Computer help forum: using one keyboard for two computers at the same time

This is sort of like what you are asking:
I want to control two cars running down different highways at the same time, can I use just one steering wheel?

Simple answer, no.
Think about what would happen if the computer-1 needed a press of a Return key to confirm the going to another site, and computer-2 needed a press of the Return key to confirm deleting all of your files. !!!! wait wait !!!

Using a KVM to switch between computer-1 and computer-2 is the solution you want. Else, just plug in 2 keyboards, one each into each computer.

yes U can!
see:
http://lifehacker.com/254648/hack-attack-control-multiple-computers-with-a-single-keyboard-and-mouse

You don't need a hardware switch to share one keyboard and mouse amongst several different computers. All you need is the free, cross-platform application, Synergy.

Synergy connects one keyboard and mouse to any computer on your network, making a dual- or triple-computer setup work more like a dual- or triple-monitor setup. Synergy even allows you to share clipboard data across your computers and operating systems.

It seems you could do 3 things:
1. Find your soldering iron and the right parts and make a prototype of a T-switch for a PS2-connector: 1 in, 2 out. Only 1 out should provide the power, the data should go from the 1 in to the 2 out.
2. Find or write software that emulates the keyboard or mouse on the second computer and gets it input data from the first computer (via any direct PC to PC connection). You might need to find or write software that provides the data also.
3. Find or write software on the first PC that emulates a mouse or keyboard for the second PC via some direct connection. A 9-ports serial connection seems the easiest to control, but not every PC nowadays comes with a good old serial port for a mouse or keyboard.

The problem that nobody, except you, wants it. So the market is very small. You'll have to make it yourself. If you find that difficult, you're the reason.

Personally, I think it's easier to use 2 fingers to press the enter key on 2 wireless keyboards located next to each other.

An alternative would be to have the presentations controlled by a program on a server that you instruct from your management console on some client. It might be easier to synchronize actions on 2 clients using some web-protocol (with flash or java on the client side) than by emulating hardware like a mouse or a keyboard. Consider a chess tournament that has a website that lets you have a live view at the games. The application in your browser (most often java) gets messages like "White played 17. Ra5" and shows it on the screen. Your application gets a message like "Switch to sheet 17" and does it. That's essentially the same.

It's a quite instructive assignment for an advanced (and rather specialized) class in web-development.


Kees

Would a USB hub work backwards?