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We appreciate your patience as we improve our online experience.
03-13-2008 03:24 PM
03-13-2008 03:37 PM
Thanks John for your advice.
The reason I don't use event counting is it doesn't provide a way to hardware reset its value. Because the vi is going to run over a long period time and the electrical noise may be high so I need to periodically correct the time with a known absolute time source which is GPS 1 PPS signal. If the timebase is not refreshed regularly, an accumulated timestamp error may become larger and larger.
The GPS unit will fire a 1 PPS signal on each even GPS second and also output a string message containing the time the current 1PPS signal represents via serial port.
So my vi will read this serial port and refresh the timebase variable in my vi which is shown in the vi I posted as i try to keep problem focused.
Feilong
07-13-2012 03:25 PM
Hello Mr. Bongaarts
This does help to some extents. Would you do me an favor to find me some literatures/articles concerning the operation of "Arm Start Trigger", also its relationship/differences with "Start Trigger"?
I was also told previously that the differences between "Arm Start Trigger" and "Start Trigger" is about synchronization, once multiple tasks are going to be synchronized, then it is where "Arm Start Trigger" comes in, would you clarify this a bit please?
I really appreciate your help and look forward your response.