SAMPLE: SmartApp.exe Accesses SMART Stats in IDE Drives

ID: Q208048

The information in this article applies to:

Microsoft Win32 Device Driver Kit (DDK), on platform(s):
- Microsoft Windows 98
- Microsoft Windows 95

SUMMARY

SmartApp.exe is a sample Win32 application that demonstrates how to access the SMART (Self Monitoring, Analysis and Reporting Technology) capabilities built into IDE disk drives.

SMART technology is used to monitor disk drive degradation, in an effort to predict future catastrophic disk failure. For more information about SMART technology, see the REFERENCES section at the end of this article.

While this article primarily centers on using SMART technology with Windows 95 and Windows 98, it also includes information about how to modify SmartApp.exe to work with Windows NT and Windows 2000.

MORE INFORMATION

The following file is available for download from the Microsoft Software Library:

SmartApp.exe

Release Date: Feb-04-1999

For more information about downloading files from the Microsoft Software Library, please see the following article in the Microsoft Knowledge Base:

Q119591 How to Obtain Microsoft Support Files from Online Services


   FileName                Size
   -----------------------------

   SMARTAPP.C              17776
   SMARTAPP.H               1613
   SMART.H                  9857
   SMARTAPP.DOC            74240

Using the SMARTAPP sample code

SmartApp.exe is a console application that you run from a DOS command prompt. You should set up your command prompt window for 43 or 50 lines or direct the program's output report to a file (for example, type SmartApp.exe >c:\print.txt) because SmartApp.exe can report over 25 lines of text data. Following is a sample report produced by SmartApp.exe:


SMARTVSD opened successfully
DFP_GET_VERSION returned:
   bVersion        = 1
   bRevision       = 2
   fCapabilities   = 0x7
   bReserved       = 0x0
   bIDEDeviceMap   = 0x1
   cbBytesReturned = 24
SMART Enabled on Drive: 0
   cbBytesReturned: 12
Drive 0 is an IDE Hard drive that supports SMART
   #Cylinders: 4960, #Heads: 16, #Sectors per Track: 63
   IDE TASK FILE REGISTERS:
      bFeaturesReg     = 0x0
      bSectorCountReg  = 0x1
      bSectorNumberReg = 0x1
      bCylLowReg       = 0x0
      bCylHighReg      = 0x0
      bDriveHeadReg    = 0xA0
      Status           = 0x50
   Model number: WDC AC22500L
   Firmware rev: 40.44T40
   Serial number: WD-WM3493798728
   cbBytesReturned: 512
Data for Drive Number 0
Attribute Structure Revision          Threshold Structure Revision
             5                                      5
       -Attribute Name-      -Attribute Value-     -Threshold Value-
 1 Raw Read Error Rate              200                   51
 4 Start/Stop Count                 100                   40
 5 Reallocated Sector Count         200                   0
 A Spin Retry Count                 100                   51
 B Calibration Retry Count          100                   51
C7 (Unknown attribute)              200                   0
C8 (Unknown attribute)              100                   51

The Attribute fields are defined (and refined) solely by the disk drive OEM manufacturers.
The source code (that is, Smart.h, SmartApp.h, and SmartApp.c) was compiled and tested using Visual Studio with Microsoft VC++ 5.0 as a console application.

Common Windows 95 Problems

SMARTVSD packs the structures for the DeviceIoControl in and out buffers differently from the default packing used by MSVC. The application needs to specify #pragma pack(1) to get the structure packing to match SMARTVSD.

SMARTVSD subtracts 1 from the size of the SENDCMDOUTPARAMS when it validates the size of the SENDCMDOUTPARAMS passed to it by the application. Using the above packing, the size of the structure in the SMART VSD doc would be 17 bytes long. SMARTVSD apparently compares the buffer size passed in DeviceIoControl to 16. This is presumably to discount the variable size buffer array at the end of the structure, which is defined as 1 byte long in the docs. The sizes of the SENDCMDINPARAMS and SENDCMDOUTPARAMS structures specified in the DeviceIoControl call should not include the variable size buffers located at the end of each structure.

