OT: Smart USB to PS/2 keyboard adaptors

That's the "wrong" way for most adapters ... maybe use an ancient KVM switch?

I think you may be unlucky. I'd like the same to allow me to use a modern cordless mouse with PS2. I do have an older USB keyboard and mouse that work with PS2 via a simple adaptor - but they're getting rather worn.

Yup, you need protocol conversion.

For the price I would hope this one would

Owain

Aha, yes I had forgotten about blackbox - that may well do the job (and the price, while a tad steep, is still significantly less than replacing a dual head four way hi res KVM)

Its the ancient KVM switch that forces the requirement - its PS/2 only.

Sort of same here. My KVM switch is DVI and PS2. And one of the computers is the old Acorn, with no USB at all. Even although it has been modified to a digital video card.

If you buy that convertor let us know if it does what it says. I'd happily pay that to be able to use a current USB cordless mouse. The old one I'm using is very power hungry.

I remember there was a project to emulate a PS/2 keyboard with an Arduino ...

Ah,

I'd recommend a new KVM - specifically one of the units by Aten. They seem excellent - I have 2, 4 and 8 port versions here and have never had the problems I encountered with other makes - particularly Belkin!

You can get various types and cables, and they even have a facility for firmware upgrade.

The one I have seems ok generally (although its XVGA rather than DVI/HDMI) works well and decent quality. The only minor gripe I have with it is that the hot key for switching is not reprogrammable.

It seems a bit excessive binning a working solution for the want of a USB to PS/2 adaptor.

The Aten ones do look quite decent though. I susspect I would need something like the CS1644A:

And I've had actual firmware upgrades that fix actual problems.

I've got loads of these things in a box, surplus from upgrades:

As they the "dump adaptor" you refered to, and why are they not suitable?

The OP says they presuppose that the keyboard/mouse are designed to be used with PS/2.

(I wonder whether the keyboard/mouse variants are the same electrically?)

And another +1 for Aten KVMs. I had the 2 way (CS62U, VGA / USB / Audio) on here for years and recently replaced it with their 4 way with similar functions. They are the button less / keyboard only type:

As they take up less (no) room on the desk. ;-)

I have firmware upgraded both the ones I bought new and one of the ones I bought second hand (the other doesn't want to play). Also one of the second hand ones seems to be missing a colour on Port 1 (but otherwise works fine) so I might take that to bits and see if it's a cable or something electronic (they were both cheap enough).

The 4 way is slightly more clumsy in use as you have to hit (from default) Scroll Lock > Scroll Lock, [port number 1-4] > Enter or Sl, Sl, Enter to cycle though them one at a time. Or you can have it scan though tem at a preset time interval and it defaults to the one you first turn on (which is handy if you just grabbed one at random and plugged it in). ;-)

The only time the use of a KVM switch (and it could have been any make or model) was an issue is when effectively removing an re-plugging a USB mouse caused Linux to 'forget' a mouse slowing command (so no use even if it was actioned at boot), until I found someone with sufficient programming skills willing to help and made the 'fix' work automatically using udev or summat. eg. When that USB device (ID) appears, action this setting.

A mate had three 'other' brand (and not cheap either, cira 80 quid) 4 port manual, VGA KVM switches fail on him over time. Upon my recommendation he replaced it with the Aten equivalent and it has been solid since.

I sourced another mate a cheapo push button 2 way KVM (eBay) and that's also been fine for a couple of years now (touching wood). ;-)

They are now one of those things I couldn't be without and are far superior (for my usage / purposes) to any 'soft' keyboard switching (as I might want to be able to do stuff in the BIOS etc).

Cheers, T i m

Aten won't say that their KVMs support use of USB dongles for wireless mice, but I find in practice that the Logitech unifying receiver works plugged direct into a KVM USB port for all standard functions.

But if you use any "clever" options in the Logitech configuration app then, fairly understandably, those settings are reset whenever you change ports.

IIRC, modern USB mice and keyboards (or perhaps only mice) use a different protocol to older ones.

I have an old USB mouse that works just fine using a basic USB to PS2 adaptor. A new USB mouse doesn't work. Both using the same KVM switch.

I think it's that USB mice/keyboards which are supplied with the green/purple adapters can sense (by a loopback pin?) whether the user has connected the passive adapter, and the device falls back to sending PS/2 signals rather than USB signals.

My Aten DVI/PS2 KVM works perfectly with an old USB cordless mouse (Technike) dongle and simple adpator. But doesn't work with a new USB mouse and dongle.

Ah. So would one of those convertors shown earlier get round this? If so, would be well worth the money. My current old mouse is getting pretty tired, and is much harder on batteries than the modern one I use on another machine.

Oh, I thought I read somewhere (on their own blurb) that it typically will, as long as it's plugged into the KVM directly (so presumably, not via a USB hub etc)?

Ah: "Supports multifunction and wireless keyboards and mice NEW!"

Same here with other brands.

Not tried that myself but it makes sense.

Cheers, T i m