USB-6366 取込遅延時間について

[KevWhat]

 取込遅延時間について

 USB-6366 からアナログ信号の取得を考えています。

 トリガはNI 側の内部クロック(フリーラン)でトリガをかけます。(例: N Samples, 10k samples to read, Rate  1kHz)

 この場合、NIの内部クロックでトリガが掛かってから、実際信号を取り込むまでの遅延はどれくらいになるのでしょうか?

 「よーいドン」して、信号が取れるまでどのくらいの遅延があるのでしょうか?

[KevWhat · Accepted solution]

Let me post in English.

Actual capturing Duration Need to know Actual capturing time from Generate Trigger (start trigger on PC) signal to triggered on USB-6366(Analog port: N Samples, 10k samples to read, Rate 1kHz).

 I can imagine, actual trigger generate timing depends on Computer processor process. therefore it can not be measured seriously. But just I want to know rough number like msec, nsec, usec oder.

[Y.Ueno（退職）]

Hello KevWhat,

The latency time from the software trigger until the DAQ device starts acquiring depends on the trigger detection time by the application (program), OS resolution, and the bus latency time. Please check the following pages.

• Delay with Trigger and First Sample on M, X, and E Series MultifunctionDAQ
• Generate Software Timed Trigger with NI-DAQmx in LabVIEW
• Accuracy of Software-Timed Applications in LabVIEW

When you acquire the finite sampling (10k samples to read, Rate 1kHz), It takes 10 seconds to get all datas, then DAQ device will send from FIFO buffer to Application. The process also has latency time. For the details, please refer to the links below.

• DAQmx Timing and Sample Rates
• Make it Faster: More Throughput or Less Latency?
  

By the way, If you want to post by Japanese, you can post Regional Communities "ディスカッションフォーラム（日本語）".

[KevWhat]

These information that you gave me are enough for me. Looks like, let me study from these information.

Thanks,