>>I was looking at usgard.h, and I noticed the OP registers. I heard >>that >>on the TI-86 they are used for math operations. Can they be used on >>the >>TI-85 in the same manner? In all of the tutorials and source that I >>have >>read, I have never seen them mentioned before. Thank you. Normaly Ya can do this ! but t'care of strange reactions (there's something that I doon't understand...) Good luck!