george.kontogiorgos Posted January 17, 2022 Share Posted January 17, 2022 Hello, I'm doing some experiments with data gather system and I relized that the gather program missed some samples. The pointer Sys.PhaseSamples presented a more samples number than line numbers on the gather text file. The difference is about 20 samples but it is not repetitive for every gather. The gather setup was did on IDE Terminal as follows: Gather.PhaseEnable=0 Gather.PhaseAddr=Sys.PhaseCount.a Gather.PhaseItems=1 Gather.PhasePeriod=1 Gather.PhaseEnable=1 Gather.PhaseEnable=0 Gather.PhaseMaxSamples=500000 After I issued the gather program with wait option on Linux: ./gather_csv -p -w > /var/ftp/gather/test1.txt Triggered the rotative gather on IDE Terminal: Gather.PhaseEnable=3 After some time, usually when Gather.PhaseSamples > Gather.PhaseMaxSamples (To check the rotative buffer), I stopped the data acquisition: Gather.PhaseEnable=0 Gather.PhaseEnable=1 Gather.PhaseEnable=0 The last gather gave me Gather.PhaseSamples=32818200. The first line of data acquisition file test1.txt (After Waiting to phase gather) is 71693224 phase counts and the last line of the same file is 104511413 phase counts. The difference is 32818189, so threre are 32818190 samples because we have to take the first line in account. So this data acquisition lost 10 samples this time. I don`t know if there is any delay on the gather system at the begining or at the end of the acquisition due to initialization or finalization of the program respectively and this lead to missing some samples. The difference between one sample and another is 1 in every line (I tested it with a Python script), according to Gather.PhasePeriod=1. This led me the conclusion that these lost samples are not at the middle of the gather. I would like to know why I`m losing samples and understand it to set up things correctly for future applications. Thanks in advance. Quote Link to comment Share on other sites More sharing options...
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