Then I would recommend to run the loop at a constant slow rate that ensure that the instrument can respond. The loop timing should never depend in the instrument response. What is the typical jitter in the response timing? What is the max?
Alternatively you could use an xy graph and some backend code to simulate a chart behavior. How many points do you expect? Size known before the program runs? Do you need to keep a constant buffer and discard old entries like in a chart?