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I am in the process of re-writing my bootloader. For some reason nobody uses the the INT 13h AH=08h method for detecting the sectors per track value of a floppy or harddrive. I guess its not reliable enough.

I have written some code to do so, but Im not sure if it will work on other peoples computers. Since we have started a Test bed forum, it would be nice if people could test to see if this method will work on your computer and if the value detected is correct.

It detects 18 sectors per track for floppy on my computer.
For some reason it wont let me access my HD, I guess my computer doesnt like me doing that. If anybody knows how to using this method and assembly code, then let me know and I'll see if I canget it to work with my existing code.

Test machine: HP 8200 Pentium 133, 60 GB 7200 HD, 256 MB of ram, builtin sound and video card.

Because the forum doesnt let you upload .com files, I had to put it into a .zip file.

Thanks in advance.




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afaik, there are ony two possible values with 3.5" disks:
18 sectors per track (1.44MB) or 9 sectors / track (720KB)

i guess most of the bootloaders ignore that check because they know the disk is 1.44 ...
btw, i'm not sure the BIOS can actually *detect* if it's a 1.44 or a 720 floppy ... it just relies on the information stored in the BPB in the bootsector ... as few of the custom-made bootloader will providee that BPB, the BIOS would give you irrelevant information ...