Custom External Switch for L1 KVM

I recently purchased one of the L1 KVM switches. I have a logitech G510 keyboard which has additional buttons for macros and media controls. When I connect it to the kvm via the HID ports, the extra buttons don’t work so I have it connected through one of the USB 3 ports. I also have the kvm switch mounted under my desk, so I needed a solution to be able to switch inputs easily.

I found a 2-key keyboard that you can customize to be any key/key combination, so I programmed it to be scroll lock, scroll lock, 1 and scroll lock, scroll lock, 2. Now the 2-key keyboard can sit on my desk and act as an external switch for changing the kvm inputs.

Here are the links if anyone else is interested:
Amazon:

AliExpress:

Software:

5 Likes

does this definitely work? i tried another brand of keypad (designed to play osu), but it didn’t have the ability to configure it for 3 key strokes…(it uses software from sayobot - and hoping it isn’t all an elaborate rubber ducky!)

this is the one i bought

for reference this is the one I bought, which neither has macro functionality, nor does it even seem to work, If i set 1, 2, 3, 4 and Scroll Lock as they keys and try and trigger it manually - (they keys come through to the connected PC fine - i can see in Excel), but the kvm does not trigger a change in port.

This is why I custom built a keyboard and put QMK on it. That way I can build all the keycodes in firmware and they pass the HID inputs on my KVM. Same with keycodes that activate macro’s.

I use the falcon rgb8 as well as custom teensy. Both of those well fine

It definitely worked for me. The key is to make sure the keypad imitates a HID device after programming the firmware. I also had to play around with the delay between the key presses. I think 0.2 seconds worked well.

@jelloman: I bought this same 2-key keypad for my L1T KVM. What exactly do you have to do to “make sure the keypad imitates a HID device after programming the firmware”?

I have the same question, the one I bought doesn’t work, Ecarke 5 Keys Mini Macro Mechanical Keyboard

@wendell: Any thoughts on this?

I tried another two-key keypad off Amazon (this one), and still no love from my KVM. Reeeeeaaally feel like I’m missing something, here…

1 Like

Having the same issue. Can’t get any of the key commands to work. Using a GMMK Pro, I mapped two keys to scroll lock and num lock respectively and the KVM doesn’t seem to pick it up.

Far as the gmmk goes, Disable nkey rollover

…what about the Ecarke 2-key keypad that kicked off this thread? My little keypad is sitting here very lonely and unused. Any thoughts on what it is @jelloman was doing right and I’m doing wrong?

Delay between key ‘presses’?

1 Like

I used the delay between key presses that @jelloman mentioned… no luck.

That same model should behave as a HID device by default. The one I received was programmed to be the “1” and “2” keys initially. I had to use the provided software to reprogram the unit to have the keys run a macro to do the key presses to switch the kvm input (scroll lock, scroll lock, 1 or 2). You can use a keyboard tester to validate the re-program worked correctly. Then make sure you plug to macro keyboard into one of the HID ports on the kvm.

I think the problem may lay with the Logitech keyboard, I only say this as I am running a HyperX Alloy Elite RGB and everything just works, multimedia controls, volume control and the controllable per key RGB lighting.
In saying that tho I only use the button on the front of the switch to switch between my PC’s and my setup transfers a hell of a lot between the two. Hanging off my 2 PC 3 Monitor KVM I have A my Alloy Elite, Razer Death Adder V2 and an ACASIS powered 16 Port USB 3.0 hub with an upgraded power supply capable of delivering 5v @ 3a per port.
I run mechanical and solid state hard drives off of it and they happily switch between my two PC’s ( just don’t do it while you are doing file transfers between drives )
If the KVM’s can handle all of that I would say the keyboard probably is the issue.

That same model should behave as a HID device by default. The one I received was programmed to be the “1” and “2” keys initially. I had to use the provided software to reprogram the unit to have the keys run a macro to do the key presses to switch the kvm input (scroll lock, scroll lock, 1 or 2). You can use a keyboard tester to validate the re-program worked correctly. Then make sure you plug to macro keyboard into one of the HID ports on the kvm.

Definitely did all that. And it will not switch my 10gbps 2computer/3monitor L1T KVM.

I also bought the 4-key keypad confirmed to work in this post – and I’ve had absolutely no luck with it, either. (I can’t get the keys to input anything at all when the keypad is plugged into a HID port, let alone switch my KVM.) I’m really confused why everyone seems to have no problem with these keypads, but my KVM apparently doesn’t recognize them as a HID device.

Have you unplugged the kvm for a solid minute? There’s an overcurrent protection built in that has a long timeout before re-enabling power.

1 Like

I just tried that, and it made no difference, unfortunately.