Pavel Roskin wrote: > AWARD BIOS on my machine returns: > ax bx cx dx > dl=0 0000 0000 0000 0001 > dl=7 0000 0004 4F12 0101 I suppose the first line is for dl=7? Otherwise I'm puzzled. > I suppose that if sectors=0, the disk doesn't exist. Yes, that seems ok. > I'm hesitating whether the check for ah should be kept. > Is it possible that other BIOS'es return (cl != 0) for non-existing drives > along with an error code in ah ? > > If yes, then a more complicated check should be done. I'm not sure, but I think it's better to check AH too. That won't hurt. /Peter