function GetHDSerialNo: string;
begin
Result := GetIdeHDSerialNo;
if Length(Result) = 0 then
 Result := GetScsiHDSerialNo;
end;

function GetIdeHDSerialNo: string;
const
IDENTIFY_BUFFER_SIZE = 512;
type
TIDERegs = packed record
 bFeaturesReg: BYTE; //Used for specifying SMART "commands".
 bSectorCountReg: BYTE; //IDE sector count register
 bSectorNumberReg: BYTE; //IDE sector number register
 bCylLowReg: BYTE; //IDE low order cylinder value
 bCylHighReg: BYTE; //IDE high order cylinder value
 bDriveHeadReg: BYTE; //IDE drive/head register
 bCommandReg: BYTE; //Actual IDE command.
 bReserved: BYTE; //reserved for future use. Must be zero.
end;
TSendCmdInParams = packed record
 //Buffer size in bytes
 cBufferSize: DWORD;
 //Structure with drive register values.
 irDriveRegs: TIDERegs;
 //Physical drive number to send command to (0,1,2,3).
 bDriveNumber: BYTE;
 bReserved: array[0..2] of Byte;
 dwReserved: array[0..3] of DWORD;
 bBuffer: array[0..0] of Byte; //Input buffer.
end;
TIdSector = packed record
 wGenConfig: Word;
 wNumCyls: Word;
 wReserved: Word;
 wNumHeads: Word;
 wBytesPerTrack: Word;
 wBytesPerSector: Word;
 wSectorsPerTrack: Word;
 wVendorUnique: array[0..2] of Word;
 sSerialNumber: array[0..19] of CHAR;
 wBufferType: Word;
 wBufferSize: Word;
 wECCSize: Word;
 sFirmwareRev: array[0..7] of Char;
 sModelNumber: array[0..39] of Char;
 wMoreVendorUnique: Word;
 wDoubleWordIO: Word;
 wCapabilities: Word;
 wReserved1: Word;
 wPIOTiming: Word;
 wDMATiming: Word;
 wBS: Word;
 wNumCurrentCyls: Word;
 wNumCurrentHeads: Word;
 wNumCurrentSectorsPerTrack: Word;
 ulCurrentSectorCapacity: DWORD;
 wMultSectorStuff: Word;
 ulTotalAddressableSectors: DWORD;
 wSingleWordDMA: Word;
 wMultiWordDMA: Word;
 bReserved: array[0..127] of BYTE;
end;
PIdSector = ^TIdSector;
TDriverStatus = packed record
 //驱动器返回的错误代码，无错则返回0
 bDriverError: Byte;
 //IDE出错寄存器的内容，只有当bDriverError 为 SMART_IDE_ERROR 时有效
 bIDEStatus: Byte;
 bReserved: array[0..1] of Byte;
 dwReserved: array[0..1] of DWORD;
end;
TSendCmdOutParams = packed record
 //bBuffer的大小
 cBufferSize: DWORD;
 //驱动器状态
 DriverStatus: TDriverStatus;
 //用于保存从驱动器读出的数据的缓冲区，实际长度由cBufferSize决定
 bBuffer: array[0..0] of BYTE;
end;
var
hDevice: THandle;
cbBytesReturned: DWORD;
//ptr : PChar;
SCIP: TSendCmdInParams;
aIdOutCmd: array[0..(SizeOf(TSendCmdOutParams) + IDENTIFY_BUFFER_SIZE - 1) - 1] of Byte;
IdOutCmd: TSendCmdOutParams absolute aIdOutCmd;

