Hello i was wondering something i have 3 computers with 3 lcds on my walls mounted problem is i have no room on my Desk for 3 keyboards and mouses. I was wondering If i can make something using a arduino to be like a Switch between the Data - and + on the usb? so i can still use one of the computers as the power because the first Pc is always on. So I'm looking for some guidelines on If it would be possible to do something like this . Because there is nothing out there that is only keyboard and mouse kvm. Only thing out there needs a monitor signal to make it work.
No, the Arduino is not an appropriate tool for that, at least without significant additional hardware. It's not a common thing to do.
I would suggest you simply use one of the commercially available KVM switch units - they're cheap now, and will be smaller and more reliable than anything you can build, and you don't have to build them.
If the goal is Arduino control of it, I'd hack up a commercial KVM switch to be controlled by an Arduino
josephchrzempiec:
Because there is nothing out there that is only keyboard and mouse kvm. Only thing out there needs a monitor signal to make it work.
I'm surprised about that. The big problem with KVM units is how they report the monitor ID to the computer; the display resolution tends to get set incorrectly. But the power is derived from the USB connections, not the video so it at least would not be a problem.
Hello all thanks for the reply back. I have a KVM that if i don;t plug in a VGA on the first one it will not let me use the keyboard or mouse. For some odd reason.
Very odd. 
And the reason you are not doing this in software?
Hello Paulcet Thank you for the reply but that will not work sense its yes it will go to 2 computers But i still would need to 2 keyboards and 2 mouses. What i need a way to do 3 computers using only one keyboard and mouse.
I've never seen one like that....
josephchrzempiec:
Hello Paulcet Thank you for the reply but that will not work sense its yes it will go to 2 computers But i still would need to 2 keyboards and 2 mouses. What i need a way to do 3 computers using only one keyboard and mouse.
Click the "4 port" option under model on the page he linked to.
Thank you DrAzzy i didn't see that one 
And then of course, there are the versions of VNC.
Hmmm - there is something funny about this thread. Any time I click on the thread topic (and only this one), Malwarebytes goes off with a message about "Malicious Website Blocked" for something called pulseadnetwork.com Only happens when I click on this thread.
gpsmikey:
Hmmm - there is something funny about this thread. Any time I click on the thread topic (and only this one), Malwarebytes goes off with a message about "Malicious Website Blocked" for something called pulseadnetwork.com Only happens when I click on this thread.
Joseph has a hidden image embedded after his text in post #7.
Joseph, it looks like you've got a virus.
I got a what? a Virus no way. my system i scan daily with my virus scan as well as Spybot and Malwarebytes. Wait how in the heck can you have a image in your text. That makes no sense to me.
Hey Paul thank you for the reply man. I was thinking about VNC but then again i would of need another pc for it. But still up for thoughts.
Holy moly i didn't see it i will scan my system again right now thank you.
I think there are some pretty malicious websites out there that do sneaky things to your computer. There is no telling how you got it.
I did scan my system it found one thing. some adware to a site. i think my brother did it the other day when he was on my pc he was visiting a minecraft game site showing me something. Because I'm normally careful of what sites i go to.
Game sites are notorious for strange things. Malwarebytes on my system was what popped up and alerted me to what was hidden in your post. Stuff happens 