[rescue] Sun 13w3 to VGA to HDMI

[Jonathan Patschke]

On Fri, 15 Oct 2021, john ferguson wrote:

> The Sony had BNC connectors on the back and we had a 13w3 to 4 bnc
> connector adpater and I cannot remember ever having any difficulty
> with it.

Some were fine; some weren't.  The SGI-badged one I had only did
sync-on-green.  The Sun-badged one only did composite sync.  I had an
IBM-badged one (P200?) that would go either way, but needed the CSYNC
pin moved.

Of all the schemes, sync-on-green is the one that's easiest to
synthesize from any of the others, so that's the tube that stayed on the
bench.

The limiting factor in having only the 3-5 BNC connectors is that
there's no EDID path back to the framebuffer to negotiate the best
resolution and refresh rate, so the monitor's stuck with whatever the
framebuffer wants to throw at it.  I'd assume your demo setup as
preconfigured to support the monitor it was accompanying.

-- 
Jonathan Patschke
Austin, TX
USA