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what is the bottleneck (error 200279)

I have been having this problem recently since the IT department decided to "upgrade" my computer from a 2.8 Ghz to a dual 550Mhz (against my recomendationsSmiley Mad).  I am running the m series card pci6221 acquiring 7 analog and 1 encoder.  The VI will progressively fill up the buffer no matter what i do,  change buffer size, read all avail, read more often etc.  However if I exclude the encoder the VI will run a maximum of 2000 hz.  If this error is produced after the adc conversion, then the PCI bus seems like the culprit but i do not believe it.  My processor, even though a dinosoar, is not taxed 6-10%, i also have 1Gb ram.  How can this be? 
 
Windows XP, Latest nidaq, sc2345 carrier
 
Personally i believe the dinosoar computer to be the problem, but i need evidence.  And if i have 2 or 3 DMA channels, why would the encoder have any effect since it would go through a seperate conversion on the daq card independant of analog.
 
 
 
BTW i did read previous boards and did not see an answer that suited me.  my application is a state machine when left alone just reads data and in this state it still hangs up.
 
I appreciate any help or tips on the subject.
 
Chris
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Chris,

Have you tried finding out the number of available samples per channel? From here you can try setting the number of samples per channel according to that statistic.

Abhinav T.
Applications Engineer
National Instruments

 
Abhinav T.
Applications Engineering
National Instruments India

LabVIEW Introduction Course - Six Hours
Getting Started with NI-DAQmx
Measurement Fundamentals
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Abhinav Thank you for the reply.
Yes, the available samples per channel never stops increasing.  I have even tried to set the #of samples equal to the sampling rate at various rates (500Hz-1000Hz) which would mean the read function will not be called until it has received the number of samples (1 second).  Good for the processor bad for a program.  I timed the program at 312ms which i thought was slow, but it would also mean that i should be able to run the program at around 1000 Hz and 300 samples.  Also I thought that when the buffer was filling up that it was because the computer cannot catch up to the acquisition.  But this implies that I would see the processor begging for mercy which it is not, according to the task manager.  Maybe my understanding is wrong- please tell me if it is. 
I wish i had the VI analyser add on.  Not that it would help me but I would feel better.Smiley Very Happy
 
Could a processor in a dual system be "hurting" or "running on E" and not show it.  Could it be an SCC carrier limitation or a DAQ Limitation.  I do not know about the carrier, but the DAQ is the one doing its job filling up the buffer right? GOT to be a processor.  What else does that leave me with, Buss speed.  Maybe video card issues.  Follow me on this for a second.  Maybe the screen update with the graph is too much for the video to process through.  Now i have no idea how video works with no card, but i thought it was feed video ram on the motherboard and processed by a separate chip on the board, in which case the task manager would not detect a processor lag because it is lagging on video????  Man do I sound madd or what. Funny farm here I come!
 
Chris
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Chris.

You can use this document to understand the data transfer a little better.

Hope this helps

Abhinav

 
Abhinav T.
Applications Engineering
National Instruments India

LabVIEW Introduction Course - Six Hours
Getting Started with NI-DAQmx
Measurement Fundamentals
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