I have written a LabVIEW device driver for a piece of non-NI hardware. I am mimicking the DAQmx drivers as closely as possible. My Read VI outputs an array of waveform data for the 8 channels on the device. Since I get an array of doubles from the low level device driver, I build the waveform as follows:
1.) Get the current time, the # of samples acquired, and the data acquisition rate
2.) Divide the # of samples by the acquisition rate, which gives me the acquisition duration
3.) Subtract the acquisition duration from the current time to get t0
4.) Take the inverse of the acquisition rate to get dt
The problem I'm having with this approach is that there seems to be some overlapping between samples with regard to the timestamps. If I wire these values in to a chart, the chart is continuously refreshed and all previous data is no longer displayed. I really would like it if each new iteration of waveforms was a perfect continuation of the previous iteration.
Does anyone have some experience with this kind of problem and could give me feedback?
