[uunix]

I notice on many video input cards, like my own Digital Video board, there is an undocumented (as far as I know) BNC input labelled 'TRIG'

It's never mentioned in any docs.. anyone know what it is?

Oh I say 'any docs' what I mean is the docs I've read for installing etc.

[bjames]

GPI trigger.  Not sure what it means, but as I am shopping for Digital DVCAM edit decks, I noticed that these use trigger to insert markers (up or down).. again im still learning what all this means.  I aslo noticed in the Jaleo 3.5 for Octane Software Installation software, it shows you have to configure the GPI (trigger) thingy.   The Jaloe documentation is installed when you install Jaleo.

I have a Digital Video board for the octane coming in soon.  So I will be trying to figure out the cabling.

FWIW..  So far my sights are on the Sony DSR-1800 DVCAM editing deck that has the full SDI options installed.  This unit was introduced in 1999/2000 to be Sony's answer to Digital Editing for Professional video.  The Deck is fully compatible with SMPTE 259m standard (what the digital video option uses).   

When the DIVO option was introduced, SGI was kind of ahead of the curve in terms of what was being used in the industry.  If you noticed in the DIVO documentation, it shows the use of analog -> digital and digital-> analog converters between the camera/deck and SGI.  The reason was there weren't any decks that were full digital SDI yet... unitll the Sony DSR-2000 was introduced in 1999 that included SDI connections.  The DSR1800 is slightly newer than the flagship DSR2000 but has improvements over the dsr2000 here and there.

During my research, I found that in order to get full compatibility, you have to be careful what you interface with  i.e. there are many standards of SDI now 1G, 3G, 12G that comply to different SMPT standards.  I would guess that mating the wrong SDI will not work.  So look for hardware from around 1997-2005