Paul G. Allen wrote: > I've had this strange problem with two different KVMs and two different > sets of cables. By different I mean different mfg. and different type > (one a 2-port with built-in cables, one a 4 port with third party cables). > > My laptop(*NOT* a name brand, no docking station) has a PS/2 port on it > for either a mouse or keyboard. I use a cordless USB mouse, so I use the > PS/2 port for an external kybd. I have a small, portable kybd that works > fine when plugged in at any time on the laptop. When I plug in the cable > from the KVM , sometimes the kybd connected to the KVM works on the > laptop, sometimes it doesn't (Note: The kybd connected to the KVM is one > of the older, bullet-proof IBM models with the really loud clicking > keys). It seems to be a crap shoot. The other interesting thing is the > kybd always works on the desktop, no matter which KVM I use. > > Anyone experienced this with a laptop? Anyone know of a solution? (maybe > I need to have the company buy a certain brand of KVM or kybd?)
I'm remembering a problem with older KVMs and older keyboards having problems because the keyboard power was not maintained during a switch. Hmmm, it may actually have been a homemade switch. If your kbd - KVM - computer works on boot, but then fails by switching away and back, that would probably be cause for suspicion. I guess another test for susceptibility would be just to unplug/replug your live kbd, and see if it stops working. A fix I've seen work is to connect all computer power pins to the KVM keyboard-cpu connector thru diodes to the power pin on the keyboard-device connector. That way, as long as _any_ computer is on, the keyboard has power. Now, I haven't actually done this myself, but that's what was reported to me a few years ago and it sounds reasonable. I had assumed that the problem was not more common because: a) not all keyboards are susceptible b) KVM design has evolved to avoid the problem (possibly with the same kind of fix) [or possibly] c) nobody in their right mind builds their own KVM switches Regards, ..jim -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
