Program Delay but miss the trigger in the 6602

[GraceSun]

I want to make a trigger (10 Hz, 100 ms separation) delay as long as slightly less than 100 ms. For that, I set the source (20 MHz internal) and gate (10 Hz external). But the problem is that I missed a trigger whenever I changed the value n (n=1 means 50 ns). It gets worse as the delay is longer and closer to the next trigger. Practically, I used "Counter Set Attribute.vi" to change n and "Counter Control" to "program". I think it seems to do stop (or reset) and reprogram or something like that. My understanding is that the counter can delay up to less than 100 ms (in our case) without missing the pulse in the hardware level. In the hardware level, can I re-register only the number "n"? Your manual does not give any clue
about my question.
Finally, I wonder what is "program", "prepare" and "arm". Do I have to do "program" whenever I change the delay time?
Thank you for your kind reply in advance.

[chericks1]

Dear GraceSun,

To address your question, whenever you switch counters (which is what I think you mean by switching "n"), you have to reconfigure and start the counting acquisition. This is done using Program, which prepares and arms the counter, or Prepare and then Arm separately. Prepare sets up the counter completely except for the arming and Arm starts the acquisition.

I'm assuming this configuration time is what is causing the hardware to miss the trigger.

Let me know if you have any further questions or if this does not resolve your issue.

Thanks again and have a great day!

Chad AE
Applications Engineer - National Instruments