Thanks to Alexis's Analogy development, digital I/O is possible with Xenomai 
using National Instrument DAQs. While the basic DIO functionality works in the 
most current xenomai-head, I am  wondering how to achieve maximal I/O speed 
with the 32 bit digital I/O sub-device on my NI6259 card. 

The options are

1) single acquisition with a4l_sync_dio()
2) instructions and instruction lists using a4l_snd_insnlist() and 
a4l_snd_insn()
3) streaming acquisition with commands (e.g., a4l_snd_command() and related 
functions)

My question concerns how many 32-bit DIO instructions per second I
should be able to achieve with the various options.

For instance, option 1) seems to take about 5000 nanoseconds on my
Ubuntu 8 core i386 computer (3Ghz processors).
Is this normal? Or should it be faster?

Option 2) seems to give me about 50% speed up, i.e., roughly 3500
nanoseconds per DIO.

Would option 3) give me a massive speed up and get me closer to the
20Mhz processing power of the NI 6259 board? I have some problems with 
implementing commands on my NI6259 so far.

Thanks a lot for any help!

-Stefan

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