From: peterson_at_d...
Date: 2001-05-21 18:17:16
--- In buildcheapeeg_at_yahoogroups.com, "Joerg Hansmann" <info_at_jhansmann.de> wrote:
> Hi,
>
> ----- Original Message -----
> From: Waldemar Neto <wpneto_at_o...>
> To: <buildcheapeeg_at_yahoogroups.com>
> Sent: Sunday, May 20, 2001 5:56 PM
> Subject: Re: [buildcheapeeg] Re: Sound Card-Phase II, real-time
analysis
>
>
>
> >Hi Joerg,
> >
> > 3.9 ms is a very good delay and the interpolation idea too.
> >
> >Maybe be fine to do a simple test for real time on pragmatic
effects
> > on RS232 processing ( with any device feeding data - eg.
calculator
> > sending a senoidal function ) putting a short routine to see and
> > watching the performance. If you already did it ( or saw it )
then there's
> > no problem;
> >
> > otherwise, the practical effects may bring surprises
> > (especially for Windows' "misjudgement bandwidth ")
>
> Under Windows I would not guarantee for anything.
> So if you have something very timecritical like generating
> stimuli for evoked potential measurements I would recommend
> to put this part into the AT90S4433 software.
>
>
> >One more thing: joining with the cheap eeg idea , would it be
good to
> > allow using DOS too ( for retrieve old PCs XT up to 486 ) ? Just
> > wondering that it could amplify the beneficts of the project .
>
> Under DOS it is easy to get well defined response times.
>
> Regards,
>
> Joerg
Just a couple of comments from your technologically challenged
colleague: Lexicor still runs everything under DOS just because of
the timing problems, I think. And their machines are getting harder
and harder to set up on newer Win 98 machines and up. Hard to get
Windows to really let go and give you a fully functioning version of
DOS. But a few years ago a company called Aquathought put out a 16-
channel machine that was adequate for doing QEEG, and it ran under
Windows 95. That machine only cost $2500 or so (in contrast to
Lexicor's $6 or 7 K for their big machines) and really impressed a
lot of us when we saw it, but it has now apparently disappeared from
the market--I don't know exactly why it died, but there was only the
brainmapping software for it, no training software, and maybe that's
why it didn't last. I think they were encouraging people to write
open-source SW for it too.
Regards
Jim
This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:30 BST