It had to be something stupid. The graphs were plotted OK but then erased and I always missed it. I think what happened was that, in order to be certain the array was kosher, I serial printed the whole thing for the first time and that gave me a chance to see the graph. The commands were kosher but the order was wrong and an extra flag was required. I believe I originally had the order right but changed it to simplify the change in the text along the x-axis.
