Hi, > Ohhh. I didn't know this. I have only the i386 Programmer's Reference > Manual that does not contain this type of info. Do you know if there is > a site link with this info? I found the information by accident searching the web for 'diskette parameter table' and '78'. The site was about the Win95 boot sector. I don't know any useful documentation about this matter on the web. I usually use the Intel Architecture Manuals and the Phoenix Bios User's Manual as references (neither of these contains the above information). > I agree with you that %bx already contain 0 so I do not have the answer > that you are looking for. Probably a more expert guy on this mail list > can help us. Actually %bx is probably non-zero, it simply contains the offset into the next 64k segment. Therefore %bx should be left alone. Otherwise the sectors that didn't fit into the current sector will be overwritten by successive reads. Clemens Buchacher -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/