Re: Update on continuous aquisitions

Frank,

I wish that were the problem.  I'm using a single channel, single sample 
scan.  Also I added a printk to the DAQ-STC line that sets the 
continuous aquisition bit on the card.  That bit is being set.  The card 
shouldn't stop when its counter rolls over according to the manual.  I 
appreciate the ideas and hopefully we'll figure this out...

-David Carr

Frank Mori Hess wrote:

> On Saturday 03 April 2004 03:46 pm, David Carr wrote:
>
> >I switched cards today from the at-mio-16e-2 to an at-mio-16e-1.   The
> >new card exhibited a similar problem but shed a little bit more light on
> >the problem.  The new card has a 8192 sample buffer instead of the
> >previous card's 2048 sample buffer.  It only aquired for 16384 calls to
> >read(comedi_fileno(dev),(void *)data,8192) compared to the previous
> >card's 65536.  This meant to me that its not the number of calls to
> >read() that causes the problem but instead the problem occurs after
> >2^27  bytes have been transferred from the card (ie: after 2^26 samples
> >[at 2 bytes/sample]).  The scan counter on the board is only 24 bits and
> >a look at the driver code leads me to believe that the continuous
> >aquisition bit on the card is being set.  This seems not to sugguest
> >that the on-board scan counter is simply stopping the card.
>
>
> Well, if you're doing scans of 4 channels then 2^26 samples would
> correspond to the 24 bit scan counter rolling over.
>

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Received on 2004-04-04Z01:37:21