Digital waveform output

hello everybody
first of all: i'm working with m-series card pci 6259 and measurement studio c++.
i want to output digital waveforms to sixteen digital outputs.
the waveform buffer should contain at least 720 points.
the frequency at which the output should be changed is varying between 24kHz and 120kHz.
when one waveform buffer is done, it must be recalculated, frequency adjusted and output again, and so on...
in the data sheet of my card i read about waveform characteristics of port 0. but i can't find any
documentation about this anywhere.
so can anyone help me with this problem?
regards
markus

The standard installation of NI-DAQmx puts an item into the Start menu: Start->National Instruments->NI-DAQ->NI-DAQmx C Reference Help.
Look under C Functions->Channel Configuration/Creation->Create Digital Output Channels, and Write Functions, various DAQmxWriteDigital... functions.
Look in the NI-DAQmx Concepts section for various kinds of information about digital output.
Look for the C-language examples under Program Files\National Instruments\NI-DAQ\Examples\DAQmx ANSI C\.
John Weeks
WaveMetrics, Inc.
Phone (503) 620-3001
Fax (503) 620-6754
www.wavemetrics.com

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Attachments:
digital pulse out.vi ‏32 KB

Hi
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Don't be afraid to rate a good answer...
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Convert digital waveform to array

Hello,
I posted a problem before Christmas regarding data acquisition and accessing the hardware buffer on a 6562 card. I managed to figure out that problem but now I'm stuck when I try manipulating the data I obtain. (The original problem can be seen here: http://forums.ni.com/ni/board/message?board.id=70&thread.id=7926)
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Sorry for the long post but I feel that I needed to fully explain the problem. I'm attaching my LabView code.
Thank you for reading,
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PS. GenAcq2.vi is my code. Waveform_GenAcq2_Cfg.hws is sent by the first Generation VI; Waveform_GenAcq2_shorter_frame_indicators.hws by the second Generation VI.
Attachments:
CodeAndWaveforms.zip ‏126 KB
GenAcq_Screenshot.JPG ‏83 KB

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can be correctly read into Matlab using the following commands:
fid = fopen('c:\temp\digData.bin','r');
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Message Edited by smercurio_fc on 01-18-2008 05:26 PM
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Message Edited by Troy K on 03-23-2008 11:37 AM
Troy
CLDEach snowflake in an avalanche pleads not guilty. - Stanislaw J. Lec
I haven't failed, I've found 10,000 ways that don't work - Thomas Edison
Beware of the man who won't be bothered with details. - William Feather
The greatest of faults is to be conscious of none. - Thomas Carlyle
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Hi,
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Attachments:
data.txt ‏1 KB
test.vi ‏64 KB

When one looks at the specifications for the USB6501, one notes that it cannot do hardware-timed output. Therefore, you can't use a waveform datatype to generate output with this card.
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- David
(posted by Christian on behalf of David)

Hi JeyZ - In the past, I've worked with microprocessor-based slave devices that have nondeterministic response times to a given query from the master. For example, I would send a data query in the first byte, then expect to clock out the data from the slave in the next byte. If the slave device wasn't done with its search/retrieve routine, it had no data in the output register so all I clocked in was x"00". Could something like this be happening to you? Do you have a datasheet for the slave device you're communicating with that you can link publicly? You may also try using the SDW library to build the waveform. It will guarantee that timing parameters for the bus are met and all edges in the waveform conform to protocol requirements. Alternatively, I can only ask that you post more information about your application software and the device you're communicating with, so we can help you debug it. In response to your question about using the 6229 for I2C, that device does not have a per-cycle tristate feature. At present, only the 655x devices support that capability. Without it, you would have to do a lot of work to get this device communicating over I2C, and I can't guarantee it'll be possible in the end.

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Attachments:
digital waveform.jpg ‏49 KB

Hi tintin
Thanks for posting, and sorry you've not heard from anybody for a while.
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Kind Regards
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