Contributions:TMSiADC

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Synopsis

A source component interfacing to TMS Refa and Porti systems (also BrainProducts' QuickAmp series).

Location

http://www.bci2000.org/svn/trunk/src/contrib/SignalSource/TMSi

Versioning

Author

M.M.Span, Copyright: (C) RUG University of Groningen

Jeremy Hill and Christian Puzicha: Max Planck Institute for Biological Cybernetics, Tübingen

Version History

  • V0.01 - 12/10/2005 - First start
  • V0.02 - 27/10/2005 - Primary working version: entered testing phase
  • V0.03 - 25/01/2006 - Multiple devices (PORTI) useable Synchronizing PORTIs work in progress
  • V0.04 - 03/04/2006 - Porti Synchro disbanded. Working on selecting channels
  • V0.05 - 15/05/2006 - Using the features pull out unused channels from the common reference pool
  • Revision 1.1 2006/07/04 18:45:50 mellinger - Put files into CVS.
  • Revision 1.2 2006/07/05 15:20:10 mellinger - Minor formatting and naming changes; removed unneeded data members.
  • Revision 2.0 2009/10/25 jhill
    • Allow selection of a subset of physical channels to acquire.
    • Support impedance measurement and acquisition of digital channel values.
    • Various OptionalParameters for tweaking performance.
    • Crash fixes.

Source Code Revisions

  • Initial development: <1139
  • Tested under: 2581 (using 136-channel QuickAmp)
  • Known to compile under: 2581
  • Broken since: --

Parameters

PhysicalChannels

List of 1-based physical channel indices, as configured in the amplifier's GUI. On our 136-channel QuickAmp, channel N+1 (i.e. 137) seemed to encode the digital signal (parallel-port markers): if such a channel seems to be present, it is addressable like this and is decoded.

Optional Parameters (command-line options to TMSi.exe)

TMSiBufferSizeInSampleBlocks

OptionalParameter, default value 4. Command-line option used to change the ring-buffer size. Value must divide into 100, so legal values are 1,2,4,5,10,20,25,50,100. Larger values reduce the likelihood of a buffer overflow when the CPU is stressed (now a fatal error since it leads to an actual loss of signal data) at the cost of allowing signal acquisition to be "lumpier" in time.

TMSiProcessPriority

OptionalParameter, default value 0. Legal values are 3,2,1,0,-1,-2. This command-line option changes the Windows process priority of the source acquisition module, relative to 0=normal.

TMSiSleepMsec

OptionalParameter, default value 1. Calling with --TMSiSleepMsec=0 will inhibit Sleep()ing while waiting for a sample block to come in from the amp (this used to be the default behaviour in revisions < 2.0, but caused the CPU to saturate).

TMSiAutoReference

OptionalParameter, default value 1. This boolean command-line option determines whether the amp's automatic reference mode is used.

TMSiCheckImpedance

OptionalParameter, default value 0. This boolean command-line option can be set to 1 to go into impedance-checking mode. For the QuickAmp, you should set SamplingRate to 8Hz and SampleBlockSize to something like 8. The estimated impedance in kOhm is delivered directly in this mode.

States

None.

See also

User Reference:Filters, Contributions:ADCs