Read and write a digital Signal of 50ns

[Patrick-Did]

Dear Lab-View -Users,

I want to achieve with my NI 6602-Board the following application.

I have two photon detectors after a beamsplitter. Each of them clicks when a photon arrives: They never click on the same time together. The Signal of the detector is a TTL Signal of 100ns width. The signal of each detector has a (random) frequency of 6 kHz.
Now I want to save in a .txt file the correct order of the clicks of the detectors: A,B,B,B,A,B......

I have realized this in LabView with two digital inputs. When the state of the digital signal is changed to "1", then the letter A is saved in a file (see attachment).
Now the problem is, that the vi works, but it works to slow. It register only 800 signals in one second.

When I displace the detector Signals with a TTL function generator of 100 kHz the vi works well!

Has anyone an idea how I can make the vi faster? Or is my application for the 6602 board not convenient.

Thank you for your answers.
Regards,
Patrick

[Jan_Kniewasser]

Hy Patrick,

first of all I would recommend, that you include in your while loop a timing function such as the "Wait (ms)"- or "Wait Until Next (ms) Multiple"(recommended)- function out of the timing pallete with just a smal time constant. By the way you can find a lot of information to "loop timing" in the discussion forum.

The best way to find out if LV is fast enough(I think so), is to use the given examples for digital measurement. (See attached .jpg)

Hope I could help you with this.

Best wishes,

Jan Kniewasser

National Instruments