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About Labview tool kit for Ti's DSP (RTDX buffer size)

 Now I am using Labview tool kit for Ti's DSP to
do the RTDX communication between Labview and Ti's 6713DSK. Now I am
encounting a problem that the my Human interface (Labview) works fine in
the first 10 minutes. However after that data looks freeze. The RTDX
become very slow. It's hard to input data or receive data to DSP through
Labview. I am sending 1 Integer 16 bit data and 1 floating data to DSP
using RTDCXwrite vi and the frequency is 33.3Hz. And at the same time I am
transfer 5 integer 16 bit data from DSP to Labview. The frequency is 25Hz.
What's wrong with this? Is that because the buffer for RTDX has been used
up? And how to set up the RTDX buffer in Labview? because I check the vi
about RTDX and can't find a definition about the buffer. This is very
important in my project. Please tell me how to set up the buffer size and
the RTDX work state (continuous mode or discontinuous). Thank you very
much and I am looking forward to hearing from you.

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Message 1 of 6
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You should post your code. Generally, you can get away with really big and fast periodic data transfers in LabVIEW if you draw it the correct way. Additionally, these tend to be situations where you need a lot of RAM in your computer, so if you have 256MB and are running W2000, it's not going to cut the mustard. To get anywhere with this type of question you need to post OS, RAM, LV version and the code, if possible.
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Message 2 of 6
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Now I am using winxp, 512Mb RAM, LV version is 7.1. My labview coding and DSP code main function is attached below. Please help me out. I want  to transfer 8 16bit integer data. Is it better that I used an array to group these data then transfer this array using only one channel. Compared with using 8 independent channels to transfer them.
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Message 3 of 6
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Now I can only supply a debugging suggestion. Make a copy of the VI. Delete the three charts and the cluster bundlers and monitor the values of A B an C with numeric indicators. Then, see how long the program lasts.
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Message 4 of 6
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So you think it's because the waveform chart consume too much memory right? How about I create a array like vdc[3]. Using this array to group the A, B, C data. Then only use 1 RTDXread to transfer data from DSP to labview. Compare with my old way,used 3 channels, Is this will make it better?
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Message 5 of 6
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I suspect that the program lasts for 10 minutes and then slows down because the charts are 10 minutes long. Once the charts start scrolling, a lot of cpu time is directed towards redrawing the graph. If you make an array of vdc[3] and return that in one communication that will be better, as well as plotting all three variables on one chart.
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Message 6 of 6
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