KVM (or USB switch) Suggestion

Any suggestion for a 3 way K(V)M switch? I do not care about video, actually. I think @kas1e has done this sort of thing before and I think for the AmigaOne machine a powered KVM is the better solution?

@rjd324

TESmart is the make he recommended but can't remember which model.

Cheers

@rjd324
I use an ATEN CS1784A, but I chose that primarily to get the video switching with DVI-I support so it could switch both scan-doubled classics, CyberVision64 output and NG Amigas

Thanks so far.

It would be important that it also doesn't have any weirdness during the bootup menu, if I ever need to get into that.

The ones I tried:

- StarTech.com SV431DVIUDDM (does not work in CFE AmigaOne-X1000, CFE hangs when the computer is switched on and the KVM is connected to the keyboard port. If AmigaOS had somehow been booted, then CFE won't freeze after a warm-reset), so you need to plug the keyboard to the 1st USB port or use a second keyboard if you need to do something in CFE.

- StarTech.com SV431DPUA has audio switching too. Needs DVI / HDMI to DP adapter but works really well and supports 2560 x 1600 @ 60Hz. This version is discontinued, there is a version SV431DPUAv2, never had a chance to try it. Works on CFE for most part, but sometimes a reset is needed.

- ATEN CS692, is only 2 port switch, but works without problems on CFE

- ATEN CS22U only 2 port switch, but works on CFE

I would like to know if the tesmart works with CFE, they are on sale right now, DKS402-P23-EUBK would be my kind of thing.

@Tuvok

Got an ATen CubiC CS1794 here for my Win10, RasPI2 and another small thingy. Supports 1920 x 1080. Accomodates 4 computers. Flawless.

Got another ATen CS1844 here for a whole slew of beefier RasPi's: it supports 2 times 3840 x 2160 monitor, 4 computers, flawless.

No Amiga hooked up to a KVM, as I like to work on a 1920 x 1200 screen and don't know if and how the KVM handles that.

ATen is an expensive premium KVM, but I think it's worth the money.

OldFart

@OldFart

How would you feel about actually testing it out? Do you have an X5 and an X1? Uboot/CFE would be interesting.

@OldFart

Thank you for the suggestion.
I'm waiting for the BlackFriday deals to order both the Tesmart DKS402-P23 and an Aten CS1924M, I'm looking forward to test them. Unfortunately the latter one is a bit more expensive as the tesmart, but does have a little less functionality.
Let's see which one works best.

@graff
@OldFart

Hi, I acquired an Aten CS1784A, I installed the latest firmware from the Aten website (version v1.2.111 2025-03-11) the firmware which came with the KVM would not recognise my keyboard, after the update the keyboard works.

Anyway, sadly the X1000 refuses to boot if the KVM is connected to the "keyboard-usb-port".
It waits at the X1000-boot picture forever.

I could use a different USB port, and connect a second keyboard to the Keyboard-USB port to be able to use the CFE-boot menu, or the AmigaBoot menu, but then why use a KVM if I need a second keyboard anyway.

I did notice that if I disconnect the KVM, boot AmigaOS 4, connect the KVM again, then the KVM can be used in CFE too even after a reset using the button on the case.

Maybe there is a CFE variable or command that could be set in the startup variable to make CFE do whatever OS4 does? Something is being written to some register maybe?

what does the "set HID" command do in CFE? Does anybody know?

I know the CFE sources are lost (or something like that) but maybe it is possible to fix this with some trickery?

@Tuvok

Have you tried connecting your keyboard to a USB hub that is plugged into your KVM switch?

Cheers

@Tuvok

I use a CS1784A with some of my machines also, including an X1000.

I have found that it works best if I connect the keyboard not to the socket with a keyboard symbol, but to the "generic" USB socket below that on the back of the KVM switch. I have the mouse receiver for my wireless mouse (Logitech) in the keyboard socket. And I don't know if it matters, but I currently have the X1000 connected to the 4th section of sockets.

