Reading in data from a new CTF system with ECC

Michael Wibral wibral at MPIH-FRANKFURT.MPG.DE
Wed Nov 29 15:11:17 CET 2006


I'm trying to read in data from a CTF 275 channel system. It is equipped
with the new ECC console that now (among other things) is responsible
for the triggers from presentation. These 'triggers' are written to the
channel UPPT001 (indicating that they arrive on the first parallel port
of the Acq computer?).
We record in a 'pseudo trial'ed fashion i.e. one trigger starts the
acquistion of one long trial, other triggers are written to the UPPT001
channel but do not chop the data. There is also a truly continous
recording resulting in an ...aux.ds file but that's still experimental
CTF said.

When I use trialfun_ctf_continuous to read in the data no triggers are
found and as a consequence no trials are defined - I wonder whether
there is a problem with things like the 'STIM' channel and the
[backpanel, frontpanel] stuff as the machine doesn't seem to have any
back or frontpanel - but the ECC instead.

I have also tried to trial the data inside the CTF Software (using newDs
with the corresponding markers) and then to use trialfun_ctf_epoched
with the same result.

BESA reads the triggers however without problems, both, their values
(1,2,3...) and der names. so I think the data format shouldn't have
changed too much.

here is the code (with variations) that I have tried so far - any

% Reading CTF .ds data files and preprocess them
clear all;

pathname ='/home/wibral/DATA/BAM_EEGIIIRC_oldTime/';
% I used either continuous  or epoched data
% filename='ASL30_AMMEGIIIRC_20061124_01_trials.ds';

% build analysis configuration
cfg=[];{'MEG' 'UPPT001'}; % also tried 'STIM' instead
cfg.trialfun='trialfun_ctf_continuous'; % also tried ..._epoched

% I tried either of the following three lines
cfg.trialdef.stim = 2;
cfg.trialdef.includeTrigger= 2;
% I also tried strings given in the markers file instead...

% this doesn't result in any output either...interestingly


% I also tried to give a trigger file separately:
% cfg.trialdef.trgfile= strcat(FullName,'/','MarkerFile.mrk');


cfg.blcwindow=[-0.2 0];


Any help is appreciated. Thank you very much.

Best Regards,
Michael Wibral

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