How to realize 1ms timed loop in labview for arduino mega

[jinshanhai]

Hi

I am want to realize 1ms timer loop in arduino mega by using labview.

I have tried timed loop of labview with 1 khz clock and 1 ms period.But, I found in my physical oscilloscope that the actual loop time is 50 hz.

Could any one can help me to realize 1ms timed loop with labview?