You are here: GXSM: The complete open source SPM control solution

The GXSM is the Gnome X Scanning Microscopy project, it is a bit more than just a piece of software (the GXSM itself), there is full hardware support for DSP based SPM controller including open source DSP software and a growing set of SPM related electronics. And it is not limited to SPM at all, it provides generic multidimensional image and data movie processing.

This is the official web site of the GXSM. It contains information about downloading, installing, using, and enhancing it. We try to provide as much information about the GXSM community and related projects as possible. Hopefully you will find what you need here, and if not feel free to ask for online support. In spirit of The GIMP: Grab a properly chilled beverage and enjoy.

The GXSM software is a powerful graphical interface for any kind of 2D and up to 4D (timed and multilayered 2D mode) data acquisition methods, but especially designed for SPM and SPA-LEED, which are used in surface science. It includes methods for 2D data (of various types: byte, short, long, double) visualization and manipulation. It can be used for STM, AFM, SNOM, SPA-LEED, but is by far not limited to those! Especially in standalone mode it can perform many SPM typical image manipulations and analysis tasks. Latest additions enables full support of handling and on-the-fly viewing image sequences and arbitrary profiling in 4 dimensions.

Please visit our hardware partner SoftdB and look for Scanning Probe Microscopy Products.

The GXSM project is a complete open source software solution for

  • all SPM needs: STM, AFM, SNOM, SARLS... (and SPA-LEED**), new: PAC/PLL for direct tuning fork/qPlus (TM) sensor support.
  • complete SPM hardware: offering leading Digital Signal Processing (DSP+FPGA+Analog-IO) technology (real time multitask statemachine) for feedback, scanning, vector probing and multi channel data acquisition.
  • close but independent collaboration with a small Canadian company SoftdB, see SPM products making dedicated SPM hardware available worldwide to our open source SPM / GXSM community!
  • GXSM core independent Plug-in hardware interface "HwI" allows to add support for any hardware without touching the GXSM core.
  • 2d..4-dimensional data acquisition and visualization: Profile, Image and 3D and Volume rendering data views (gaming level speed 3D real time visualizations via GPU rendering using GL 3.4 and above, GL capable hardware is required for 3D rendering.) -- can be exported in vector (pdf, svg) format for later editing (using Cairo technology), publication quality!
  • On-the-fly, i.e. while scanning, Vector-Probe (any kind of spectroscopy or manipulation), automatic gridded probing.
  • Event management: User triggered events like bias change, probe, etc. are attached by coordinate and time to the scan data.
  • 2d, 3d or 4-dimensional image data processing, timed and layered data handling.
  • Plug-in interface for data processing, machine control and GXSM core independent hardware support and any kind of user extensions.
  • Im-/Export plug-ins for many commercial SPM software (and some other) data formats.
  • Python script language interface and console for advanced automatizing.
  • New: On hot-key press script execution from scan window. Example: adjust conditions for manipulation, etc. Or even trigger any probe/sts/.. action. ALso now optional automatic pre-probe script execution to set initial conditions. Action scripts are predefined and simply editable via the python console.

GXSM major milestone news feed

... 2016/2017 Update - The all new GUI for Gxsm-3.0 (V3.42.0 "Red-Force-One" and up) is finally here! Latest: GXSM 3.0 V3.46.0 "Action Eclipse"

  • all new Gtk-3.0 (gtk 3.22 and later) GUI. Much more new beyond the modern new look and new control/icon scheme, from a total overhaul of GUI functionalities enforced by the new gtk3 generation, new background rendering, new cairo graphics,..:
  • now using dconf for dynamic and life user parameter storage and retrieval. Make use of latest glib technology using highly optimized data GVariant data structures.
  • support for MK2 and MK3-PLL-A810 based hardware. All new HwI GUI and still progressing. At this time 100% compatible with previous gxsm DSP code, can use either version and "hot" switch!
  • all new graphics, image and profile, etc. -view rendering via the Cairo backend. PNG/SVG/PDF output vector graphics rendering of scan views and profiles (Save->Image/Drawing).
  • the new glib/gdk/gtk V3.x brings on a long waited for solid solution for thread save background (idle task) rendering what was a pain with gtk2 and a troublesome known issue more or less depending on the system architecture. No more any issue here!
  • updated GUI and overhauled python console. Attention: some have changed!
  • new DSP Control GUI simplification mode in "non-config" state hiding non frequently used settings with a simple click.
  • currently after several month of intense beta-testing at laboratory conditions and production use we have decided to release this new version. Operating a Createc Low-Temperature STM and AFM at 5K. Demonstarted excellent sub molecular resolution in force mapping mode (Tuning-Fork) using the MK3-A810-PLL.
  • OpenGL 3D view is now again fully functional! It requires at minimum OpenGL-4.0 hardware capabilities and is about to unleash the full GPU power for shading. New features under development: 3D scan view with live tip modeling. 3D terrain like surface rendering, for multi-dimendional data (image stack in value dimension): slicing and volumetric rendering.
Image on left: Sample NC-AFM data (frequency shift) of custom designed precursors molecules which were surface synthesized into GNR assemblies. Data aquired using GXSM-3.0 + SR-MK3-A810/PLL operating a modified CREATEC based LT-STM/AFM in force detection mode, constant height operation at approx. 70pm oscillation amplitude using a Q-Plus (TM Franz J. Giessibl) Sensor @29.84kHz and a "magic" functionalized tip not to be disclosed here. In green shades overlayed: Simple Mechanical Probe Paricle Simulation(*) -- showing a near perfect match.
Hover the pointer over the image to reveal raw data.
(*) Simulation provided via the Gxsm-3 AFM-Mechnical-Simulation Plug-In module.

