Hey Bhoomi,
In the NI 6533/6534 for NI-DAQmx Help it states the following regarding Preloading Memory (NI 6534 Only):
"For buffered output, the NI 6534 preloads the onboard memory with data before starting the operation. Preloading eliminates or reduces the impact of the PCI bus bandwidth limitations and increases the overall transfer rate. However, preloading causes a small delay between the start command in software and the actual start of data transfer."
So really the preloading of data into memory is mostly used for Generation. But I think what you are asking is about how the acquisition session works. Well the data does get acquired into onboard memory before it gets transferred to computer memory, but the DAQmx driver does this for you. You can check out a more detailed description of how this acquisition operates in one of your other posts here. So you can wait as long as you want to get the acquired data off of the onboard memory, but if you are acquiring more data than can fit into the onboard memory, you will want to fetch it off of the onboard memory as soon as possible and as fast as possible so that you don't overflow the available memory. This can be seen with one of the Continuous Acquisition example programs, like the Continuous Read Dig Chan-Int Clk.VI. But check out my other post linked above for more info about waiting until you are ready to get the data off of the onboard memory. Is there any reason as to why you would not want to right away read the data that was read into the onboard memory?
I hope this, and the info I gave in your other post, helps. Please let us know if you have any further questions/concerns. Thanks, and have a great day.
Regards,
DJ L.
