feature of the PS2 port?

Why the mouse handling is stop after the ps2 mouse is replugged?

Is it a hw feature or the OS cannot handle?

Not a big problem, but it is not an "Amiga" like method when I have to restart the system after cable rearrangment.

The machine is a micro A1-C.

Bye!

@lazi
Hot plugging of ps/2 devices is very dangerous and you could zap something. Never do that. USB is designed for hot plugging but not ps/2, parallel, serial, etc. so never do that.

That said, there are KVM switches available which can safely switch ps/2 ports because they include proper circuitry to protect the motherboard.

With a KVM (I'm using an active one) I am able to switch between three A1 machines without any issues.

@lazi

My KVM switch have the same problem... keyboard works ok but not the mouse. =(

I always resets the Amiga when changing back from the Windows machine. Its up again after 10 sec so it's not as "bad" as it would be if it behaved the same with the Windows machine! =P

@lazi

As ssolie said never hotplug a ps/2 peripheral. It is not supported by the ps/2 protocol. At best it just won't work after plugging it in at worst it can damage/destroy your computer or the ps/2 port at least anyway.

My first A1200 was destroyed in this way. At first the keyboard just wouldn't work even after turning off/on the computer, next it wouldn't boot at all and a couple of tries later not even the harddrive/cd-rom would start up (apparently the PSU had failed for some reason).

Hmmmm... while this is not directly connected with the problem discussed... I did have a weird problem once with my KVM switch. (I don't have any Amiga hardware connected with my KVM switch, though....)

I had switched to a new dirt-cheap multimedia keyboard from Big Lots... which worked for awhile after the systems were powered on... but then after a few hours, in Windoze XP the mouse started behaving oddly, and so did the keyboard. The scrollwheel on the mouse started causing the browser to behave as if I'd hit the back-button and front-bottom instead... steadily scrolling backward and forward between pages instead of scrolling the page up and down like it was supposed to. And the keyboard switched to all caps on its own, or something of the sort, and I couldn't get it back out, and the KVM stopped responding to the ScrollLock key.

If I powered all the systems off and powered them back on... and then left it a few hours, things went back to misbehaving again as described above.

When I powered everything off and switched back to the previous keyboard, all the problems went away. And when I later switched to a different multimedia keyboard, it also worked fine.

I'm guessing that the cheap keyboard took slightly more juice than was expected, and was drawing down the available power coming through the KVM switch meant for the keyboard and mouse... so that both devices started misbehaving after a few hours.

At that, it might have been a faulty keyboard (I haven't tried it on a KVM-less machine yet...)

Just something to bear in mind...!

@all

I know that there is +5v on that conector, but I think that if the plug is in the good position there should be no problem to hotplug.
However I will not do it again! Thanks for the tip.

Bye!

@lazi

Regardless of the risk of electrical damage, the PS/2 protocol depends on polls and replies in a continuous stream, and there is no provision for recovery from lost polls.

So if you unplug the device, the software in the PC won't know what to do, and when you plug in a new device (or even the same one), there is no guarantee that the two "ends" will be able to start talking again. You need hardware on the motherboard to signal the software that the device has been disconnected, then reconnected, and software to recover from it. None of these features is listed or demanded by the PS/2 spec, and makers don't include stuff that they don't have to.

@tonyw

Quote:

I did not know that the PS/2 implementation of input ports are so limited.

I think nobody will miss them from the next Amigas (e.g. SAM440ep).

On the electrical side of things, it should be easy to design a hot-pluggable peripheral by simply building out the ground connectors further than the other connectors, so that the device gets connected to ground first before anything else gets connected. I believe this is at least similar to how USB hot-pluggability works (any correction would be welcome). The real problem is the software to handle the event. You would need to watch the voltage on the connectors to alert the subsystem when a connection/disconnection event occurs, so that it could properly respond.