IBM Personal Computer Technical Reference
  Software
    Operating Systems
      BIOSs
	Services
	  Disk Drive Controller
Int Function Description					   Version
-----==--==- ----------------------------------------------------- ----------
Int\21f\0D Buffer Flush
Int\21f\32 Drive Parameter Block Read (any drive)			 *
Int\21f\1F Drive Parameter Block Read (default drive) 		 *
Int\21f\19 Drive Return current
Int\21f\0E Drive Select
Int\21f\1C File Allocation Table Get	(any drive)
Int\21f\1B File Allocation Table Get	(default drive)
Int\21f\36 Free Space Get
Int\21f\69 Serial Number				      (DOS 4.0)
Int\21f\2F Transfer Address Get (DTA)
Int\21f\1A Transfer Address Set (DTA)
Int\21f\54 Verification Status Get (VERIFY)
Int\21f\2E Verification Status Set (VERIFY)
Int\13     BIOS Functions
Int\19     Bootstrap Loader
Int\1E     Drive Parameters (floppy drive)
Int\25     Absolute Sector Read
Int\26     Absolute Sector Write
Int\40     Hard Disk BIOS
Int\41     Drive Parameters (hard disk #1)		     (except PC1)
Int\46     Drive Parameters (hard disk #2)		     (AT, PS/2)
Int\76     Controller IRQ14 (AT, PS/2)
Int\0D     Hardware Interrupt Vector (hard disk)
Int\0E     Hardware Interrupt Vector (floppy disk)


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