Int 41  - System Data - Hard Disk 0 Parameter Table                        [B]


Note:  the default parameter table array is located at F000h:E401h in 100%
     compatible BIOSes; the pointer may be overridden by the hard disk
     controller's BIOS to support drive formats unknown to the ROM BIOS

See Also: INT 13/AH=09h,INT 1E,INT 46

Format of fixed disk parameters:
Offset Size    Description
 00h   WORD    number of cylinders
 02h   BYTE    number of heads
 03h   WORD    starting reduced write current cylinder (XT only, 0 for others)
 05h   WORD    starting write precompensation cylinder number
 07h   BYTE    maximum ECC burst length (XT only)
 08h   BYTE    control byte
          bits 0-2: drive option (XT only, 0 for others)
          bit 3:    set if more than 8 heads (AT and later only)
          bit 4:    always 0
          bit 5:    set if manufacturer's defect map on max cylinder+1
                (AT and later only)
          bit 6:    disable ECC retries
          bit 7:    disable access retries
 09h   BYTE    standard timeout (XT only, 0 for others)
 0Ah   BYTE    formatting timeout (XT and WD1002 only, 0 for others)
 0Bh   BYTE    timeout for checking drive (XT and WD1002 only, 0 for others)
 0Ch   WORD    cylinder number of landing zone (AT and later only)
 0Eh   BYTE    number of sectors per track (AT and later only)
 0Fh   BYTE    reserved