Description of program HDAT2

HDAT2 is program for test or diagnostics of ATA/ATAPI/SATA, NVMe, SSD and SCSI/USB devices.
This program cannot be run in DOS mode under Windows, only under real DOS system.
The exception is the demo version of the program.
You should make a DOS boot USB, floppy disk or CD/DVD and boot your system for it
and execute this program from that USB, floppy disk or CD-ROM.

HDAT2 program has 2 levels:

  • Device testing

    - main function is testing and repair (to regenerate) bad sectors for detected devices
    - you get much information about detected devices

  • File system testing

    - read/find/check items (MBR, boot, directories, etc.) of file system FAT12/16/32
    - check/remove (regenerates) bad sectors records, flags in FAT table


  • fully implemented commands: SET MAX, SET SECURITY, Device Configuration Overlay (DCO) and other
  • device access with interrupt 13h, direct via ATA/AHCI ports, with ASPI drivers
  • detects ATA/ATAPI/SATA/NVMe devices with on-board and add-on controllers
  • detects devices on AHCI and some RAID controllers
  • detects USB devices via USB ASPI driver or BIOS (if supported)
  • detects SCSI hard drives via BIOS interrupt 13h or ASPI drivers
  • other SCSI devices are detected via ASPI drivers only (must be loaded before);
    with ASPI drivers you will get more information about SCSI devices
  • test and repair device for bad sectors
  • many different test-functions for hard drives
  • resize ATA/SATA hard drives which supports SET MAX ADDRESS/EXT
    (supports 28/48-bits LBA addressing modes)
  • resize and change sector size of SCSI disks
  • drive lock detection via security feature (Security Menu)
  • S.M.A.R.T. functions for ATA/SATA,SCSI and NVMe drives only
  • information about devices (ATA/ATAPI, BIOS interrupt 13h, ASPI, EDD)
  • sector viewer for devices (also for USB, ZIP, CD-data discs)
  • to access ATA/SATA CD/DVD drive you don't need any driver or MSCDEX
  • enable/disable some features for direct-access devices
  • Device Configuration Overlay (DCO) feature set
    (you can restore a full capacity or allow/disallow some feature sets of hard drive)
  • SATA/NVMe: converts between 512e logical sector size and 4Kn, if supported
Known limitations for versions 5.x:

  • change SATA/RAID controller in BIOS from AHCI/RAID to IDE/ATA/legacy mode
  • the SATA/RAID devices will be detected only on ports 0-3
Known limitations for versions 6.x/7.x:

  • supports 32-bits AHCI only (this is not related to CPU type)
  • AHCI Port-Multiplier is not supported

Freeware License Agreement:

Program HDAT2 is freeware.

  • You are allowed to use this program on one or more machines at a time.
  • You are allowed to distribute this program as long as you do it without profit and without modifications to this license (you may not charge a licensing fee for the program).
  • You may redistribute this program included as a support tool for your programs, as long as you notify me by e-mail.
  • The software and related documentation are provided "as is", without warranty of any kind.

Minimal configuration:

  • CPU 386/486 with co-processor or higher
  • RAM 1 MB or more
  • DOS boot system

Program notice

HDAT2 is running in DOS protected mode and is compiled with a free 32-bits Free Pascal compiler v3.2.2.

Both program's level ('drive' and 'file') are integrated into one program.

DEMO Protected mode comments

File HDAT2DEM.BIX hold basic information for some devices (ATA, SATA, ATAPI, SCSI, NVMe and USB) and must be in the same directory with program HDAT2DEM.EXE.

Why demo? You can try this program in Windows without rebooting to pure DOS.
For example you can see:

- SMART information with some error logs
- Device Configuration Overlay data

This demo version is running only with 'Drive level' ('File level' is not available) and almost all commands will be aborted. All conflicts are simulated only: locked state, reduced size of hard drive, etc.

This demo version is running only under DOS or 32-bits Windows.