Low update rate with ftdi

Hi, recently my company changed I/O communication of a custom ADC board from RS232 to usb using FTDI245R chip. Using ftd2xx.dll I obtain lower update rate of the measurements ~60-100ms instead of 20ms (rs232). Anyone noticed something like this, how did you fix it? I just used the drivers provided by FTDI: open device (once), reset device (once), flush TX, write bytes, queu status, read bytes.
Thank you

U r right.IT is really frustrating.I found out the hard way.Finally when i used BCP for serial communication the updation was much faster and i was able to curtail the data loss.Using the d2xx function.Initialize purge and do everything once and i mean it only once.Put the read buffer in a while loop and dont give the number of bytes to read from the output of transmitt buffer as suggested.Instead define your own number of nits to read.obviuosly the buffer status will be checked once and then the while loop will start executing and ur updation will be fast.I am doing the samething.

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Attachments:
Hybrid DAQ_10.vi ‏73 KB

Hi Rocket 154,
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New Discussions ReponsesThe new system for discussions asks that after you mark your question as Solved. You should take the time to mark any posts that have aided you with the tag and the post that provided your answer with the tag. This not only gives points to the posters, but points anyone searching for answers to similar problems to the proper posts.
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This account is no longer active. Contact ShadesOfGray for current posts and information.

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Attachments:
frequencytest.vi ‏21 KB

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