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    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 7=1 if disable disk-access retries
                 bit 6=1 if disable ECC retries
                 bits 3-5=0
                 bits 0-2=drive option
    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
                 bits 6-7=nonzero (10, 01, or 11) if retries disabled
                 bit 5=1 if manufacturer's defect map present
                         at maximum cylinder + 1
                 bit 4=not used
                 bit 3=1 if more than 8 heads
                 bits 0-2=not used
    09H-0BH      reserved
    0CH-0DH      landing zone cylinder
    0EH          sectors per track
    0FH          reserved
                                    -♦-