Re: FIFO buffer overflow for ni_pcimio

Thank you for your reply.
I was under the impression that read() reads from somewhere in the pc
memory that cmd DMA transfers data to.
Does read() read directly from FIFO via DMA transfer?
will the read() error caused by FIFO buffer overflow be an I/O error?

Thanks again,

Naoko



Quoting Frank Mori Hess <fmhess_at_users.sourceforge.net>:

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> On Thursday 05 February 2004 02:50 pm, Naoko Kurahashi wrote:
> > Hi,
> > When using the ni_pcimio driver, and using asyncronous streaming
> > acquisition, how does the card tell us that the onboard FIFO buffer is
> > overfull? I believe this has something to do with callback and
> > COMEDI_CB_OVERFLOW in the comedi_async structure.
> 
> You'll get an error when you try to read() the data.
> 
> - -- 
> Frank
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Received on 2004-02-09Z01:28:02