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<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial">Dear Fieldtrip users and developers,<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial">Using Fieldtrip buffer for a BCI loop (in realtime), I want to measure the delay introduced by the use of the buffer.<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial">I use two simple programs to measure it : the first one sends data to a buffer and writes CPU time in a file when a rising edge was detected in
the signal sent ; the other program requests the data and also writes CPU time in a file when the same rising edge is detected in the signal received.
<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial">I checked that the delay introduced by the detection and file writing is insignificant (0.5 to 5 µs). On my computer, with 32 channels signal and
chunks of 8 to 32 points, I measured very variables delays, also after deactivating the anti-virus : 1ms to more than 45ms.
<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial">Do you know what it is due to, if I can reduce it or if I can make it less variable ?<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial">Thank you in advance.<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Arial"><span lang="EN-GB" style="font-size:
10.0pt;font-family:Arial">Amélie<o:p></o:p></span></font></p>
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