First, If you open some OLDER KVM switches you will find out that they
have JUST wires in them.  These kind are not good for anything more
then a paper weight.  The ones that work are the ones that simulate a
keyboard, and mouse on the ports that AREN'T viewed at that second
(Meaning when you switch from "A" to "B" the computer on "A" still sees
a keyboard.) Second, If you want to use the older switches you need to
switch to the machine you want to use THEN tap your Num Lock TWICE
(Ignore the lights they will NOT blink correctly) Doing this does TWO
things:   1.) This RESETS the cirucits in the keyboard for the new
machine. (AND MUST BE DONE or you WILL get RANDOM charecters)   2.)
Resets Num Lock, Caps Lock, and Scroll Lock to their orignal settings
AND their lights to their orignal settings (For that Machine)

Third, the DreamCast might not be able to deal with hotswaping the
keyboard which would mean you need one of the switches that simulate a
keyboard and mouse on the inactive ports.

IN>When I tried that with my 2-port KVM, even if I never switched sides PSO wo
IN>be freaky.. hooking the keyb > adapter > DC straight worked fine, but the K
IN>made it freak. keys wouldn't work or stick or spit out random stuff.
IN>
IN>The KVM works fine on PCs tho 
IN>
IN>-JV
IN>-----------------------------------------------------
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