An effective way to switch host computer

Learning and discussion
1

Hello!
I often use my keyboard with a desktop PC but sometimes I also need to (concurrently) work with a laptop and unplug / plug my keyboard every time I need to switch device is a hassle. (I don’t wanna use laptop keyboard.)

so I’m thinking about how to switch between usb-wired devices. is it enough to just switch D+ and D- ?
like this:

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imagine I have a keyboard with 2 usb ports, 1 plugged to PC and another to laptop
then if I want to switch between PC and Laptop, I just flip the toggle switch.

I’m not sure if it’s alright to connect vcc,gnd from both hosts.

what is your thoughts about this?

btw, I do know about KVM switch

2 Likes
2

There are software solutions to this, given that you have networking between the machines.

I use Mouse without Borders a lot at home, but that only works between Windows machines. Synergy works between all OS’es.

3 Likes
3

There are also switching USB hubs instead of full blown KVM switches. Like this https://www.amazon.ca/UGREEN-Computers-Peripheral-Switcher-One-Button/dp/B01N6GD9JO/

As for the technical answer you are looking for I cant help sadly.

1 Like
4

I just bought exactly that UGREEN switch and it works perfectly without external power even with a Tada68, Logitech Unified dongle and Wacom tablet plugged in.

I use it to switch my HID between 2 KVMs :wink:

5

Don’t risk the DPDT switch idea. You could easily damage one or other host if there’s a difference in ground potential. Get the UGreen USB switch mentioned below.

https://www.cablinginstall.com/cable/article/16465312/ground-potentials-and-damage-to-lan-equipment

2 Likes
6

I use Multiplicity. Paid, but I never have problems with it, and it also has KVM capabilities.

7

oh my lord :scream: … I guess I have to scrap this idea :frowning_face:

8

I use the USB switch below for what seems to be the same purpose and it works fine. No need to reinvent the wheel.