I am trying to trigger off or a zero crossing from (approximately) a sinusoid. The sinusoid is a bit noisy, so I am using a hysteresis level. The sinusoid is about 27kHz, and the PCI-6115 can sample at 10MS/s. When a trigger event occurs, I want to take 1 data point which needs to be stored in memory and later written to disk after the entire acquisition of many data points is over. The entire acquisition lasts approximately 10 seconds.
I've attached my vi showing how I am trying to do this. It seems like the triggering and single data acquisition can't keep up with the sinusoid. Any thoughts on what's going wrong?