Record measurements

[aleks]

Hi

System Configuration: NI cRIO-9014, chassis NI 9104, module NI c9205.

How best record to the USB mass-storage parameters measured.

Sampling parameters of 1 kHz.

1) Use the Time Loop period = 1 ms for data from the FPGA, and in each cycle to record measurements on the USB mass-storage devices.

2) Use 2 cycle. A deterministic to retrieve data from the FPGA, then measure put into the buffer FIFO.

The second cycle is not deterministic for disassembly FIFO, combining the measurement data in the data blocks for recording on USB mass-storage devices.

Thanks.

[Mellroth]

Hi aleks,

I would go for the second solution.

If you are streaming a lot of data and want that to be deterministic, you might also want to consider to write data to disk in chunks where the size is an multiple of the block size used by the hard drive. The reason is that LabVIEW RT does not cache data, so if you are not writing complete blocks, it first has to read data to be able to write to a block on disk.

/J

[aleks]

Thanks JFM

If  use the USB mass-storage with FAT32, then make an optimum buffering measurements to the size of 16 KB or more, and only then this block of data recording.

Or for OS VxWokrs is the best way to record?

Thanks.