Multiple Display Outputs

Is it possible to direct screen output to a second monitor via a comm port? Seems to me that I saw someone do a powerpoint demo where the presentation was directed to an alternate video display.  The audience didn't see the behind-the-scenes loading and unloading of presentations, just the output.

Can I do the same thing in VB5?  Any tips or hints in coding?

Thanks,
VBert
LVL 1
VBertAsked:
Who is Participating?
 
seliousCommented:
Ouch, that's difficult. Indeed, WIndows 98 seems to support multiple videocards (like multiple SCSI cards, it's possible).

But you'll need some assembly or C (assistance)...

If you put two video-cards (sVGA with 1 MB) in your PC, your BIOS searches one, untill he finds one. Than, that one is used (hopefully, but don't be scared when both monitors give an image) by all programs. The other one is somewhere else in your system and can be reached dirrectly from your hardware through I/O ports and that sort of stuff.

From here you must find the VGA specifications (search at assembly sites) and use some PC tool to check out all used IRQ's and that sort of stuff. Now use your manuals to program the card apperently not used.

You need some ActiveX-dll to do the I/O, but they may be availlable.

Very nice idea, cause you'll control the image on the other screen. It would be nice not to use W98 for this, cause than you'll be dealing with windows and stuff (unless you would like so).
0
 
DalinCommented:
Vbert
I believe the demo you see is from a computer that support an extra monitor. (most notebooks do). I don't think you can do it with a comm port to a monitor.
Regards
Dalin
0
 
LlandrCommented:
Windows 98 supports this (someway).
0
Ultimate Tool Kit for Technology Solution Provider

Broken down into practical pointers and step-by-step instructions, the IT Service Excellence Tool Kit delivers expert advice for technology solution providers. Get your free copy now.

 
ESICommented:
Llandr : Any Window98 API calls welcome !!!
0
 
DalinCommented:
Llandr,
Do you mean win98 support an extra monitor by using a comm port?  Then you need a hardware to adapt a comm port ( 9 -pin) to a monitor connect...
It can't be a simpling call APIs...Can it?

 
0
 
michelvCommented:
Windows '98 supports multiple monitors: You need two have two VGA-cards installed, and then Win98 can use the two vga-cards to display the presentation on one screen, and the loading and stuff you want to do on the other monitor. Driving a monitor from a COM port just can't be done, because:

1. COM-output is very different from VGA-input
2. COM-port speed is too slow (I guess...otherwise all monitors would be driven from cheap COM-ports instead of expensive (talking 'bout the ol' days...:) VGA-cards...)

Greetz, Michel
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.