Int 13H [PC] [AT] [PS/2] Function 09H Initialize fixed disk characteristics

Initializes the fixed disk controller for subsequent I/O operations, using the values found in the ROM BIOS disk parameter block(s).

Call with:

AH = 09H

DL = drive

80H—FFH fixed disk

and, on the PC/XT Vector for Int 41H must point to disk parameter block

or, on the PC/AT and PS/2 Vector for Int 41H must point to disk parameter block for drive 0 Vector for Int 46H must point to disk parameter block for drive 1

Returns:

If function successful

Carry flag = clear

AH = 00H

If function unsuccessful

Carry flag = set

AH = status (see Int 13H Function 01H)

Notes:

This function is supported on fixed disks only.

For PC and PC/XT fixed disks, the parameter block format is as follows:

Byte(s) Contents 00H—01H maximum number of cylinders 02H maximum number of heads 03H—04H starting reduced write current cylinder 05H—06H starting write precompensation cylinder 07H maximum ECC burst length 08H drive options

Bit(s) Significance (if set) 0—2 drive option 3—5 reserved (0) 6 disable ECC retries 7 disable disk-access retries

09H standard time-out value 0AH time-out value for format drive 0BH time-out value for check drive 0CH—0FH reserved

For PC/AT and PS/2 fixed disks, the parameter block format is as follows:

Byte(s) Contents 00H—01H maximum number of cylinders 02H maximum number of heads 03H—04H reserved 05H—06H starting write precompensation cylinder 07H maximum ECC burst length 08H drive options

Bit(s) Significance (if set) 0—2 not used 3 more than 8 heads 4 not used 5 manufacturer's defect map present at maximum cylinder + 1 6—7 nonzero (10, 01, or 11) if retries disabled

09H—0BH reserved 0CH—0DH landing zone cylinder 0EH sectors per track 0FH reserved