Friday, March 25, 2011

Adding a PS/2 Port

I had always used PS/2 rather than USB mice and keyboards.  USB had the drawback of not being functional in some circumstances (e.g., when I was booting from some kinds of CDs, or was adjusting the BIOS settings before the operating system loaded).  This seemed to be true even when USB devices were enabled in BIOS.  Unfortunately, my new motherboard had only one PS/2 port.  I would now have to go with at least one USB device.  Between the two, USB mice seemed to function better than USB keyboards in the environments just mentioned, so I could live with a PS/2 keyboard and a USB mouse.

Problem:  I had two computers, and was using a keyboard-video-mouse (KVM) switch to share my mouse, keyboard, and monitor between the two computers.  Now I needed two PS/2 connectors unless I wanted to get a USB KVM, mouse, and keyboard.  I didn't want to spend the money, and I liked the PS/2 KVM better than what I was seeing in the USB KVMs.  So there was a question:  could I add a second PS/2 port to a computer with just one PS/2 port?

I tried using Y-splitter cables, which were physically able to connect two PS/2 devices to one PS/2 port.  But they didn't work:  only one device or the other (i.e., mouse or keyboard) would operate.  I ran a search and saw some references to adapters that would convert the computer's serial port to PS/2, though apparently that could have its complications.  The pictures looked familiar.  I dug around and found that I already had something like that.  I didn't want to reboot the computer right then to try it out, so I searched a bit more.  There seemed to be some USB to PS/2 adapters; presumably those wouldn't have the serial port problems.  I also found a PS/2 adapter backplate, which would have required an unused PS/2 header on the motherboard.  I wasn't sure if my mobo had one of those, but I could scope it out when I did shut down.

I wasn't sure which of these solutions I would ultimately wind up using, or even if I would definitely try to stick with PS/2 rather than USB.  This is as far as I took the question at this moment.



Glad to see this post is fairly recent. Maybe I still have a chance of getting a reply.

I have the exact same problem. A PS2 KVM switch and only one PS2 port. I tried a 2 PS2 to USB adapter but it works awfully. The keyboard behaves strangely and the mouse doesn't work at all. What did you go for in the end?


I've got the keyboard connected to both machines via PS/2, and separate USB mice, one on the left hand for the machine that sits over there; the other on the right side for the machine on the right. Both are set up as right-hand mice (i.e., left-click does the same thing on both). I have two monitors -- one for each machine. I have mostly trained myself to shift hand positions as soon as I shift eyes to the other monitor. That is, I rarely (but still sometimes) delete something on screen A when I meant to be deleting something else on screen B. It's a little bizarre, but it has its advantages.