The VGA-dongle fits between VGA-card and monitor and just syncs to the vertical synchronization. That means the glasses are activated all the time, even in a standard screen mode.
There's a stereo reverse switch which has to be used very often (in 50 percent of the cases) since there is no way to tell the controller the stereo orientation. I like this switch more than the software solutions of many commercial shutterglasses controllers.

The only task of the user is to get an interlace or page-flipping stereo-3D image up there on the monitor-screen. The controller will just sync to it. No questions asked.

LCD-BIOS doesn't need any parameters anymore. Also functions like /lockflip which eats up valuable CPU-time isn't required. Please read the Drawback section for possible problems.

Always check the stereo orientation by using the reverse-switch at startup and from time to time during a stereo-session.
Beginners can easily miss the fact that the image is reversed, which results in eye&brain-strain and an unsatisfying 3D-experience.
 

To my knowledge the following commercial products might use controllers which are similar to the homebrew VGA-PT:

• i-Art Virtual Eyes (confirmed)
• APEC VR97 (confirmed)
• Cyberstuff Cyber3DVisor (?)

• One drawback of the homebrew VGA-PT (and similar products) is that it's working all the time. It has no auto-shut-off. (Is this really a drawback? Most manufacturers think so. - I don't think that's a problem.)
• Another drawback is the fact that you always have to set stereo orientation manually at startup and whenever the screenmode is changed. (Is this really a drawback? Most manufacturers think so. - I love this reverse switch.)
• There are no sync-doubler or line blanker capabilities yet.
• It's not compatible to Voodoo 1&2 add-on boards at the moment.
• In theory stereo is reversed each time the controller misses a sync. I don't know how often this happens. I have to investigate this further, but I think it's not loosing any syncs usually.

This happens with LCD-BIOS (and drivers based on it, like NuvFrag).
The problem seems to related to IRQ's and depends on the hardware configuration and the software used.
There are "jumps" or "jerks" in the page-flipping which are visible, even to the bare eye. In this case the stereo orientation flipps about every 1 to 5 seconds which renders the game/application useless.

Examples:
(from my system, must not apply to other configurations):

Nascar Racing: no problems
Whiplash: no problems as long as General Midi sound is deactivated
Magic Carpet: unplayable, no fix yet

This problem is one of the reasons why VRex is using interlace and tweaked page-flipping only and it's the reason why Stereographics uses white line code and it's the reason why H3D accepts properly done hardware page-flipping only (it switches to split-screen/sync-doubling when hardware p.-f. isn't available).
It also shows that there is at least one advantage of serial/parallal controllers. They don't loose the right stereo-orientation.
Commercial products which feature a controller similar to the homebrew VGA-PT (i-Art VirtualEyes, APEC VR97) are usually distributed with interlace drivers.

There seems to be no problem with interlace mode whatsoever. Interlace is a special case of hardware-page-flipping.

No matter how you put it, the VGA-PT controller is big fun anyway and worth a try!
 
 

• Read Donald "Mr. LCD-BIOS" Sawdai's comment on the problem.
• Use interlace instead of page-flipping whenever possible (i.e. use VR-BIOS instead of LCD-BIOS, use Windows instead of DOS, for example WinQuake instead of DOSQuake) .
• Use your old controller (parallel, serial or SimulEyes) on those page-flipping titles which don't behave well on the VGA-PT.
• Do NOT use DOS programs in the Windows DOS-box.
• Use LCD-BIOS instead of NuvFrag whenever possible (that's just a wild guess, but NuvFrag pings the parallel port which isn't needed for the VGA-PT)
• Start LCD-BIOS without parameters
• Start LCD-BIOS with different parameters ("Try with and without /LockFlip. Try /FastInt:-1 or /FastInt:-2.  Also try the /VBE2 switch.")
• Read the LCD-BIOS documentation for hints on IRQ/timing issues
• Try different system configurations.
• Turn off sound/midi/mouse
• Try different 3D- and VESA-drivers.
• Reboot your computer between experimental steps
• Look for TSR-programs which may cause trouble.
• Use hardware page-flipping instead of software page-flipping (more of a hint for the programmers, but they should know this already)

"To make the program run faster:
· Remove /LockFlip from the command line.
· Reduce x in /FastInt:x.  Negative values of x may be used and yield the fastest results.  For LCD glasses on the parallel or serial ports, negative x values will make the black band very large.  However, for LCD glasses directly attached to the video card, negative x values cause little change in image quality but a noticeable speed increase.

If the screen jumps around a lot while in 3D mode:
· Remove /LockFlip, /FastInt, /DelayFlip, and /HRefresh from the command line (be careful: these options may be buried in a batch file)."
 
 

How to make it

Hardware (VGA-card) Compatibility

You'll need a VGA-card which supports interlace and/or page-flipping. Many common chipsets support interlace. Almost all chipsets support hardware page-flipping. Only a few cards support neither of the two, such as the Voodoo 1&2 add-on boards. These boards might be able to perform software page-flipping, but I don't know of any current driver. They might be supported by SSDI in the future, but this is uncertain. Voodoo Rush boards do work with the VGA-PT since the signal is generated by an Alliance chipset, not by the Voodoo chips.

As far as I know the VGA-PT is 100% hardware compatible to the following commercial shutterglasses systems (appart from the TV/Video capabilities of some products and the known DRAWBACKS):
 

• 3DTV 3D Magic
• 3DTV 3D PCTV
• Nuvision 3D-SPEX
• Cyberstuff Cyber3DVisor
• Woobo Cyberboy
• Chinon Cybershades
• Stereographics SimulEyes
• VRex VRSurfer
• miro 3Dfanatix
• i-Art Virtual Eyes
• APEC Virtual Visor
• APEC VR97

• Kasan 3D-Max
• H3D Eyewear
• i-glasses
• VFX-1
• CyberMaxx

The VGA-PT controller should work with the following driver-software:

• LCD-BIOS
• Nuvision NuvFrag
• Nuvision WinSPEX
• APEC VR(97)-Viewer
• i-Art Win3D
• Stereographics SG-Toggle
• VRex VR-BIOS
• VRex SSDI
• VESA3
• The VGA-PT works also with programs which invoke interlace or page-flipping by themselves

• H3D-split-screen format and H3D-"synthetic interlace" isn't supported.
• Kasan 3D-BIOS isn't supported, because this driver looks for the 3D-Max ISA card.