... 2014 Update - MK3-PLL "Signal Master":

  • While the robust Model-MK2-A810 is still main stream the more powerful "SignalRanger Mark 3" (Model MK3-PLL) is maturing with new powerful features. Now for a while in day by day lab operation and data production.
  • New: Digital hot-pluggable signals: Total configuration freedom of real time digital signal processing modules, in- and outputs, complex signal mixing capabilities and more.
  • All new python support utility classes and powerful life signal monitoring, scope views, meters to visualize signals and more. Also new PLL tuning utilities included.
  • The SoftdB provided and GXSM dedicated high precision high voltage amplifier "Smart Piezo Drive" is now fully digitally communicating with Gxsm and SPM-DSP via a USB link. No external analog connection any more required for offset, freeing up outputs of the SPM controller! Smooth glitch free gain and filter adjustments, digital monitoring of the actual HV outputs and more!
  • The GXSM team was present at ICN+T 2014 in Vail, CO -- please review our poster here on right.

... 2012 Looking into a Bright Future for the Project - beginning of Model MK3-PLL support:

  • The more powerful "SignalRanger Mark 3" (Model MK3-PLL) what includes the same (but for the PLL with a highly stabilized reference frequency) well established and lab proven "Analog-810" (SR2-A810-V2) (by SoftdB) was evaluated and DSP code porting is finished.
  • Together with a frequency stabilized A810 version this MK3 based system allows running a novel digital PLL algorithm, very suitable for tuning fork/qPlus (TM) sensor based AFM systems -- a standaloone MK3 based PLL is now availabel via SoftdB, see SMP products.
  • Also is the SoftdB team is now providing a standalone but GXSM dedicated high precision high voltage amplifier "Smart Piezo Drive"!
  • The GXSM team was present at NC-AFM 2011 in Lindau with this poster you can review here on right.

New (introduced in 2009, and still up-to-date) and SPM dedicated Analog-IO: the SR2-A810 is ready for GXSM!

  • Full support of the "SignalRanger Mark 2 (Model MK2-A810) with Analog-810" (SR-A810-V2) (designed by SoftdB with input of the GXSM SPM team) by GXSM -- real world laboratory tested!
  • Linux kernel module and DSP software support via the related SRanger projekt.
  • Complete GXSM functionvaility known by the previous SRanger is available, just at higher performance.
  • The new SR2-A810 is available here, also SPM-Lab-ready "SPM Open Source Controller: Model MK2-A810" for plug-in for your 19 rack: Check it out here at Soft-dB.
  • In brief: USB-2.0, 300MHz DSP, Spartan FPGA + SPM dedicated 8x in and 8x out 16-bit analog at up to 150kHz and digital IO module including a two channel counter functionality (Specsheet and SR2_Analog_810_UsersManual.pdf)
  • DSP real time data pre and post processing: signal recovery and resolution beyond the native 16bit on all input channels only depending on current bandwidth or scan speed via automatic and real time resolution adjustement only limited by statistical noise. At typically conditions you can get up to 22bits. All XYZ scan and Offset outputs are DSP level resolution enhanced via a special algorithm and archive full 19bits at effective 20kHz bandwidth for scan signals -- however, the loop delay is not affected as sampling in/out is alwasy at 150kHz.
  • All DSP level scan signal calculations, vector transformations, etc. are at 32bit resolution (fixed point and fractional calculus).

2ML Ge on Si 100, filled states, U=-2V, I=1nA An example: The STM Image at the left shows an atomically resolved surface of a with about 2 Monolayers of Germanium covered Silicon 100 crystal surface. Brighter means the "atoms" are at a higher layer. The structure made of overlapping "balls" looking like a mesh represents the local density of states -- or just density of the electrons seen by the STM tip at the surface. The maxima can be interpreted as the positions of the atoms of the top layer...

GXSM is powerful, it is easy to extend via plug-ins, it is unlimited in data size and it is a free and open source software hosted by SourceForge! The recent version (Gxsm-2.0 CVS branch) is based on the Linux (i386 and ppc) Gtk+/Gnome-2 development environment. But it is a multi-platform system and is running on Darwin/Mac OS X + Fink (minimal requirements are gtk2/gnome2.6) systems as well.

About GXSM

The GXSM program and project is originated at the Institut für Festkörperphysik (Solid State Physics) University of Hannover, Germany and is currently maintained by then GXSM developers team, click here to view institutes using GXSM.

GXSM is licensed under the terms of the GNU General Public License (GPL).

We appreciate any help and sponsoring this non profit project.
Thanks, the GXSM Team.

Please cite this article if you are using GXSM

Publications about GXSM can be found in Review of Scientific Instruments, Journal of Vacuum Science and Imaging & Microscopy. Please cite a paper in all your publications that contain data acquired or images analyzed or created using GXSM:

And please also let the GXSM community know about your publications/presentations, including any GXSM acquired or treatet data! Please cite us, thank you.

** SPA-LEED: historical support. Latest hardware is even more dedicated with dual high speed counter support, but software plugins currently are not main stream optimized for SPA-LEED control, however, it is capable to do so.

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