typedef struct _CM_INT13_DRIVE_PARAMETER {
USHORT DriveSelect;
ULONG MaxCylinders;
USHORT SectorsPerTrack;
USHORT MaxHeads;
USHORT NumberDrives;
} CM_INT13_DRIVE_PARAMETER, *PCM_INT13_DRIVE_PARAMETER;
CM_INT13_DRIVE_PARAMETER defines a device-type-specific data record that is stored in the \\Registry\Machine\Hardware\Description tree for a disk controller if the system can collect this information during the boot process.