Hi, I am a chemistry graduate student who is brand new to LabView. I am looking for some help with using the APD photodiode to count the number of photon. I want to gate the APD by applying on the APD input gate a TTL pulse (which will be generated by LabView 2014 via NI-USB-6251 BNC), I am trying to find a LabView program that can control USB-6251 to do photon counting, but I have no idea how to design a program. I was wondering is there any similar program that I can use? Any help would be greatly appreciated. Please let me know if you need any sort of additional information from me to understand what I am doing.