Int 21h Function 440Dh Minor Code 60h (FAT32)

Returns the device parameters for the specified block device.

mov  bx, Drive           ;See below
mov  ch, DeviceCat       ;See below
mov  cl, 60h             ;Get device parameters
mov  dx, seg DriveDP     ;See below
mov  ds, dx
mov  dx, offset DriveDP  ;ds:dx points to a device parameters structure
mov  ax, 440Dh           ;IOCTL for block device
int  21h

jc   error_handler       ;carry set means error

Parameters

Drive

Specifies the drive for which parameters are requested (0 = default drive, 1 = A, 2 = B, and so on).

DeviceCat

Specifies the expected format of device parameters information structure.

Value	Expected device parameters structure
08h	DEVICEPARAMS (FAT16 or FAT12 drive. This call will work on FAT32 drives, but results are not reliable. Use the 48h form for FAT32 media).
48h	EA_DEVICEPARAMETERS (FAT32, FAT16 or FAT12) This value is supported on Windows 95 OEM Service Release 2 and later.

Note: Because this call may be implemented in the device driver, the 48h form of this call may fail on FAT16 or FAT12 media. Therefore, applications making the 48h form of this call must fall back on the 08h form if the 48h call fails.

DriveDP

Points to the applicable device parameters structure containing the parameters for the specified block device. The format of the expected device parameters is indicated in the DeviceCat parameter.

The special functions member in the device parameters structure determines whether the function retrieves current or default information. If the member is set to 1, the function retrieves information about the current medium in the drive. If the member is set to 0, the function retrieves information about the default medium for the drive.

Return Values

If the function is successful, clears the carry flag. Otherwise, sets the carry flag and sets the AX register to one of the following error values.

Remarks

Get Device Parameters returns 0002h (ERROR_FILE_NOT_FOUND) if the specified drive number is invalid.