Does level1tech KVM support switching from the computer?

Level1 Store KVM Helpdesk
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My monitor does not support switching inputs over DDC/CI. Does the Level1techs KVM support something similar? Eg. just from a Linux command terminal allowing switching of inputs? And then, if I connect to Input 2, does it still allowing switching from the USB of Input 1? (eg. 1 host is always in control of input switching)

Also, how fast do they switch in practice? My monitor is really really slow when switching inputs (like 5 seconds or more, besides having to use the horrible slow on-screen display). The Level1Techs KVM do not support EDID emulation, so doesn’t that make them really slow also (OS be like: Hey, new monitor detected, 10 seconds later → finally a picture). I cannot bear if switching would take like more than 2 seconds.

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My experience is with the 4PC 2Monitor HDMI 2.1 KVM.

There is no way to instruct the KVM to switch from the connected PCs themselves - it doesn’t appear as an addressable USB device as far as I know.

There are several options to switch:

  1. Front-panel buttons on the KVM
  2. Hotkey key sequence from the keyboard
  3. Dedicated USB numpad connected to the keypad port
  4. Serial/RS232 control

The front-panel option works 100% reliably every time, and no unusual quirks to note.

The hotkey key sequence may or may not work depending on factors such as how NKRO is implemented on your keyboard. For me, it works fine with a Cherry G80-3000 (basic standard USB HID) but doesn’t work with my Varmilo keyboard due to how they implemented NKRO.

The dedicated USB numpad input allows direct switching using e.g. numpad 1, numpad 2 keys. You can also use something like a small 3/6/9 key macropad supporting QMK/VIA from somewhere like AliExpress programmed to behave like a keypad if you don’t want a full numeric keypad.

The Serial/RS232 control is very handy if you don’t mind building something with a microcontroller like an ESP32 or a SBC like a Raspberry Pi. For example, you could set up a basic web server to issue serial commands from a web browser, a set of physical buttons wired into GPIO pins, or if using a Raspberry Pi or other device with its own USB host, a script to receive USB keyboard and issue serial commands to the KVM.

Having said all that about the standard methods, the RS232 switching would probably achieve what you want to do - plug a USB RS232 adapter into the PC on Input 1, and you could just issue serial commands from that one PC.

Both the hotkey and numpad inputs have a slight annoyance where: consider you might be switching from PC 1 to PC 2. You put PC 1 to sleep manually and then enter the hotkey for PC 2. This immediately wakes PC 1 for me 95% of the time. The front-panel switching doesn’t suffer this, and I’m currently testing the RS232 control which I believe should also be fine.

The HDMI 2.1 KVMs from Level1Techs shouldn’t have issues with EDID, my understanding is only the DisplayPort KVMs lack this. For me, switching takes around 2 seconds for video to appear. USB switching takes a bit longer - typically 5 to 10 seconds. Both these are definitely slower than an TESmart KVM (the 4 PC 2 Monitor USB 3.0 4K60 model) I briefly tried before getting the L1Techs KVM. The TESmart KVM switches both video and USB pretty much instantly, but ultimately had to send the TESmart back because of lots of USB reliability issues.

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