http://tict.ticalc.org/docs/J89hw.txt contains all the 89 HW info you want. I do ASM, no C so I just use move,and,or commands to set the ports. BTW, you can always read old mailing-list-posts on www.ticalc.org . Good luck Cheiz > > Does anyone know how I can change how often interrupt 5 fires (in TIGCC)? > I'm sorry if this has already been answered, but I'm new to this list. > > Thanks, > Brett > > >