procedure ChangeByteOrder(var Data; Size: Integer);
var
 ptr: PChar;
 i: Integer;
 c: Char;
begin
 ptr := @Data;
 for i := 0 to (Size shr 1) - 1 do
 begin
 c := ptr^;
 ptr^ := (ptr + 1)^;
 (ptr + 1)^ := c;
 Inc(ptr, 2);
 end;
end;
begin
Result := ''; //如果出错则返回空串
if SysUtils.Win32Platform = VER_PLATFORM_WIN32_NT then
begin //Windows NT, Windows 2000
 //提示：改变名称可适用于其它驱动器，如第二个驱动器： '\\.\PhysicalDrive1\'
 hDevice := CreateFile('\\.\PhysicalDrive0', GENERIC_READ or GENERIC_WRITE,
 FILE_SHARE_READ or FILE_SHARE_WRITE, nil, OPEN_EXISTING, 0, 0);
end
else //Version Windows 95 OSR2, Windows 98
 hDevice := CreateFile('\\.\SMARTVSD', 0, 0, nil, CREATE_NEW, 0, 0);
if hDevice = INVALID_HANDLE_VALUE then
 Exit;
try
 FillChar(SCIP, SizeOf(TSendCmdInParams) - 1, #0);
 FillChar(aIdOutCmd, SizeOf(aIdOutCmd), #0);
 cbBytesReturned := 0;
 //Set up data structures for IDENTIFY command.
 with SCIP do
 begin
 cBufferSize := IDENTIFY_BUFFER_SIZE;
 //bDriveNumber := 0;
 with irDriveRegs do
 begin
 bSectorCountReg := 1;
 bSectorNumberReg := 1;
 //if Win32Platform=VER_PLATFORM_WIN32_NT then bDriveHeadReg := $A0
 //else bDriveHeadReg := $A0 or ((bDriveNum and 1) shl 4);
 bDriveHeadReg := $A0;
 bCommandReg := $EC;
 end;
 end;
 if not DeviceIoControl(hDevice, $0007C088, @SCIP, SizeOf(TSendCmdInParams) - 1,
 @aIdOutCmd, SizeOf(aIdOutCmd), cbBytesReturned, nil) then
 Exit;
finally
 CloseHandle(hDevice);
end;
with PIdSector(@IdOutCmd.bBuffer)^ do
begin
 ChangeByteOrder(sSerialNumber, SizeOf(sSerialNumber));
 (PChar(@sSerialNumber) + SizeOf(sSerialNumber))^ := #0;
 Result := Trim(StrPas(@sSerialNumber));
end;
end;

function GetScsiHDSerialNo: string;
type
TScsiPassThrough = record
 Length: Word;
 ScsiStatus: Byte;
 PathId: Byte;
 TargetId: Byte;
 Lun: Byte;
 CdbLength: Byte;
 SenseInfoLength: Byte;
 DataIn: Byte;
 DataTransferLength: ULONG;
 TimeOutValue: ULONG;
 DataBufferOffset: DWORD;
 SenseInfoOffset: ULONG;
 Cdb: array[0..15] of Byte;
end;
TScsiPassThroughWithBuffers = record
 spt: TScsiPassThrough;
 bSenseBuf: array[0..31] of Byte;
 bDataBuf: array[0..191] of Byte;
end;
var
dwReturned: DWORD;
len: DWORD;
sDeviceName: string;
hDevice: THandle;
Buffer: array[0..SizeOf(TScsiPassThroughWithBuffers) + SizeOf(TScsiPassThrough) - 1] of Byte;
sptwb: TScsiPassThroughWithBuffers absolute Buffer;
begin
Result := '';
sDeviceName := 'C:';
hDevice := CreateFile(PChar('\\.\' + sDeviceName), GENERIC_READ or GENERIC_WRITE,
 FILE_SHARE_READ or FILE_SHARE_WRITE, nil, OPEN_EXISTING, 0, 0);
if hDevice = INVALID_HANDLE_VALUE then
 Exit;
try
 FillChar(Buffer, SizeOf(Buffer), #0);
 with sptwb.spt do
 begin
 Length := SizeOf(TScsiPassThrough);
 CdbLength := 6; // CDB6GENERIC_LENGTH
 SenseInfoLength := 24;
 DataIn := 1; // SCSI_IOCTL_DATA_IN
 DataTransferLength := 192;
 TimeOutValue := 2;
 DataBufferOffset := PChar(@sptwb.bDataBuf) - PChar(@sptwb);
 SenseInfoOffset := PChar(@sptwb.bSenseBuf) - PChar(@sptwb);
 Cdb[0] := $12; // OperationCode := SCSIOP_INQUIRY;
 Cdb[1] := $01; // Flags := CDB_INQUIRY_EVPD; Vital product data
 Cdb[2] := $80; // PageCode  Unit serial number
 Cdb[4] := 192; // AllocationLength
 end;
 len := sptwb.spt.DataBufferOffset + sptwb.spt.DataTransferLength;
 if DeviceIoControl(hDevice, $0004D004, @sptwb, SizeOf(TScsiPassThrough),
 @sptwb, len, dwReturned, nil) and ((PChar(@sptwb.bDataBuf) + 1)^ = #$80) then
 SetString(Result, PChar(@sptwb.bDataBuf) + 4, Ord((PChar(@sptwb.bDataBuf) + 3)^));
 Result := Trim(Result);
finally
 CloseHandle(hDevice);
end;
end;