The complete cycle is time acquisition for software that had to set at function block “Wait 1 and Wait 2” which they are time loop of running cycle and also in separated loop. The program obtained input from channel “ai1” which is analog input and used acquisition mode: 1 sample (On demand). Then, we had a function generator to generate sine wave signal of 100 Hz. By testing the program, we vary running time of each loop and observed the behavior of the graph. We noticed that after we set running time of the second loop to 0 ms, the graph of data had been distorted because of second loop always running and faster than the first loop. Thus, the second loop interrupted the first loop which caused data distortion.