Here's a possibly stupid question... I may have mentioned it earlier, but I got a copy of PDPXASM and I'm playing with it. Just pitching code at the 11/83 to see what I can make it do... Anyway, I'm playing with telling the RL02 what to do. Push the head around, write things, etc... Anyway, Is there a way to, given the the sector number, figure the head/cylinder/sector? Also, is there some mechanism to keep me from screwing up and sending the heads below track 0 or past 512? By the figuring CHS question, I mean this: I want to make a single routine I can call to position the head whereever and dump a sector to disk, but I don't want to have to know the disk geometry to do it. I pass to it a unit number, RAM start address, and a sector number. Now how do I divide the sector number to get the C/H/S? And I don't want to have to use floating-point to do it... -------