Bless me STW, for I have sinned. It has been several weeks since my last (explicit) confession of ignorance

I’m desk-sharing with a colleague (we work opposing halves of the week). I have a desktop PC and he uses a laptop with a dock. His dock needs my mouse & keyboard USBs plugged into the back of it and I’m told that this should also allow them to work my PC but they don’t and I have to re-plumb every week

There seem to be splitter leads but I don’t really think that they’d allow me to do what I want, which is to have the mouse & keyboard leads running into his dock and my PC all of the time, allowing input into either (they’ll never both be switched on at once).

Advice pls, preferably in short-syllabled noob terminmology

What you are referring to is a KVM switch

I’m told that this should also allow them to work my PC

Who told you this? Can’t they help.

Just plug all the peripherals and monitor into the dock then either manually plug the dock into whichever machine is being used, or buy a cheap USB switch and use that to select which machine you want to use.

If you’re already doing this, then you probably need to install the drivers for the dock.

Simple answer: tell him to get his own damn keyboard and mouse!
Probably a cheaper solution than most KVM switches too.

Also a lot less germy.

Simple answer: tell him to get his own damn keyboard and mouse!

This. You can buy a wireless keyboard and mouse set for ten quid, and a decent one for £20. What are you fannying about with switches for?

What you are referring to is a KVM switch

If you must share peripherals, this is the correct answer. A KVM takes a Keyboard, Video display and Mouse, and shares it between two (or many more) PCs so you can switch between them.

https://www.amazon.co.uk/Belkin-OmniView-Switch-Port-Remote/dp/B000FBXV3C

plug the dock into whichever machine is being used

I don’t think a “dock” in this context means what you think it means. Or at least, it certainly doesn’t mean what one of us thinks it means. A docking station is usually a base that you plonk your laptop into, it’s specific to that particular model of laptop.

I think splitter leads would actually work in this scenario (when both devices won’t be powered on at the same time). A KVM is more so you can switch quickly between two PCs and only have the mouse/keyboard input go to the one you’ve switched to. With splitter leads the mouse/keyboard input will go to both devices all the time but if one is switched off that shouldn’t matter. I’ve never tried this myself though…

As Cougar says, is this a “dock” which the laptop clips into, or a “port replicator” attached by USB cable. If the latter it could probably be used with a PC in the same way the laptop is. Otherwise a KVM.

sorry all – work got in the way for a bit there

Yeh, “dock” is a specific interface for connecting an acer laptop and has a series of USB, hdmi, vga ports in the back (It’s also “powered”, presumably just to pass through to the laptop)

I did wonder if separate keyboards might be easiest, but the desk’s not massive and anyone who’s seen a photo of my garage will know that I detest clutter 😉

Ooooh, if the screens work OK already, is this enough ??

Who told you this? Can’t they help.

Course not – I’m the IT expert round here 😳

..allows one button swapping between 2 computers to share 4 USB 2.0 peripheral devices without constantly swapping cables… ideal for sharing devices such as printer, scanner, mouse, keyboard..

Sounds rather like it yeah. 😀

it’s specific to that particular model of laptop.

The three docks I have use USB, so they are universal. Even if you have a proprietary dock for the laptop, you should still be able to just use a cheap USB switch to select which machine is connected to the keyboard and mouse (which you can plug into a cheap hub so they run off a single USB cable.

Ooooh, if the screens work OK already, is this enough ??

What do you mean by “if the screens work”? Have you got a screen each? Or does your colleague not use the monitor at all?

With splitter leads the mouse/keyboard input will go to both devices all the time but if one is switched off that shouldn’t matter. I’ve never tried this myself though…

That’s not a USB splitter though, what you appear to be describing is a hypothetical USB combiner. I can’t begin to imagine what would happen if you tried to plug one USB peripheral into two hosts simultaneously, it’d probably open a wormhole into another universe.

What do you mean by “if the screens work”? Have you got a screen each? Or does your colleague not use the monitor at all?

2 screens, each with 2 leads attached, one from him and one from me 😯

I can’t begin to imagine what would happen if you tried to plug one USB peripheral into two hosts simultaneously, it’d probably open a wormhole into another universe

that is exactly what I wanted before I saw those various switches but still only one of the PCs will be in use at any time. Surely the fabric of space/time is up to that ?

edit: Splitter/combiner – are USB leads directional? CpnFlash will be pleased

still only one of the PCs will be in use at any time

But if it was just a normal lead that split into two then even if the other PC was off but still attached then it would receive 5 volts from the one that was on.

Which may or may not end well depending on what protection they’ve put on the USB port (this sort of thing has killed Macs before)

. I can’t begin to imagine what would happen if you tried to plug one USB peripheral into two hosts simultaneously, it’d probably open a wormhole into another universe.

That could be awkward.

You’d try to fly through it but would then have to reverse and try it again upside down

Which may or may not end well depending on what protection they’ve put on the USB port (this sort of thing has killed Macs before)

Ah, yeah I can see that might be bad. Something tells me our kit isn’t top line generally.

To Amazon, comrades !!

edit: Splitter/combiner – are USB leads directional? CpnFlash will be pleased

The short answer is “yes.”

Technically the leads aren’t “directional” as such. USB is a client/server architecture – ie, one end tells the other end what to do. USB-A ports – the ports found in a PC – are used on host devices. USB-B (square-ish connector common on printers), mini- and micro-USB will all be found on client devices.

This is why you’ll never* see a USB cable with the same plug at both ends because the two different kinds of devices use different connectors.

When you get a splitter, you’re taking one USB-A port and turning it into two. You cannot meaningfully “split” a single client device across two hosts – how would they know which was in charge? You’d effectively be trying to turn two A ports into one (hence my ‘combiner’ comment). There are actually cables which do this, but the second port is used solely for adding additional power and doesn’t transmit data.

(Note to geeks: I know I’ve oversimplified this.)

* – for all practical purposes anyway. You can buy gender-benders and the like but usually if you’re going to change the gender of a connector then you first need a positive answer to the question “do I know WTF I’m doing?”

You cannot meaningfully “split” a single client device across two hosts – how would they know which was in charge?

I think the OPs scenario would be that only one host would actually be powered on.

So in principal you could devise such a cable, with the addition of some protection diodes to make sure that the other host doesn’t get zapped with 5 volt input.

In theory it could even handle both hosts being on by adding some circuity to always prefer one host over the other.

But that’s all very niche and the little switchable USB hub he linked to probably does a fine job with less user confusion.

I think the OPs scenario would be that only one client would actually be powered on.

Until that one time when someone forgets. (-:

How about just putting a small USB hub at the front of your computer so disconnecting and reconnecting the USB keyboard and mouse is as easy possible. It sounds like you only need to do this once a week so just not having to go crawling round the back of the desk might be enough to ease the frustration?

But that’s all very niche and the little switchable USB hub he linked to probably does a fine job with less user confusion.

That’s a good point, if the other user isn’t onboard with this you will still come back to your desk to find the keyboard and mouse disconnected from the KVM 😀

This is why you’ll never* see a USB cable with the same plug at both ends because the two different kinds of devices use different connectors.

We have Lenovo port replicators which connect to the laptop using a double ended USB-C cable.