Re: Cmd/mmap with realtime

Hello Daniel,

On Thu, Nov 07, 2002 at 06:02:48PM +0100, Daniel Koch wrote:

> ... Without realtime I get I/O errors after some time even if I
> increase the read_buffer_size. I'd appreciate any help,

What CPU board do you use?

When I started with the PC104-DAS16JR on an Advantech PCM-3350 with
the NS Geode and its I/O companion I also had problems. This was
caused by ISA DMA not properly working at terminal count.

Frank helped me a lot and I finally got the combo working not using TC
to finish a transfer but a timer running at about fsample/1000 (see
the sources) to transfer the dat using DMA w/o TC. I'm now running up
to 160kHz on one or more channels w/o any error and w/o using an RTOS
layer. I had to increase the buffer size though.

Roman

-- 
Roman Fietze                                fietze_at_s.netic.de
My public key is on   http://www.s.netic.de/fietze/index.html