13 ID-E Beamline Software Startup Guide
Generally the programs required for users to operate the beamline are fairly robust. However, on occasion the need arises to restart some of them if they crash and become unresponsive. The programs you’ll use most on the data collection computer are:
- IDL – for running routines written in the IDL programming language. These include the MCA program to interface with the energy dispersive detectors and display XRF spectra, the ESCAN routines for collecting X-ray absorption data and we also use IDL to run macros for implementing various automated functions.
- MEDM – provides a higher level suite of GUI controls for interacting with beamline hardware components.
- SampleStage – a GUI interface to the sample stages written in python that allows you to manipulate your sample, save sample stage positions for later recall and for saving visible light images of the sample.
- XRM Fast Map – a python GUI interface for collecting X-ray fluorescence fastmaps (flyscans).
- Epics Instruments – a wxPython GUI application (using wxPython) that lets us organize EPICS PVs into instruments,manage them and then save and restore their positions.
All these routines can be launched from icons on the desktop or (in the case of IDL) from the taskbar. The image above show you the various icons for each. Note that we have different versions of IDL installed on this computer and that for now we typically run IDL version 6. Version 6 incorporates a blue and orange flag icon such as the one shown in the image above on the taskbar. We’ll discuss each program below in more detail.
The SampleStage GUI application can simply be started by double-clicking on its desktop icon (the microscope). On startup it will ask you to select the current user directory for your run.
The application provides controls for moving the Coarse Stages that are the motors used for moving your sample, the Fine Stages that are generally utilized for fast-mapping, and the theta rotation stage that may be incorporated in the motor stack for some experiments. The Fine Stage and Theta controls can be hidden from view by selecting the black triangle to the left of the label. Each motor (X and Y for left-right and up-down motion, Z for focus – towards and away from the optical microscope viewing the sample) will show the current readback value (in mm’s for the fine and coarse X, Y, Z) of the stage to the immediate right of the label. The entry field to the right of the readback value allows the operator to enter an absolute position to which to move that stage (input a value and hit Enter).
Each set of motors also provides a dropdown list of predefined increments in which each motor can be stepped. Select the desired increment (again in mm’s) and then click on the blue arrows to move the stage in that direction relative to the viewing direction of the optical image. For the focus Z stage, the right arrow increases the distance from the optical microscope (stage moves further away) and the left arrow decreases the distance (moving the sample towards the objective).
X-ray Absorption Fine Structure (XAFS)