Thank you for your response.
I change to
>long Options = BACKGROUND + CONTINUOUS + RETRIGMODE + EXTTRIGGER + BURSTMODE;
>Sleep(100); //means you are looking for a trigger event 10 times per second, but you are expecting new data (retrigger) at 20 times per second, so this is too long a delay.
I used "Sleep(100)" to get started.
I used "Sleep(1)" in the loop.
I tried, but still no change.
But, when I tried changing the number of data from 1000 to 50, I was able to get it every 50mS.
Can I do what I want with a higher performance model? For example, a model with faster sampling rate...