-align: left">
|
|
Performance measurements</h2>
|
|
</center>
|
|
<p>
|
|
The following measurements were done to demonstrate the performance that can be
|
|
obtained with pilatusROI.</p>
|
|
<ol>
|
|
<li>AcquireMode=Internal, NImages=1000, ExposureTime=.005, ExposurePeriod=.01, NExposures=1.
|
|
The time to collect this series should be exactly 10.0 seconds. The actual time
|
|
was measured using the EPICS camonitor program. It printed the time when acquisition
|
|
was started (Acquire changed to Busy) and when acquisition was complete (Acquire
|
|
changed to Done). The time was 10.274 seconds. This includes the time for camserver
|
|
to save all 1000 images to disk (366 MB), and for pilatusROI to read each file,
|
|
correct the bad pixels and flat field, compute the ROIs, and post the ROIs to EPICS.
|
|
It also posted the images to EPICS at 1Hz (10 images total). The total additional
|
|
time was less than 0.3 seconds for all 1000 images.</li>
|
|
<li>AcquireMode=Internal, NImages=1, ExposureTime=.01, NExposures=1. An EPICS sscan
|
|
record was used to collect 1000 points. There were no positioner PVs (to eliminate
|
|
motor overhead). The only detector trigger was the pilatusROI Acquire PV. The only
|
|
detector PV was ROI1TotalCounts. In this mode camserver is being told to individually
|
|
collect each file. If there were no overhead then time to collect this series should
|
|
be exactly 10.0 seconds. The actual time measured using the EPICS camonitor program
|
|
was 49.161 seconds. The overhead is thus 39.161 seconds, or 39 ms per point. In
|
|
this single-frame mode pilatusROI is thus able to collect >20 images/second. For
|
|
comparison, another measurement was done using the same EPICS sscan record, but
|
|
using a Joerger VSC16 scaler as the detector trigger and detector. The preset time
|
|
was also .01 seconds. The elapsed time for a 1000 point scan was 16.068 seconds,
|
|
so the overhead was 6.068 seconds, or 6 ms per point.</li>
|
|
<li>AcquireMode=Ext. Enable, NImages=1000, NExposures=1. SPEC was used to collect
|
|
1000 points using <a href="http://cars.uchicago.edu/software/epics/trajectoryScan.html">
|
|
trajectory scanning</a> mode with the Newport XPS motor controller. The following
|
|
SPEC command was used:
|
|
<pre> lup chi -2 2 1000 .015
|
|
</pre>
|
|
This tells SPEC to do a relative scan of the chi axis from -2 degrees to +2 degrees
|
|
with 1000 points at .015 seconds/point. On our kappa diffractometer this entails
|
|
a coordinated motion of the phi, kappa and omega axes. The EPICS trajectory scanning
|
|
software downloads the non-linear trajectory that SPEC computes into the XPS controller,
|
|
which executes it. As the motors are moving the XPS outputs synchronization pulses
|
|
at the period of the collection time, .015 seconds in this case. These pulses are
|
|
stretched (see <a href="#Hardware notes">Hardware notes</a> below) and used as the
|
|
external input to the Pilatus. The time to execute this scan should be 15.0 seconds.
