Bitset v2.04


Page last changed: April 06, 2006

This is a completely rewritten version of the former bitset app, now using this library to access DVD drives. Also, it is easier to use now, a bit more foolproof, and, especially, should no longer simply crash with bad input.


Usually, the following actions should suffice to make this application work:
  1. Download the binaries and unzip the rar file to a folder of your choice (should only include characters of your local charset, i.e. for example don't use cyrillic letters in the folder name if you are using an english windows)
  2. download an ASPI layer, for example Frog ASPI or Nero ASPI, and save the file into the same folder
  3. run install.bat. This will install bitset into the autostart using the following setting: set all drives for all supported DVD+ disc types to DVD-ROM.


LG drives:
The drive will memorize this setting until you switch it off (e.g. by switching the PC or the power supply of the external enclosure off)
Plextor/BenQ drives:
The setting stays permanent until it is changed again and survives reboots
NEC drives:
NEC drives support both permanent as well as non-permanent book type setting. This application only changes the non-permanent setting. Use Nero CD-DVD Speed or DVD Decrypter to change the permanent setting.

If you want to change the install.bat file, you can proceed the following way:

How to call bitset

bitset -drive=n -set:<settings> [-autostart]

where <settings> is a list of disc type and book types.

bitset -drive=1 -set:dvd+r=dvd-rom,dvd+rw=dvd+rw,dvd+rdl=dvd-rom
bitset -drive=3 -set:dvd+rw=dvd-ram
(note: this would only work on NEC drives and is probably a bad idea, and some NEC drives accept the setting, but ignore it)

The -autostart parameter makes bitset put itself into the auto start. If you want to verify that it worked, check the following registry key: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

Latest changes:

Before asking useless questions:

Bitsetting can only be done to the extent it is supported in the firmware of a drive. Don't ask me "can you make bitsetting on +RW work for LG drives?". Ask the LG technical support!


This software can perform bitsetting on the following drives:

Bitsetting capabilities:

Booktypes possible forNote
LGDVD+R, DVD-ROM-DVD+R DL, DVD-ROMSuperMulti drives older than GSA 4120B do not support bitsetting
PlextorDVD+R, DVD-ROM-DVD+R DL, DVD-ROMPlextor PX-740A is a BenQ drive!
BenQDVD±R(W), DVD+R DL, DVD-ROMsetting DVD+ discs of whatever type to DVD-R/DVD-RW/DVD+R DL is idiotic
NECDVD±R(W), DVD+R DL, DVD-ROM/-RAMsetting DVD+ discs of whatever type to DVD-R/DVD-RW/DVD+R DL/DVD-RAM is idiotic


Executing this file will have 2 effects: It will set all your drives it supports to DVD-ROM booktype, and it will add this utility to the autostart, setting all supported drives to booktype DVD-ROM after each reboot
will open the command line interface. The first time you use this app, you should launch cmd.bat and type bitset there, to see if your drives are detected properly.

Problems / TroubleShooting

If you get an error message about wnaspi32.dll not being found, install an ASPI layer, for example ForceASPI 1.7, Nero ASPI or Frog ASPI. The last 2 just need to be copied into your windows\system32 folder, choose one of those.

If your drive is connected via USB2/Firewire or if it doesn't work for whatever reason, try both Nero ASPI and Frog ASPI, as those work more reliably with this software than Adaptec ASPI. If this application crashes with either Nero ASPI or Frog ASPI, just try the other one, and report me this crash: It is not supposed to crash with either of them, so if it does, there is a bug.

In extremely rare cases, initializing the system ASPI can lead to a BSOD. I myself have experiences this with a i845E chipset in combination with Adaptec ASPI and Intel Application Accelerator. bitset removes itself from the autostart before initializing ASPI and add itself after all settings have been made. That means, in the unlikely case that this problem occurs, bitset will have removed itself from the auto start before a BSOD can occur, but will not have added itself back to the autostart. Thus, if this utility causes a BSOD due to this problem, it will not be autostarted with the next reboot.

Other operating systems than Windows

I won't support other operating systems. However, the source code is available, so anyone who wants to implement bitsetting for those drives for other operating systems can easily extract the necessary commands from the source code. For NEC drives, you can use binflash.


Alexander Noé

You can contact me in english, german or french.