Also, I have found that you have to experiment a bit to find the best way of pressing the switching buttons to make sure the USB is also switched; my technique at present is a short press on the middle of the button (on the little groove).

Best regards,

Niels

@Tuvok
I don't have an X1000 myself, only MicroA1, SAM460 and X5020, so can't comment on how CFE uses USB keyboards. Does it stall forever in CFE? What if you switch the KVM away from the Amiga and back? Or presses keys on the keyboard?

I've never upgraded the firmware of my CS1784A, so I guess mine is still running some ancient version :)

@nbache
I always uses the keyboard shortcut for switching the KVM, but that probably requires you to use the keyboard USB port for it to work.

Regards,
Thomas

@graff

And I never thought about upgrading the firmware of the KVM switch, should probably try that some day when I feel lucky .

Maybe the newer firmware would even let me put my keyboard back where it was meant to connect? You never know (unless you try).

Best regards,

Niels

@TiredOfLife

Quote:

I tried after reading your comment. Hower it does not help. In the manual of the KVM the manufacturer says no hub should be connected to the dedicated keyboard port.

Also, now that I tried ,I can confirm the explanation in the user manual that the keyboard-switching shortcut does not work with an USB hub in-between.

it was worth a try, thanks for your suggestion.

@OldFart
@nbache

I tried my luck with the ones you mentioned, but CFE does not want them.

Unless I connect the KVM to a different USB port, the amiga will not boot.

I read the error code in the Serial-output but can't remember the exact wording now.
It seemed like there also was some typo in the error message. When I saw the error message I had the feeling that there is maybe some simple error in the CFE source code. Some forgotten quotation mark, an extra CR, something small like this.

The funny thing is, once AmigaOS 4 has booted once, then CFE will not stop the booting process in subsequent hard-resets.
To clarify:

Test 1:
- connect KVM to the keyboard USB-port of the X1000
- turn on X1000
-> Boot process halts, nothing will move the X1000 to boot. No resets using the computer case reset-button will help. Only disconnecting the KVM from the port persuades the X1000 to boot.

Test 2:
- connect the KVM to any other USB-port of the X1000
- turn on X1000
-> boots to AmigaOS4
- connect KVM to the Keyboard USB-port of the X1000
- use your favourite method to "hard-reset" (e.g. Workbench->Shutdown->Restart Computer)
-> Keyboard is available in CFE to select menu entries or typing
-> X1000 boots to AmigaOS after menu-timeout

This can be reproduced every time.

So my conclusion is that AmigaOS4 must do something to the CFE USB stack.
It writes to some register, don't know.

I wonder if it would be possible to set a CFE-env-variable that does whatever Voodoo AmigaOS4 is doing.

There is a "Set hid max" variable to be set in CFE, I played around with it, but to no avail.

@nbache

Be aware of some changes in the way your KVM operates If you update the firmware of your ATEN. In some models they have changed the behaviour of the front panel buttons:


https://www.aten.com/nl/nl/products/re ... te&type=firmware&eid=2574

Quote:

at the time of writing the latest firmware for our cs1784a is v1.2.111 (2025-03-11).
Said FW did improve the compatibility with my mechanical keyboard.

@Tuvok

Thanks for the heads-up.

I think maybe my firmware is already 1.0.077 or more, because the buttons seem to already function like that for me. Now that you mention it, I remember reading something about it before.

At some point when I get time, I will try checking my KVM switch's firmware version and also update it to the latest firmware, but that will probably not be until some time in the new year.

As for why it works so strangely on your X1000, I don't know. I don't see such behaviour on mine. But I'm no "Voodoo master" .

Best regards,

Niels

If you don't need video, a simple USB switch should work fine.

As a bonus, you can mount USB memory stick to share files between attached computers. Or Printer or whatever USB-device you like.

Been using similar device for years:
https://www.aliexpress.com/item/1005004198593961.html

A usb switch would work fine for me, so long as it it works with CFE/UBOOT.