|
|
The actual time was 16.3 seconds, measured using camonitor on the Acquire PV. Again,
|
|
this includes the time for camserver to save all 1000 images to disk (366 MB), and
|
|
for pilatusROI to read each file, correct the bad pixels and flat field, compute
|
|
the ROIs, and post the ROIs to EPICS. It also posted the images to EPICS at 1Hz
|
|
(15 images total). The total additional time was less than 1.3 seconds for all 1000
|
|
images. As soon as the acquisition was complete SPEC plotted the net counts in the
|
|
first ROI (containing the Bragg peak) as follows:
|
|
<center>
|
|
<h3>
|
|
1000 point SPEC scan with 15 ms per point collected in 16.3 seconds</h3>
|
|
<img alt="pilatusROI_spec.png" src="pilatus_spec.png" /></center>
|
|
<p>
|
|
</p>
|
|
For comparison this identical scan was executed in traditional step-scanning mode,
|
|
where the motors stopped at each point in the scan. The Pilatus was run in Internal
|
|
mode with NImages=1. The total time for the scan was 870 seconds (more than 14 minutes),
|
|
compared to 16.3 seconds in trajectory mode. Most of this overhead is the settling
|
|
time for the motors, with only a small fraction due to the Pilatus single-exposure
|
|
mode. The trajectory scanning mode is thus more than 50 times faster to execute
|
|
the identical SPEC scan.</li>
|
|
</ol>
|
|
<br />
|
|
<center>
|
|
<h2 id="Hardware notes" style="text-align: left">
|
|
</h2>
|
|
<h2 style="text-align: left">
|
|
Hardware notes</h2>
|
|
</center>
|
|
<h3>
|
|
Trigger pulses</h3>
|
|
<p>
|
|
The Pilatus supports 3 types of external triggering. In External Trigger mode (the
|
|
camserver ExtTrigger command) the Pilatus uses the programmed values of ExposureTime,
|
|
ExposurePeriod, NImages and NExposures. It waits for a single external trigger,
|
|
then waits for Delay seconds and then collects the entire sequence. It is very similar
|
|
to Internal mode with NImages>1, except that it waits for a trigger to begin collecting
|
|
the sequence.</p>
|
|
<p>
|
|
In External Enable mode (the camserver ExtEnable command) the Pilatus uses the external
|
|
signal to control acquisition. Only NImages and NExposures are used, ExposureTime
|
|
and ExposurePeriod are not used. When the signal is high the detector counts, and
|
|
on the transition to low it begins its readout.</p>
|
|
<p>
|
|
In External MultiTrigger Mode (the camserver ExtMTrigger command) the Pilatus uses
|
|
the programmed ExposureTime, in addition to NImages and NExposures. Each external
|
|
trigger pulse causes the Pilatus to collect one image at the programmed exposure
|
|
time. This mode works well with a trigger source like the Newport motor controllers
|
|
or the SIS380x multichannel scaler, that put out a short trigger pulse for each
|
|
image. One only needs to take care that the time between external trigger pulses
|
|
is at least 4msec longer than the programmed exposure time, to allow time for the
|
|
detector to read out before the next trigger pulse arrives.</p>
|
|
<p>
|
|
When using the External Enable mode, we use an inexpensive analog pulse generator
|
|
to convert the trigger pulses from the MM4005 and XPS to a form suitable for External
|
|
Enable mode with the Pilatus. This is the solution we have developed that seems
|
|
to be reliable:</p>
|
|
<ul>
|
|
<li>The synchonization pulses from the Newport MM4005 or XPS controller are input
|
|
into the external next pulse (channel advance, control signal 1) input of the SIS3801
|
|
multiscaler. This is the normal configuration used for MCS counting without the
|
|
Pilatus in trajectory scanning mode.</li>
|
|
<li>The Copy In Progress (CIP) output of the SIS3801 (control signal 5) is connected
|
|
to the Trigger Input of a Tenma TGP110 10 MHz Pulse Generator. CIP will output a
|
|
pulse whenever the SIS3801 does a channel advance, either in external mode with
|
|
the motor controller pulse input, or in internal timed channel advance mode. The
|
|
TGP100 Pulse Generator is configured as follows:
|
|
<ul>
|
|
<li>Trigger Input connected to CIP output of SIS3801.</li>
|
|
<li>Triggered mode.</li>
|
|
<li>Complement output.</li>
|
|
<li>Pulse duration set with knobs to 3msec.</li>
|
|
<li>TTL Output connected to the External Input of the Pilatus.</li>
|
|
</ul>
|
|
</li>
|
|
<li>With this configuration the SIS3801 CIP output is normally at 5V, and outputs
|
|
a 0V pulse 1 microsecond long. The trailing (rising) edge of that pulse triggers
|
|
the TGP110. The TGP110 TTL output is also normally at 5V, and outputs a 0V pulse
|
|
3 milliseconds long each time the SIS3801 pulses. That output is connected to the
|
|
Pilatus External Input. In External Enable mode when Pilatus External Input is high
|
|
the Pilatus is counting. When the External Input is low the Pilatus reads out. The
|
|
readout time is set via the knobs on the pulse generator to be 3 ms, which is close
|
|
to the minimum time allowed on the Pilatus.</li>
|
|
</ul>
|
|
<p>The Tenma TGP110 seems to be currently called a Tenma 72-6860, and lists for about
|
|
$350 new at <a href="http://www.newark.com">Newark</a>.
