Article ID: 62571 - View products that this article applies to.
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The BIOS Interrupt 13H uses a zero-based number for floppy disk drives ("A"= 0, "B"= 1, and so on), and a zero-based number with the high bit (bit 7) set for hard disks ("C"= 80H, "D"= 81H, and so on).
You can use the following algorithm to convert any logical drive letter (ASCII) to the drive numbers that Interrupt 13H uses:
Article ID: 62571 - Last Review: November 16, 2006 - Revision: 2.1