I assume that what you mean is that if you run the aquisition more than once you want to keep the samples from the previous runs on the graph...right? Like a chart but with XY functionality.
In that case you will need to make a buffer, e.g. a functional global style rotating buffer (If you can decide on the maximum number of samples to hold in the buffer you can work on a preallocated array and save lots of memory and get much better speed so that would be preferable).
