I am kinda new to asm so be gentle if the answer to this question is simple. I am thinking of adding API to my Os, so I could make programs that run only on my Os...can I, in the programs for my Os, say something like "HEIGHT=58" and have my Os see it and put it to use? Also I wondered if is possible to put any file format on a ti-86 (my Os will be for 86), and if so, can I put a DLL on the calc and use it in my Os? Thanks