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I want to boot a CD-ROM image at Bochs, but I need it's cylinders, heads and the Sectors per track. But how I can get this values from the disk image(*.ISO)?

I'm on Windows, but I have Cygwin installed

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Since it's a CD the number of physical heads is 1 (one), cylinders is 1 (one) and tracks is 1 (one). I'm assuming you need to lie to some software god to make something work. Since a sector has 256 bytes, just get the number of sectors by dividing the size of the CD.iso by 256 and make up values for cylinders * heads * spt that equal that number. It won't matter what you pick as long as the final value of the multiplication is equal to iso_size_in_bytes/256.

Caveat: I'm not a Bochs user (yet) but I'm assuming you want to create a virtual HD to load this iso onto and the Cyl/trk/spt info is going to be used to specify the virtual HD size.

Added: From your data I calculate 583440 sectors, which would give as one possible organization : 2431 cyl, 15 hds, 16 spt. 2431 * 15 * 16 * 256 is 149360640 which equals your iso size.

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No, what I'm trying is a TinyXP disk image. But English isn't my mother language, then it's very difficult to understand you. Could you be more specific? The size of the image is 149.360.640 bytes. – Nathan Campos Sep 8 '10 at 15:26

As far as I know, you only need the CHS (cylinders/heads/sectors) counts for disk images. Just be sure to change Type of ATA device from disk to cdrom.

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