Compiling and Using SmartApp.exe with Windows NT or Windows 2000

To compile SmartApp.exe for Windows NT or Windows 2000, comment out or delete the following line located at the beginning of SmartApp.c:


#define WINDOWS9X   // Define this to compile for Windows 9x

For Windows NT and Windows 2000, the IOCTL call for SMART_GET_VERSION always returns a bIDEDeviceMap value of 1. You must select the target physical drive using the CreateFile() function. Note that for Windows 95 and Windows 98, the target physical drive is selected after inspecting bIDEDeviceMap. When the symbol WINDOWS9X is not defined (for example, when you are compiling SMARTAPP for the Windows NT or Windows 2000 environment), SMARTAPP currently only opens and reports the first physical drive, using the following:


CreateFile("\\\\.\\PhysicalDrive0",GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL)

To view other drives, change the PhysicalDrive parameter to a value other than 0. Note that you can also open a drive by specifying the drive letter. For example:


CreateFile("\\\\.\\c:",GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL)

SMARTVSD Troubleshooting Checklist

If opening SMARTVSD fails in Window 95 or Windows 98, one of the following might be the cause:

You are using the original version of Windows 95, which does not support SMART (the SDI_506.PDR port driver does not contain IDE PASSTHROUGH functionality).

SMARTVSD.VXD is not installed in the \windows\system\iosubsys directory.

You did not restart after installing SMARTVSD.VXD.

Your filesystem is running in Compatibility Mode (see the System Properties dialog box, click the Performance tab). This means that the protected mode IOS subsystem, containing SMARTVSD, is being bypassed.

Your system does not have any IDE drives. ESDI_506.PDR does not remain resident if there are no IDE drives.

Your IDE drives are using a third-party SCSI miniport driver instead of Microsoft's ESDI_506 driver.

Windows 98 inadvertently omitted SMARTVSD.

If SMARTVSD opens, but you fail to get meaningful data, the IDE drive might not support SMART (especially older drives).

Common Questions

How does IDE hardware report that it supports SMART functionality?

This information is described in detail in the ATA3 or ATA4 specifications (see References at the end of this article). Specifically, Word 82 Bit 0 in the Identify Device structure indicates the drive supports SMART.

How does SMARTVSD communicate with the hard drive(s)?

SMARTVSD is an IOS layered-hierarchy VSD (Vendor Supplied Driver). At the "top" side, SMARTVSD provides the DeviceIoControl functionality to communicate with WIN32 applications. At the "bottom" side, SMARTVSD communicates with the IDE device driver (ESDI_506.PDR) using an API called IDE Passthrough.

IDE Passthrough was added to the OPK1 version (and later) of Windows 95. For additional information about this mechanism, please see the following article(s) in the Microsoft Knowledge Base:

Q196550 HOWTO: Access IDE Controller Registers Using IDE Passthrough
You can use IDE Passthrough to read or write the IDE controller's registers, from your own IOS layer VSD (Vendor Supplied Driver).

Additional Considerations

Microsoft does not recommend replacing SMARTVSD with your own implementation. For example, if you want to make your own SCSI miniport respond to the SMART API (SMARTVSD works only with devices on the IDE bus, ignoring devices on the SCSI bus). If you do this, you will disable SMART functionality for other third-party IDE devices that use ESDI_506.

REFERENCES

Small Form Factor Committee (SFF) specifications:

ftp://fission.dt.wdc.com/pub/standards/SFF/specs/

SFF-8035i (Self-Monitoring, Analysis and Reporting Technology, Version 1.0 May 3, 1995)

INF-8055i (S.M.A.R.T. Applications Guide for the ATA and SCSI interfaces)

ATA Specifications:

ftp://fission.dt.wdc.com/pub/standards/ata/

ftp://fission.dt.wdc.com/pub/standards/ata/ata-3/ata3-r6.doc

Microsoft Smart IOCTL API Specifications:

http://premium.microsoft.com/msdn/library/specs/d4/iocltapi.htm

http://www.microsoft.com/hwdev/download/respec/iocltapi.rtf

Miscellaneous Resources:

Check out the web sites of companies that manufacture IDE drives, such as Western Digital, IBM, and Seagate to obtain additional manufacturer-specific information about SMART technology.

Additional query words:


Keywords          : kbtool kbStorageDev kbWinOS95 kbWinOS98 
Version           : WINDOWS:95
Platform          : WINDOWS 
Issue type        : kbhowto

Last Reviewed: March 6, 1999