Design Advice

[GVW007]

I am designing a higher speed acquisition system that needs to do the following:

- save high rate data (5Ms/s) to a file when an event occurs
- save low rate data to a file
- display the low rate data to the user interface

I was thinking about using a continuous acquisition architecture with a circular buffer but I'm not sure if this is the best approach for handling the data.

Also, I'm not sure of the impact on PC performance?

Any insight would be apprciated.

[RIO-Todd]

A circular buffer would definitely work for the high-speed, continuous measurements you will be performing. The biggest issue will be whether the PC will be able to keep up and write 5 MS/sec. to file. I would recommend a fast processor with a good amount of RAM so the computer will be able write the data to file at a fast rate.

The optimal way to write to file when acquiring data at high speeds will be to stream to disk. When streaming to disk you take the steps of
1. Opening File
2. Write to file continuously in loop
3. Close file

By performing the opening and closing of the file outside of the loop, you will be able to optimize the speed of writing to file. I hope this helps.

Todd D.
Applications Engineer
National Instruments