It looks like you're trying to do grayscale like this
), but usually we do grayscale like this
, which blends together much better. We can't reliably synchronize with the LCD on the TI-83+, plus we usually can't update the screen quickly enough to keep up anyway.
Actually the first one is how I drew grayscale. So you're saying that grayscale blends much better if I use a checkerboard pattern?