ADB Switchbox?

[Tempest]

Is there such a thing as an ADB switch box?  I want to use the same mouse and keyboard with my Mac Classic and Color Classic.  If there isn't, can one be made out of an S-Video switchbox somehow?  I wouldn't be switching this while the systems were on, this would be done while they are off.

 

[waynestewart]

I have a KVM switch that switches ADB

 

[Reasons.]

I don't see why an s-video switch wouldn't work, though I'm not an expert. It uses the same connector and my impression is those boxes are all hardware. 

 

[Unknown_K]

Sure they exist, so do serial switch boxes.

 

[Tempest]

I had tried a push button one in the past (an old Pelican brand one IIRC) and it didn't work.  Someone had told me that it was due to something either being grounded or not being grounded (I can't recall which).

Serial switch boxes I can get (there are tons of them in the junk pile at work).  ADB? Not so much.

 

[maceffects]

I have used a S-video one and it worked ok. It was the kind with the knob not push button.

 

[Nathan]

I've heard that disconnecting an ADB device while the computer is on can damage the controller chip due to some kind of issue with the design. I forget where though. Presumably if the switch was designed right it should be safe, but otherwise I wouldn't test it. 

 

[Tempest]

I've heard the same thing.  Like I said though, the computers would be off.  

Maybe the push button type doesn't work then?  I'll keep an eye out for a knob style one (or try a different push button type).

 

[bigmessowires]

ADB devices aren't designed to be hot-plugged or unplugged, but I'm not aware of how it would cause any kind of damage. The issue is that there's some ID assignment negotiation that happens on the ADB bus at startup. If you plug or unplug devices after the computer is already booted, things can get confused, with two devices trying to use the same ID or the computer trying to talk to a device that's no longer present.

 

[Unknown_K]

ADB bus has power going through it, and it is fused (in most cases). Anytime you disconnect and connect to it while on you can have voltage/current spikes.

ADB KVMs probably have buffers to keep things calm when you switch from machine to machine, the cheap switches do not.

 

[Tempest]

I'm not going to switch or plug/unplug anything while the computers are on.  This would only be done when they're off.

 

[olePigeon]

ADB KVMs probably have buffers to keep things calm when you switch from machine to machine, the cheap switches do not.

This.  I've seen first hand a very nice Kensington Turbo Mouse 5.0 get zorked via hot plugging.