|
|
</p>
|
|
<h3>
|
|
Detector Voltage</h3>
|
|
<p>
|
|
When we were initially testing the Pilatus in the lab, we had many errors in External
|
|
Enable mode, where it did not seem to be seeing the external pulses. camserver would
|
|
get DMA timeouts, and need to be restarted. Dectris said these were happening because
|
|
the cables on our detector are longer than normal, and the voltage drop from the
|
|
power supply to the detector was leading to marginal voltage values. They suggested
|
|
shortening the cables or increasing the supply voltage slightly. When moving the
|
|
detector to the hutch these problems initially went away. However, they then recurred,
|
|
and we fixed the problem by increasing the power supply voltage from 4.4 to 4.7
|
|
volts at the detector.</p>
|
|
<p>
|
|
Dectris has since informed me that they have increased the power supply voltage
|
|
on all new Pilatus systems, so this should no longer be an issue.</p>
|
|
<br />
|
|
<center>
|
|
<h2 id="Restrictions" style="text-align: left">
|
|
</h2>
|
|
<h2 style="text-align: left">
|
|
Restrictions</h2>
|
|
</center>
|
|
<p>
|
|
The following are some current restrictions of the pilatusROI SNL program:</p>
|
|
<ul>
|
|
<li>Limited to TIFF file format. camserver can save files in other formats, but pilatusROI
|
|
can currently only read TIFF files. Furthermore, it has a very simple TIFF reader.
|
|
It does not read the TIFF tags at all, but simply assumes that there is a 4096 byte
|
|
header, followed by the 32-bit image data. The size of the image data is controlled
|
|
by the NXPixels and NYPixels PVs, which thus must be correctly set.</li>
|
|
<li>The EPICS IOC should be run on the same computer as camserver. This is not strictly
|
|
necessary, and places a small additional load on the CPU and network on that computer.
|
|
However, we have found that TIFF files are available to be read within 10ms after
|
|
camserver says they have been written if the IOC is running on the same machine
|
|
as camserver. This is true even if the files are being saved on a remote NFS or
|
|
SMB file system. On the other hand, if the IOC and camserver are running on separate
|
|
machines, then the filesystem can wait up to 1 second after camserver says the TIFF
|
|
file has been written before the IOC can read it. This is true even if the files
|
|
are being written to the computer that the IOC is running on! This 1 second delay
|
|
is often unacceptable for fast single-exposure scans, i.e. with NImages=1.</li>
|
|
<li>pilatusROI keeps retrying to read each TIFF file until the modification date of
|
|
the TIFF file is <i>after</i> the time that the exposure command was issued. If
|
|
it did not do this check then it could be reading and displaying old files that
|
|
happen to have the same name as the current files being collected. This check requires
|
|
that the computer that is running the soft IOC must have its clock well synchronized
|
|
with the clock on the computer on which the files are being written (i.e. the computer
|
|
generating the file modification time). If the clocks are not synchronized then
|
|
the files may appear to be stale when they are not, and pilatusROI will time out.
|
|
pilatusROI actually tolerates up to 10 second clock skew betweeen the computers
|
|
but any more than this may lead to problems.</li>
|
|
<li>The Abort PV does not always work because camserver does not reliably implement
|
|
the "K" command to stop an exposure sequence. In particular with NImages>1 camserver
|
|
seems to often ignore the K command completely, even with exposure times/periods
|
|
as long as 10 seconds. With NImages=1 it does kill the exposure after a few seconds.</li>
|
|
<li>The following items are hardcoded in the SNL program. They can be changed before
|
|
compiling if necessary. Some could be changed to be EPICS PVs, so they could be
|
|
controlled at run-time, but others must be defined at compile time because of limitations
|
|
in the SNL semantics.
|
|
<ul>
|
|
<li>MAX_MESSAGE_SIZE=256 The maximum size of message to/from camserver.</li>
|
|
<li>MAX_FILENAME_LEN=256 The maximum size of a complete file name including path and
|
|
extension.</li>
|
|
<li>FILE_READ_DELAY=.01 seconds. The time between polling to see if the TIFF file
|
|
exists or if it is the expected size.</li>
|
|
<li>MAX_BAD_PIXELS=100 The maximum number of bad pixels.</li>
|
|
<li>MAX_ROIS=32 The maximum number of ROIs</li>
|
|
<li>MAX_READ_ERRORS=3 The maximum number of TIFF file read errors before the SNL gives
|
|
up and aborts acquisition.</li>
|
|
</ul>
|
|
</li>
|
|
</ul>
|
|
</body>
|
|
</html>
|