Help with Sun video

[Mr Ian Primus]

--- On Mon, 10/27/08, Steven Hirsch <snhirsch at gmail.com> wrote:

> I'm hoping someone can shed light on this.  For the past
> week, I've been 
> battling to get my Sun Ultra-60 video switchable through a
> Belkin 8-port 
> KVM switch.  The monitor is a Samsung 214T 20" LCD.

<snip>

> What on earth am I missing here?  I don't even see a
> common denominator, 
> but am hoping that someone more familiar with the details
> of Sun video can 
> give me a nudge in the right direction.
> 
> On the subject of the Belkin KVM:  Is it possible that
> their "detection" 
> is simply looking for a grounded pin or a pair of pins
> looped back by 
> virtue of the computer being connected?  Maybe expecting a
> voltage?  If I 
> could trick it into activating the port, I could just feed
> through from 
> the 13W3 adapter and be done with it.  Naturally
> Belkin's site has no 
> information at this low level of detail...

A lot of KVM's I have seen base their detection on receiving power from the keyboard port. This precludes their operation with a Macintosh, SUN, or other machine where you're not switching the keyboard through the KVM. Try connecting the keyboard input to another computer, and then you should be able to select that port.

As for the video itself, most SUN machines use sync-on-green. In this mode, the sync signals are riding on the green video signal. The KVM might not know what to make of this, since it's not going to be getting a sync signal on the appropriate sync pins.

-Ian