Fetching in Chunks With ni5660 VIs Results in Same Data Being Fetched RepeatedlyHardware: Modular Instruments>>RF Measurement Devices>>PXI-5660
Problem: When fetching in chunks using the ni5660 VIs, the same data keeps getting fetched on each loop iteration. Solution: When acquiring large amounts of data with the NI 5660 you may want to fetch the data in chunks from the digitizer and process each chunk individually. This is still a single, finite acquisition, but the fetching is broken up into smaller pieces to better accommodate computer memory. When ni5660 Configure for IQ is configured for a FINITE acquisition, the 'Fetch Relative To' property in NI-Scope is set to 'Pretrigger'. If multiple fetches are called then the fetch starting point is always at the beginning of the data set. This results in the same data being fetched on each iteration. There are several ways to correct this problem: 1) Add a NI-Scope Property Node somewhere after ni5660 Configure for IQ. Set the 'Fetch Relative To' attribute to 'Read Pointer' so that each fetch grabs data starting at the end of where the last fetch finished. OR 2) Set Acquisition Type to Continuous in ni5660 Configure for IQ. Related Links: Attachments:
Report Date: 05/24/2006 Last Updated: 05/24/2006 Document ID: 3XNF850M |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
