channel sequence problem with NI-6251

Hello!

I'm using comedi with Linux 2.4.32 and RTAI to access a NI-6251 card.

So far it is working very well, so thank you very much for your work
on comedi!

Recently I noticed a strange thing with the 6251 card: It seems that
I can only configure the sequence of channels for an AI operation
with increasing channel indices. I tested these scan sequences to work
(each row a separate scan sequence):

   0
   0,1
   0,1,2
   0,1,1,2

They behave as expected. However, the sequence 1,0 gives the values of
channels 1,1,1,1,... instead of 1,0,1,0,...

Likewise 0,2,1 yields 0,2,2,2,2,2,...

It seems the card can only switch the channel index down when a new scan
is started. This is very strange.

Are you aware of any such problem or a solution?

(Note: I could not test with comedi CVS, as it does no longer compile
with a 2.4.32 kernel, and I am locked to this kernel. I looked at
a diff to current CVS, and it seems that at least in the channel list
setup code in ni_mio_common.c nothing has changed significantly.)

I'm using a CVS checkout of comedi with version number 0.7.73.

Cheers,
-Edwin

Received on 2007-02-20Z18:23:52