[Dsg-hallb_magnets] Results of Fast-DAQ time gap investigation

[Tyler Lemon]

Hello, 

The results of my investigation of the time gaps are as follows: 


    1. Fast-DAQ data is sent at 10kHz to EPICS (2000 samples every 5Hz). 
    2. There are no time gaps in data from FPGA seen in LabVIEW. 
    3. There are no time gaps in LabVIEW before data is sent to EPICS. 
    4. There are no time gaps in data when viewing shared variables used to send data to EPICS. 
    5. There are no time gaps in data on EPICS Live Fast-DAQ screen. 
    6. There are time gaps in data recorded by EPICS. 
    7. There were no time gaps in recorded data when data was sent to EPICS at rate of 1Hz. 
    8. Time gaps first appeared after upping data rate to EPICS to 5Hz. 
    9. There have been no changes to how LabVIEW processes Fast-DAQ data besides increasing the EPICS data rate to 1Hz to 5Hz. 

Because of these findings, the time gaps are most likely caused by the write speed to disk for the EPICS data logging. The cRIO and LabVIEW would not have any affect on the time gaps seen. 

Best regards, 
Tyler 
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