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chris
Regular Member

Joined: 24/08/2020
Location: United Kingdom
Posts: 56

Posted: 12:42pm 06 Sep 2020

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Hello,

I just wanted to inform those interested that I purchased two NON POWERED USB switchers, so I could share my PC Keyboard - which is a wired USB keyboard with a backlight - with the CMM2.

(Off topic - but I can also confirm that the wired Logitech K740 keyboard with US layout works fine with full backlight on).

One was compatible, one was incompatible:

DOES NOT WORK: - Sabrent USB 2.0 Sharing Switch for Multiple Computers and Peripherals LED Device Indicators (USB-SW20)

https://www.amazon.co.uk/gp/product/B074TZKGVR

- This device just lit up the CMM2 power light just via the USB A connection, even when the power switch was off. It also didn't work properly. It had a light on the top so it definitely syphons some power and probably has a logic chip inside. I returned this device. Another issue was that the cable management was awful as two cables went in one side, one out the other, it was very scruffy.

WORKS PERFECTLY - EEEKit Bundle for Printer Switch,2 Port USB 2.0 Manual Printer Scanner Sharing Switch Hub 2 PC to 1 Splitter Adapter,2 Pack USB A to B Printer Cable

https://www.amazon.co.uk/gp/product/B07H95P561

Has two physical buttons on the front, and I push 1 to route my keyboard to my main PC, and I push 2 to route the keyboard to the CMM2. It has no status LED and no power is being passed down the USB A.

The unit is very very neat with all 3 cables leading out back so there is no undue cable pressure twisting the device in a diagonal direction, and I'll write more about my desk layout later.

I do advise picking up some shorter USB B to A leads, as the leads that come with this switch are way way too long, especially if your CMM2 is close to a hub on your desk.

I picked up two of these cables, and they seem very high quality.

https://www.amazon.co.uk/gp/product/B07FMT3ZJL

Hope this information helps.

C

RetroJoe

Senior Member

Joined: 06/08/2020
Location: Canada
Posts: 290

Posted: 01:10pm 06 Sep 2020

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Thanks, Chris. I did exactly the same thing and bought the EEKit last week (BTW, in Canada you can buy it without the bundled A-B cables - they are very long, but the unit is intended to share a printer amongst two PCs, presumably some distance away from each other).
Even though it�s a mechanical switch, I find I will occasionally need to reboot the CMM2 after a switch, and/or replug the �common� keyboard. I�m pretty sure this is because the USB chip in the keyboard is getting scrambled by being switched from one host to another, without being �properly initialized. Plus, I have a nice retro IBM keyboard with a PS/2 connector, and am using a PS/2 to USB dongle, which could be compounding the problem.
Net-net though, �mission accomplished� - it works as intended the vast majority of the time. Now I just need to stop reaching for the mouse when I am in �Maximite Mode� :) I must admit, a mouse would be a welcome addition for editing code, but I�m guessing I will rebuild the keyboard-only editing muscles that have atrophied after 30 years of using a GUI!
Edited 2020-09-06 23:11 by jpusztai

Enjoy Every Sandwich / Joe P.

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